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subject, Ich, is in the nominative case, the direct object, das Buch, is in the accusative case, and zum Verleger is in the dative case, since zu always requires the dative (zum is a contraction of zu + dem). However: Ich habe das Buch an meinen Freund (accusative) weitergegeben. 'I forwarded the book to my friend.' (weitergeben = lit.: to give further). In this sentence, Freund is the indirect object, but, because it follows an (direction), the accusative is required, not the dative. All of the articles change in the dative case. Some German verbs require the dative for their direct objects. Common examples are antworten (to answer), danken (to thank), gefallen (to please), folgen (to follow), glauben (to believe), helfen (to help), and raten (to advise). In each case, the direct object of the verb is rendered in the dative. For example: Meine Freunde helfen mir. (My friends help me.) These verbs cannot be used in normal passive constructions, because German allows these only for verbs with accusative objects. It is therefore ungrammatical to say: *Ich werde geholfen. "I am helped." Instead a special construction called "impersonal passive" must be used: Mir wird geholfen, literally: "To me is helped." A colloquial (non-standard) way to form the passive voice for dative verbs is the following: Ich kriege geholfen, or: Ich bekomme geholfen, literally: "I get helped". The use of the verb "to get" here reminds us that the dative case has something to do with giving and receiving. In German, help is not something you perform on somebody, but rather something you offer them. The dative case is also used with reflexive (sich) verbs when specifying what part of the self the verb is being done to: Ich wasche mich. – accusative (I wash myself.) Ich wasche mir die Hände. – dative (I wash my hands, literally "I wash for myself the hands") Cf. the respective accord in French: "Les enfants se sont lavés" (the children have washed themselves) vs. "Les enfants se sont lavé" [uninflected] "les mains" (... their hands). German can use two datives to make sentences like: Sei mir meinem Sohn(e) gnädig! "For my sake, have mercy on my son!" Literally: "Be for me to my son merciful." The first dative mir ("for me") expresses the speaker's commiseration (much like the dativus ethicus in Latin, see below). The second dative meinem Sohn(e) ("to my son") names the actual object of the plea. Mercy is to be given to the son for or on behalf of his mother/father. Adjective endings also change in the dative case. There are three inflection possibilities depending on what precedes the adjective. They most commonly use weak inflection when preceded by a definite article (the), mixed inflection after an indefinite article (a/an), and strong inflection when a quantity is indicated (many green apples). Latin There are several uses for the dative case (): (dative of purpose), e.g. – "[we learn] not for school, but for life", – "to call for help", – "I'm coming for help", – "I receive [this] as a gift" or – "[this] is for the girl's decoration", or "... for decoration for the girl" (as could be either dative or genitive) , which means action for (or against) somebody, e.g., – "to till fields for Greeks"; Combination of and (double dative): "to you for joy" (possessive dative) which means possession, e.g. – literally "to (or for) the angels are wings", this is typically found with a copula and translated as "angels have wings". (ethic dative) indicates that the person in the dative is or should be especially concerned about the action, e.g. "What is Celsus doing for me?" (expressing the speaker being especially interested in what Celsus is doing for him or her); or "Whose interest does this serve?" (literally "To whom does this do good?") , meaning; 'in the eyes of', e.g., 'he seems to me to be a good man'. The dative expresses agency with the gerundive when the gerundive is used to convey obligation or necessity, e.g., , 'these things must be done by us.' Greek Ancient In addition to its main function as the dativus, the dative case has other functions in Classical Greek: (The chart below uses the Latin names for the types of dative; the Greek name for the dative is δοτική πτῶσις, like its Latin equivalent, derived from the verb "to give"; in Ancient Greek, δίδωμι.) Dativus finalis: The dativus finalis, or the 'dative of purpose', is when the dative is used to denote the purpose of a certain action. For example: "" "I fight for the king". "" "I die for honour". Dativus commŏdi (incommodi): The dativus commodi sive incommodi, or the 'dative of benefit (or harm)' is the dative that expresses the advantage or disadvantage of something for someone. For example: For the benefit of: "" (Sophocles, Ajax 1366). "Every man toils for himself". For the harm or disadvantage of: "" (Thucydides 2.12.4). "This day will be the beginning of great sorrows for the Greeks (i.e., for their disadvantage)". Dativus possessivus: The dativus possessivus, or the 'dative of possession' is the dative used to denote the possessor of a certain object or objects. For example: "" (Thucycdides 1.86.3). "For others have a lot of money and ships and horses, but we have good allies (i.e., To others there is a lot of money...)". Dativus ethicus: The dativus ethicus, or the 'ethic or polite dative,' is when the dative is used to signify that the person or thing spoken of is regarded with interest by someone. This dative is mostly, if not exclusively, used in pronouns. As such, it is also called the "dative of pronouns." For example: "" (Demosthenes 18.178). "Pay close attention to this, I beg you (i.e., please pay..)". "" (Xenophon, Cyropaedia 18.178). "Oh, mother, how handsome grandpa is (I've just realized!)". Dativus auctoris: The dativus auctoris, or the 'dative of agent,' is the dative used to denote the doer of an action. Note, however, that in Classical Greek, the agent is usually in the genitive after (by, at the hands of). The agent is in the dative most often with the perfect and pluperfect passive, and with the verbal adjective in . For example: "" (Isocrates 8.39) "Many cures have been discovered by doctors." Dativus instrumenti: The dativus instrumenti, or the 'dative of instrument,' is when the dative is used to denote an instrument or means of a certain action (or, more accurately, as the instrumental case). For example: "." (Homer, Odyssey 9.407) "He kills me with a bait (i.e., by means of a bait)." Dativus modi: The dativus modi, or the 'dative of manner,' is the dative used to describe the manner or way by which something happened. For example: "" (Thucydides 8.84) "having died of (from) a disease." Dativus mensurae: The dativus mensurae, or the 'dative of measurement,' is the dative used to denote the measurement of difference. For example: "" (Plato, Phaedo 101a) "taller by a head." "" (Plato, Laws 729d) "by far the best." The articles in the Greek dative are Modern The dative case, strictly speaking, no longer exists in Modern Greek, except in fossilized expressions like δόξα τω Θεώ (from the ecclesiastical τῷ Θεῷ δόξα, "Glory to God") or εν τάξει (ἐν τάξει, lit. "in order", i.e. "all right" or "OK"). Otherwise, most of the functions of the dative have been subsumed in the accusative. Slavic languages In Russian, the dative case is used for indicating the indirect object of an action (that to which something is given, thrown, read, etc.). In the instance where a person is the goal of motion, dative is used instead of accusative to indicate motion toward. This is usually achieved with the preposition κ + destination in dative case; К врачу, meaning "to the doctor." Dative is also the necessary case taken by certain prepositions when expressing certain ideas. For instance, when the preposition по is used to mean "along," its object is always in dative case, as in По бокам, meaning "along the sides." Other Slavic languages apply the dative case (and the other cases) more or less the same way as does Russian; some languages may use the dative in other ways. The following examples are from Polish: after certain verbs (dziękować komuś "to thank someone", pomóc komuś "to help someone", wierzyć komuś "to believe someone") in certain expressions (Czy podoba ci się piosenka? "Do you like the song?", Jest mi zimno "I'm cold", Jest nam smutno "We're feeling sad", Będzie wam trudniej... "It will be more difficult for you guys"), Śniło jej się, że... "She dreamt that" dativus commodi to indicate action for somebody (Zbuduję temu człowiekowi dom "I will build a house for this person") when something is taken away or something occurs to someone (Zdechł im pies "Their dog died"; Zabrali mu komputer "They took away his computer"; Zepsuł nam się samochód "Our car broke down"; Coś mi się przypomniało "I just remembered something") Some other kinds of dative use as found in the Serbo-Croatian language are: Dativus finalis (Titaniku u pomoć "to Titanic's rescue"), Dativus commodi/incommodi (Operi svojoj majci suđe "Wash the dishes for your mother"), Dativus possessivus (Ovcama je dlaka gusta "Sheep's hair is thick"), Dativus ethicus (Šta mi radi Boni? "What is Boni doing? (I am especially interested in what it is)") and Dativus auctoris (Izgleda mi okej "It seems okay to me"). Unusual in other Indo-European branches but common among Slavic languages, endings of nouns and adjectives are different based on grammatical function. Other factors are gender and number. In some cases, the ending may not be obvious, even when those three factors (function, gender, number) are considered. For example, in Polish, 'syn' ("son") and 'ojciec' ("father") are both masculine singular nouns, yet appear as syn → synowi and ojciec → ojcu in the dative. Baltic languages Both Lithuanian and Latvian have a distinct dative case in the system of nominal declensions. Lithuanian nouns preserve Indo-European inflections in the dative case fairly well: (o-stems) vaikas -> sg. vaikui, pl. vaikams; (ā-stems) ranka -> sg. rankai, pl. rankoms; (i-stems) viltis -> sg. vilčiai, pl. viltims; (u-stems) sūnus -> sg. sūnui, pl. sūnums; (consonant stems) vanduo -> sg. vandeniui, pl. vandenims. Adjectives in the dative case receive pronominal endings (this might be the result of a more recent development): tas geras vaikas -> sg. tam geram vaikui, pl. tiems geriems vaikams. The dative case in Latvian underwent further simplifications – the original masculine endings of both nouns and adjectives have been replaced with pronominal inflections: tas vīrs -> sg. tam vīram, pl. vīriem. Also, the final "s" in all Dative forms has been dropped. The only exception is personal pronouns in the plural: mums (to us), jums (to you). Note that in colloquial Lithuanian the final "s" in the dative is often omitted, as well: time geriem vaikam. In both Latvian and Lithuanian, the main function of the dative case is to render the indirect object in a sentence: (lt) aš duodu vyrui knygą; (lv) es dodu [duodu] vīram grāmatu – I am giving a book to the man. The dative case can also be used with gerundives to	also used with reflexive (sich) verbs when specifying what part of the self the verb is being done to: Ich wasche mich. – accusative (I wash myself.) Ich wasche mir die Hände. – dative (I wash my hands, literally "I wash for myself the hands") Cf. the respective accord in French: "Les enfants se sont lavés" (the children have washed themselves) vs. "Les enfants se sont lavé" [uninflected] "les mains" (... their hands). German can use two datives to make sentences like: Sei mir meinem Sohn(e) gnädig! "For my sake, have mercy on my son!" Literally: "Be for me to my son merciful." The first dative mir ("for me") expresses the speaker's commiseration (much like the dativus ethicus in Latin, see below). The second dative meinem Sohn(e) ("to my son") names the actual object of the plea. Mercy is to be given to the son for or on behalf of his mother/father. Adjective endings also change in the dative case. There are three inflection possibilities depending on what precedes the adjective. They most commonly use weak inflection when preceded by a definite article (the), mixed inflection after an indefinite article (a/an), and strong inflection when a quantity is indicated (many green apples). Latin There are several uses for the dative case (): (dative of purpose), e.g. – "[we learn] not for school, but for life", – "to call for help", – "I'm coming for help", – "I receive [this] as a gift" or – "[this] is for the girl's decoration", or "... for decoration for the girl" (as could be either dative or genitive) , which means action for (or against) somebody, e.g., – "to till fields for Greeks"; Combination of and (double dative): "to you for joy" (possessive dative) which means possession, e.g. – literally "to (or for) the angels are wings", this is typically found with a copula and translated as "angels have wings". (ethic dative) indicates that the person in the dative is or should be especially concerned about the action, e.g. "What is Celsus doing for me?" (expressing the speaker being especially interested in what Celsus is doing for him or her); or "Whose interest does this serve?" (literally "To whom does this do good?") , meaning; 'in the eyes of', e.g., 'he seems to me to be a good man'. The dative expresses agency with the gerundive when the gerundive is used to convey obligation or necessity, e.g., , 'these things must be done by us.' Greek Ancient In addition to its main function as the dativus, the dative case has other functions in Classical Greek: (The chart below uses the Latin names for the types of dative; the Greek name for the dative is δοτική πτῶσις, like its Latin equivalent, derived from the verb "to give"; in Ancient Greek, δίδωμι.) Dativus finalis: The dativus finalis, or the 'dative of purpose', is when the dative is used to denote the purpose of a certain action. For example: "" "I fight for the king". "" "I die for honour". Dativus commŏdi (incommodi): The dativus commodi sive incommodi, or the 'dative of benefit (or harm)' is the dative that expresses the advantage or disadvantage of something for someone. For example: For the benefit of: "" (Sophocles, Ajax 1366). "Every man toils for himself". For the harm or disadvantage of: "" (Thucydides 2.12.4). "This day will be the beginning of great sorrows for the Greeks (i.e., for their disadvantage)". Dativus possessivus: The dativus possessivus, or the 'dative of possession' is the dative used to denote the possessor of a certain object or objects. For example: "" (Thucycdides 1.86.3). "For others have a lot of money and ships and horses, but we have good allies (i.e., To others there is a lot of money...)". Dativus ethicus: The dativus ethicus, or the 'ethic or polite dative,' is when the dative is used to signify that the person or thing spoken of is regarded with interest by someone. This dative is mostly, if not exclusively, used in pronouns. As such, it is also called the "dative of pronouns." For example: "" (Demosthenes 18.178). "Pay close attention to this, I beg you (i.e., please pay..)". "" (Xenophon, Cyropaedia 18.178). "Oh, mother, how handsome grandpa is (I've just realized!)". Dativus auctoris: The dativus auctoris, or the 'dative of agent,' is the dative used to denote the doer of an action. Note, however, that in Classical Greek, the agent is usually in the genitive after (by, at the hands of). The agent is in the dative most often with the perfect and pluperfect passive, and with the verbal adjective in . For example: "" (Isocrates 8.39) "Many cures have been discovered by doctors." Dativus instrumenti: The dativus instrumenti, or the 'dative of instrument,' is when the dative is used to denote an instrument or means of a certain action (or, more accurately, as the instrumental case). For example: "." (Homer, Odyssey 9.407) "He kills me with a bait (i.e., by means of a bait)." Dativus modi: The dativus modi, or the 'dative of manner,' is the dative used to describe the manner or way by which something happened. For example: "" (Thucydides 8.84) "having died of (from) a disease." Dativus mensurae: The dativus mensurae, or the 'dative of measurement,' is the dative used to denote the measurement of difference. For example: "" (Plato, Phaedo 101a) "taller by a head." "" (Plato, Laws 729d) "by far the best." The articles in the Greek dative are Modern The dative case, strictly speaking, no longer exists in Modern Greek, except in fossilized expressions like δόξα τω Θεώ (from the ecclesiastical τῷ Θεῷ δόξα, "Glory to God") or εν τάξει (ἐν τάξει, lit. "in order", i.e. "all right" or "OK"). Otherwise, most of the functions of the dative have been subsumed in the accusative. Slavic languages In Russian, the dative case is used for indicating the indirect object of an action (that to which something is given, thrown, read, etc.). In the instance where a person is the goal of motion, dative is used instead of accusative to indicate motion toward. This is usually achieved with the preposition κ + destination in dative case; К врачу, meaning "to the doctor." Dative is also the necessary case taken by certain prepositions when expressing certain ideas. For instance, when the preposition по is used to mean "along," its object is always in dative case, as in По бокам, meaning "along the sides." Other Slavic languages apply the dative case (and the other cases) more or less the same way as does Russian; some languages may use the dative in other ways. The following examples are from Polish: after certain verbs (dziękować komuś "to thank someone", pomóc komuś "to help someone", wierzyć komuś "to believe someone") in certain expressions (Czy podoba ci się piosenka? "Do you like the song?", Jest mi zimno "I'm cold", Jest nam smutno "We're feeling sad", Będzie wam trudniej... "It will be more difficult for you guys"), Śniło jej się, że... "She dreamt that" dativus commodi to indicate action for somebody (Zbuduję temu człowiekowi dom "I will build a house for this person") when something is taken away or something occurs to someone (Zdechł im pies "Their dog died"; Zabrali mu komputer "They took away his computer"; Zepsuł nam się samochód "Our car broke down"; Coś mi się przypomniało "I just remembered something") Some other kinds of dative use as found in the Serbo-Croatian language are: Dativus finalis (Titaniku u pomoć "to Titanic's rescue"), Dativus commodi/incommodi (Operi svojoj majci suđe "Wash the dishes for your mother"), Dativus possessivus (Ovcama je dlaka gusta "Sheep's hair is thick"), Dativus ethicus (Šta mi radi Boni? "What is Boni doing? (I am especially interested in what it is)") and Dativus auctoris (Izgleda mi okej "It seems okay to me"). Unusual in other Indo-European branches but common among Slavic languages, endings of nouns and adjectives are different based on grammatical function. Other factors are gender and number. In some cases, the ending may not be obvious, even when those three factors (function, gender, number) are considered. For example, in Polish, 'syn' ("son") and 'ojciec' ("father") are both masculine singular nouns, yet appear as syn → synowi and ojciec → ojcu in the dative. Baltic languages Both Lithuanian and Latvian have a distinct dative case in the system of nominal declensions. Lithuanian nouns preserve Indo-European inflections in the dative case fairly well: (o-stems) vaikas -> sg. vaikui, pl. vaikams; (ā-stems) ranka -> sg. rankai, pl. rankoms; (i-stems) viltis -> sg. vilčiai, pl. viltims; (u-stems) sūnus -> sg. sūnui, pl. sūnums; (consonant stems) vanduo -> sg. vandeniui, pl. vandenims. Adjectives in the dative case receive pronominal endings (this might be the result of a more recent development): tas geras vaikas -> sg. tam geram vaikui, pl. tiems geriems vaikams. The dative case in Latvian underwent further simplifications – the original masculine endings of both nouns and adjectives have been replaced with pronominal inflections: tas vīrs -> sg. tam vīram, pl. vīriem. Also, the final "s" in all Dative forms has been dropped. The only exception is personal pronouns in the plural: mums (to us), jums (to you). Note that in colloquial Lithuanian the final "s" in the dative is often omitted, as well: time geriem vaikam. In both Latvian and Lithuanian, the main function of the dative case is to render the indirect object in a sentence: (lt) aš duodu vyrui knygą; (lv) es dodu [duodu] vīram grāmatu – I am giving a book to the man. The dative case can also be used with gerundives to indicate an action preceding or simultaneous with the main action in a sentence: (lt) jam įėjus, visi atsistojo – when he walked in, everybody stood up, lit. to him having walked in, all stood up; (lt) jai miegant, visi dirbo – while she slept, everybody was working, lit. to her sleeping, all were working. In modern standard Lithuanian, Dative case is not required by prepositions, although in many dialects it is done frequently: (dial.) iki (+D) šiai dienai, (stand.) iki (+G) šios dienos – up until this day. In Latvian, the dative case is taken by several prepositions in the singular and all prepositions in the plural (due to peculiar historical changes): sg. bez (+G) tevis (without thee) ~ pl. bez (+D) jums (without you); sg. pa (+A) ceļu (along the road) ~ pl. pa (+D) ceļiem (along the roads). Armenian In modern Eastern Armenian, the dative is attained by adding any article to the genitive: dog = շուն GEN > շան (of the dog; dog's) with no articles DAT > շանը or շանն (to the dog) with definite articles (-ն if preceding a vowel) DAT > մի շան (to a dog) with indefinite article DAT > շանս (to my dog) with 1st person possessive article DAT > շանդ (to your dog) with 2nd person possessive article There is a general tendency to view -ին as the standard dative suffix, but only because that is its most productive (and therefore common) form. The suffix -ին as a dative marker is nothing but the standard, most common, genitive suffix -ի accompanied by the definite article -ն. But the dative
crystal system that are topologically equivalent to the regular dodecahedron but less symmetrical: the pyritohedron with pyritohedral symmetry, and the tetartoid with tetrahedral symmetry: Pyritohedron A pyritohedron is a dodecahedron with pyritohedral (Th) symmetry. Like the regular dodecahedron, it has twelve identical pentagonal faces, with three meeting in each of the 20 vertices (see figure). However, the pentagons are not constrained to be regular, and the underlying atomic arrangement has no true fivefold symmetry axis. Its 30 edges are divided into two sets – containing 24 and 6 edges of the same length. The only axes of rotational symmetry are three mutually perpendicular twofold axes and four threefold axes. Although regular dodecahedra do not exist in crystals, the pyritohedron form occurs in the crystals of the mineral pyrite, and it may be an inspiration for the discovery of the regular Platonic solid form. The true regular dodecahedron can occur as a shape for quasicrystals (such as holmium–magnesium–zinc quasicrystal) with icosahedral symmetry, which includes true fivefold rotation axes. Crystal pyrite The name crystal pyrite comes from one of the two common crystal habits shown by pyrite (the other one being the cube). In pyritohedral pyrite, the faces have a Miller index of (210), which means that the dihedral angle is 2·arctan(2) ≈ 126.87° and each pentagonal face has one angle of approximately 121.6° in between two angles of approximately 106.6° and opposite two angles of approximately 102.6°. The following formulas show the measurements for the face of a perfect crystal (which is rarely found in nature). Cartesian coordinates The eight vertices of a cube have the coordinates (±1, ±1, ±1). The coordinates of the 12 additional vertices are (0, ±(1 + h), ±(1 − h2)), (±(1 + h), ±(1 − h2), 0) and (±(1 − h2), 0, ±(1 + h)). h is the height of the wedge-shaped "roof" above the faces of that cube with edge length 2. An important case is h = (a quarter of the cube edge length) for perfect natural pyrite (also the pyritohedron in the Weaire–Phelan structure). Another one is h = = 0.618... for the regular dodecahedron. See section Geometric freedom for other cases. Two pyritohedra with swapped nonzero coordinates are in dual positions to each other like the dodecahedra in the compound of two dodecahedra. Geometric freedom The pyritohedron has a geometric degree of freedom with limiting cases of a cubic convex hull at one limit of collinear edges, and a rhombic dodecahedron as the other limit as 6 edges are degenerated to length zero. The regular dodecahedron represents a special intermediate case where all edges and angles are equal. It is possible to go past these limiting cases, creating concave or nonconvex pyritohedra. The endo-dodecahedron is concave and equilateral; it can tessellate space with the convex regular dodecahedron. Continuing from there in that direction, we pass through a degenerate case where twelve vertices coincide in the centre, and on to the regular great stellated dodecahedron where all edges and angles are equal again, and the faces have been distorted into regular pentagrams. On the other side, past the rhombic dodecahedron, we get a nonconvex equilateral dodecahedron with fish-shaped self-intersecting equilateral pentagonal faces. Tetartoid A tetartoid (also tetragonal pentagonal dodecahedron, pentagon-tritetrahedron, and tetrahedric pentagon dodecahedron) is a dodecahedron with chiral tetrahedral symmetry (T). Like the regular dodecahedron, it has twelve identical pentagonal faces, with three meeting in each of the 20 vertices. However, the pentagons are not regular and the figure has no fivefold symmetry axes. Although regular dodecahedra do not exist in crystals, the tetartoid form does. The name tetartoid comes from the Greek root for one-fourth because it has one fourth of full octahedral symmetry, and half of pyritohedral symmetry. The mineral cobaltite can have this symmetry form. Abstractions sharing the solid's topology and symmetry can be created from the cube and the tetrahedron. In the cube each face is bisected by a slanted edge. In the tetrahedron each edge is trisected, and each of the new vertices connected to a face center. (In Conway polyhedron notation this is a gyro tetrahedron.) Cartesian coordinates The following points are vertices of a tetartoid pentagon under tetrahedral symmetry: (a, b, c); (−a, −b, c); (−, −, ); (−c, −a, b); (−, , ), under the following conditions: , n = a2c − bc2, d1 = a2 − ab + b2 + ac − 2bc, d2 = a2 + ab + b2 − ac − 2bc, . Geometric freedom The regular dodecahedron is a tetartoid with more than the required symmetry. The triakis tetrahedron is a degenerate case with 12 zero-length edges. (In terms of the colors used above this means, that the white vertices and green edges are absorbed by the green vertices.) Dual of triangular gyrobianticupola A lower symmetry form of the regular dodecahedron can be constructed as the dual of a polyhedra constructed from two triangular anticupola connected base-to-base, called a triangular gyrobianticupola. It has D3d symmetry, order 12. It has 2 sets of 3 identical pentagons on the top and bottom, connected 6 pentagons around the sides which alternate upwards and downwards. This form has a hexagonal cross-section and identical copies can be connected as a partial hexagonal honeycomb,	combinatorial structure as the regular dodecahedron (in terms of the graph formed by its vertices and edges), but their pentagonal faces are not regular: The pyritohedron, a common crystal form in pyrite, has pyritohedral symmetry, while the tetartoid has tetrahedral symmetry. The rhombic dodecahedron can be seen as a limiting case of the pyritohedron, and it has octahedral symmetry. The elongated dodecahedron and trapezo-rhombic dodecahedron variations, along with the rhombic dodecahedra, are space-filling. There are numerous other dodecahedra. While the regular dodecahedron shares many features with other Platonic solids, one unique property of it is that one can start at a corner of the surface and draw an infinite number of straight lines across the figure that return to the original point without crossing over any other corner. Regular dodecahedra The convex regular dodecahedron is one of the five regular Platonic solids and can be represented by its Schläfli symbol {5, 3}. The dual polyhedron is the regular icosahedron {3, 5}, having five equilateral triangles around each vertex. The convex regular dodecahedron also has three stellations, all of which are regular star dodecahedra. They form three of the four Kepler–Poinsot polyhedra. They are the small stellated dodecahedron {5/2, 5}, the great dodecahedron {5, 5/2}, and the great stellated dodecahedron {5/2, 3}. The small stellated dodecahedron and great dodecahedron are dual to each other; the great stellated dodecahedron is dual to the great icosahedron {3, 5/2}. All of these regular star dodecahedra have regular pentagonal or pentagrammic faces. The convex regular dodecahedron and great stellated dodecahedron are different realisations of the same abstract regular polyhedron; the small stellated dodecahedron and great dodecahedron are different realisations of another abstract regular polyhedron. Other pentagonal dodecahedra In crystallography, two important dodecahedra can occur as crystal forms in some symmetry classes of the cubic crystal system that are topologically equivalent to the regular dodecahedron but less symmetrical: the pyritohedron with pyritohedral symmetry, and the tetartoid with tetrahedral symmetry: Pyritohedron A pyritohedron is a dodecahedron with pyritohedral (Th) symmetry. Like the regular dodecahedron, it has twelve identical pentagonal faces, with three meeting in each of the 20 vertices (see figure). However, the pentagons are not constrained to be regular, and the underlying atomic arrangement has no true fivefold symmetry axis. Its 30 edges are divided into two sets – containing 24 and 6 edges of the same length. The only axes of rotational symmetry are three mutually perpendicular twofold axes and four threefold axes. Although regular dodecahedra do not exist in crystals, the pyritohedron form occurs in the crystals of the mineral pyrite, and it may be an inspiration for the discovery of the regular Platonic solid form. The true regular dodecahedron can occur as a shape for quasicrystals (such as holmium–magnesium–zinc quasicrystal) with icosahedral symmetry, which includes true fivefold rotation axes. Crystal pyrite The name crystal pyrite comes from one of the two common crystal habits shown by pyrite (the other one being the cube). In pyritohedral pyrite, the faces have a Miller index of (210), which means that the dihedral angle is 2·arctan(2) ≈ 126.87° and each pentagonal face has one angle of approximately 121.6° in between two angles of approximately 106.6° and opposite two angles of approximately 102.6°. The following formulas show the measurements for the face of a perfect crystal (which is rarely found in nature). Cartesian coordinates The eight vertices of a cube have the coordinates (±1, ±1, ±1). The coordinates of the 12 additional vertices are (0, ±(1 + h), ±(1 − h2)), (±(1 + h), ±(1 − h2), 0) and (±(1 − h2), 0, ±(1 + h)). h is the height of the wedge-shaped "roof" above the faces of that cube with edge length
on 17 December 1918. Led by Harold Nelson, some 1,000 demonstrators marched to Government House at Liberty Square in Darwin where they burnt an effigy of the Administrator of the Northern Territory John Gilruth and demanded his resignation. The incident became known as the Darwin Rebellion. Their grievances were against the two main Northern Territory employers: Vestey's Meatworks and the federal government. Both Gilruth and the Vestey company left Darwin soon afterwards. On 18 October 1918, during the Spanish flu pandemic, the SS Mataram sailing from Singapore with infectious diseases arrived in Darwin. Around 10,000 Australian and other Allied troops arrived in Darwin at the outset of World War II, to defend Australia's northern coastline. On 19 February 1942 at 0957, 188 Japanese warplanes attacked Darwin in two waves. It was the same fleet that had bombed Pearl Harbor, though a considerably larger number of bombs were dropped on Darwin than on Pearl Harbor. The attack killed at least 243 people and caused immense damage to the town, airfields, and aircraft. These were by far the most serious attacks on Australia in time of war, in terms of fatalities and damage. They were the first of many raids on Darwin. Darwin was further developed after the war, with sealed roads constructed connecting the region to Alice Springs to the south and Mount Isa to the south-east, and Manton Dam built in the south to provide the city with water. On Australia Day (26 January) 1959, Darwin was granted city status. 1970–present day On 25 December 1974, Darwin was struck by Cyclone Tracy, which killed 71 people and destroyed over 70% of the city's buildings, including many old stone buildings such as the Palmerston Town Hall, which could not withstand the lateral forces generated by the strong winds. After the disaster, 30,000 people of the population of 46,000 were evacuated, in what turned out to be the biggest airlift in Australia's history. The town was subsequently rebuilt with newer materials and techniques during the late 1970s by the Darwin Reconstruction Commission, led by former Brisbane Lord mayor Clem Jones. A satellite city of Palmerston was built east of Darwin in the early 1980s. On 17 September 2003 the Adelaide–Darwin railway was completed, with the opening of the Alice Springs-Darwin standard-gauge line. Aviation history Darwin has played host to many of aviation's early pioneers. On 10 December 1919 Captain Ross Smith and his crew landed in Darwin and won a £10,000 Prize from the Australian Government for completing the first flight from London to Australia in under thirty days. Smith and his Crew flew a Vickers Vimy, G-EAOU, and landed on an airstrip that has now become Ross Smith Avenue. Other aviation pioneers include Amy Johnson, Amelia Earhart, Sir Charles Kingsford Smith and Bert Hinkler. The original QANTAS Empire Airways Ltd Hangar, a registered heritage site, was part of the original Darwin Civil Aerodrome in Parap and is now a museum and still bears scars from the bombing of Darwin during World War II. Darwin was home to Australian and US pilots during the war, with airstrips built in and around Darwin. Today Darwin provides a staging ground for military exercises. Darwin was a compulsory stopover and checkpoint in the London-to-Melbourne Centenary Air Race in 1934. The official name of the race was the MacRobertson Air Race. Winners of the race were Tom Campbell Black and C. W. A. Scott. The following is an excerpt from Time magazine, 29 October 1934: The Australian Aviation Heritage Centre is approximately from the city centre on the Stuart Highway and is one of only two places outside the United States where a B-52 bomber (on permanent loan from the United States Air Force) is on public display. Geography Darwin is a coastal city, situated along the western shoreline of the Northern Territory. The water meets the land from the Beagle Gulf, which extends out into the Timor Sea. The central business district occupies a low bluff overlooking Darwin Harbour; it is flanked by Frances Bay to the east, and Cullen Bay to the west. The remainder of the city is relatively flat and low-lying, and areas bordering the coast are home to recreational reserves, extensive beaches, and excellent fishing. City and suburbs Darwin and its suburbs spread in an approximately triangular shape, with the older south-western suburbs—and the city itself—forming one corner, the newer northern suburbs another, and the eastern suburbs, progressing towards Palmerston, forming the third. The older part of Darwin is separated from the newer northern suburbs by Darwin International Airport and RAAF Base Darwin. Palmerston is a satellite city east of Darwin that was established in the 1980s and is one of the fastest-growing municipalities in Australia. The rural areas of Darwin including Howard Springs, Humpty Doo and Berry Springs are experiencing strong growth. Darwin's central business district (CBD) is bounded by Daly Street in the north-west, McMinn Street in the north-east, Mitchell Street on the south-west, and Bennett Street on the south-east. The CBD has been the focus of a number of major projects, including the billion-dollar redevelopment of the Stokes Hill wharf waterfront area including a convention centre with seating for 1500 people and approximately of exhibition space. The developers announced that this includes hotels, residential apartments, and public space. The city's main industrial areas are along the Stuart Highway going towards Palmerston, centred on Winnellie. The largest shopping precinct in the area is Casuarina Square. The most expensive residential areas stand along the coast in suburbs such as the marina of Cullen Bay part of Larrakeyah, Bayview and Brinkin, despite the risk these low-lying regions face during cyclones and higher tides, adequate drainage and stringent building regulations have reduced the potential damage to buildings or injury to residents. The inner northern suburbs are home to lower-income households, although low-income Territory Housing units are scattered throughout the metropolitan area. The suburb of Lyons was part of a multi-stage land release and development in the Northern Suburbs; planning, development and construction took place from 2004 to 2009. More recent developments near Lyons subdivision includes the suburb of Muirhead. Climate Darwin has a tropical savanna climate (Köppen Aw) with distinct wet and dry seasons and the average maximum temperature is similar all year round. The dry season runs from about May to September, during which nearly every day is sunny, and afternoon relative humidity averages around 30%. The driest period of the year, seeing only approximately of monthly rainfall on average, is between May and September. In the coolest months of June and July, the daily minimum temperature may dip as low as , but very rarely lower, and a temperature lower than has never been recorded in the city centre. Outer suburbs away from the coast, however, can occasionally record temperatures as low as in the dry season. For a 147‑day period during the 2012 dry season, from 5 May to 29 September, Darwin recorded no precipitation whatsoever. Prolonged periods of no precipitation are common in the dry season in Northern Australia (particularly in the Northern Territory and northern regions of Western Australia), although a no-rainfall event of this extent is rare. The 3pm dewpoint average in the wet season is at around . Extreme temperatures at the Darwin Post Office Station have ranged from on 17 October 1892 to on 25 June 1891; while extreme temperatures at the Darwin Airport station (which is further from the coast and routinely records cooler temperatures than the post office station, which is in Darwin's CBD) have ranged from on 18 October 1982 to on 29 July 1942. The highest minimum temperature on record is on 18 January 1928 for the post office station and on both 25 November 1987 and 17 December 2014 for the airport station, while the lowest maximum temperature on record is on 3 June 1904 for the post office station and on 14 July 1968 for the airport station. The wet season is associated with tropical cyclones and monsoon rains. The majority of rainfall occurs between December and March (the southern hemisphere summer), when thunderstorms are common and afternoon relative humidity averages over 70 percent during the wettest months. It does not rain every day during the wet season, but most days have plentiful cloud cover; January averages under 6 hours of bright sunshine daily. Darwin's highest Bureau of Meteorology verified daily rainfall total is , which fell when Cyclone Carlos bore down on the Darwin area on 16 February 2011. February 2011 was also Darwin's wettest month ever recorded, with recorded for the month at the airport. The hottest months are October and November, just before the onset of the main rain season. The heat index sometimes rises above , while the actual temperature is usually below , because of humidity levels that most would find uncomfortable. Because of its long dry season, Darwin has the second-highest average daily hours of sunshine (8.4) of any Australian capital, with the most sunshine from April to November; only Perth, Western Australia, averages more (8.8). The sun passes directly overhead in mid-October and mid-February. The average temperature of the sea ranges from in July to in December. Darwin occupies one of the most lightning-prone areas in Australia. On 31 January 2002 an early-morning squall line produced over 5,000 cloud-to-ground lightning strikes within a radius of Darwin alone—about three times the amount of lightning that Perth, Western Australia, experiences on average in an entire year. Demographics In 2011, the Darwin population averaged 33 years old (compared to the national average of around 37 years) assisted to a large extent by the military presence and the fact that many people opt to retire elsewhere. Ancestry and immigration Darwin's population changed after the Second World War. Darwin, like many other Australian cities, experienced influxes from Europe, with significant numbers of Italians and Greeks during the 1960s and 1970s. Darwin also started to experience an influx from other European countries, which included the Dutch, Germans, and many others. A significant percentage of Darwin's residents are recent immigrants from Asia, including the peoples of East Timor. At the 2016 census, the most commonly nominated ancestries were: 38.3% of the population at the 2016 census was born overseas. The five largest groups of overseas-born were from the Philippines (3.6%), England (3.1%), New Zealand (2.1%), India (2%) and Greece (0.9%). 8.7% of the population, or 11,960 people, identified as Indigenous Australians (Aboriginal Australians and Torres Strait Islanders) in 2016. This is the largest proportion of any Australian capital city. Language At the 2016 census, 58% of the population spoke only English at home. Other languages spoken at home include Tagalog (3.7%), Greek, (3.5%), Mandarin (2.0%), Nepali (1.2%), Indonesian (1.0%), Australian Aboriginal languages (1.0%), Malayalam (0.9%), Vietnamese (0.8%), Cantonese (0.7%), Italian (0.6%), Portuguese (0.5%, mostly spoken by Timorese), and Tamil (0.5%). Religion Christianity has the most adherents in Darwin, with 56,613 followers accounting for 49.5 percent of the population of the city. The largest denominations of Christianity are Roman Catholicism (24,538 or 21.5 percent), Anglicanism (14,028 or 12.3 percent) and Greek Orthodoxy (2,964 or 2.6 percent). Buddhists, Muslims, Hindus and Jews account for 3.2 percent of Darwin's population. There were 26,695 or 23.3 percent of people professing no religion. Law and government The Darwin City Council (incorporated under the Northern Territory Local Government Act 1993) governs the City of Darwin, which takes in the CBD and the suburbs. The city has been governed by a city council form of government since 1957. The council consists of 13 elected members, the lord mayor, and 12 aldermen. The City of Darwin electorate is organised into four electoral units or wards. The wards are Chan, Lyons, Richardson, and Waters. The constituents of each ward are directly responsible for electing three aldermen. Constituents of all wards are directly responsible for electing the Lord Mayor of Darwin. The mayor is Kon Vatskalis after council elections in August 2017. The rest of the Darwin area is divided into two local government areas—the Palmerston City Council and the Shire of Coomalie. These areas have elected councils that are responsible for functions delegated to them by the Northern Territory Government, such as planning and garbage collection. The Legislative Assembly of the Northern Territory convenes in Darwin in the Northern Territory Parliament House. Government House, the official residence of the Administrator of the Northern Territory, is on the Esplanade. Darwin is split between nine electoral divisions in the Legislative Assembly—Port Darwin, Fannie Bay, Fong Lim, Nightcliff, Sanderson, Johnston, Casuarina, Wanguri, and Karama. Historically, Darwin voters elected Country Liberal Party members. However, since the turn of the 21st century, voters have often selected Labor members, particularly in the more diverse northern section. Also on the Esplanade is the Supreme Court of the Northern Territory. Darwin has a Magistrate's Court which is on the corner of Cavenagh and Bennett streets, quite close to the Darwin City Council Chambers. Crime Darwin's police force are members of the Northern Territory Police Force, under the NT Police Darwin Metropolitan Command. The Darwin urban centre includes Darwin City and the associated suburbs from Buffalo Creek, Berrimah, and East Arm westwards, representing around 35% of the Northern Territory's population. Palmerston urban centre closely approximates the Palmerston Local Government Area, and represents approximately 13% of the Northern Territory's population. Darwin has had a history of alcohol abuse and violent crime, with 6,000 assaults in 2009, of which 350 resulted in broken jaws and noses—more than anywhere else in the world, according to the Royal Darwin Hospital. Mitchell Street, with its numerous pubs, clubs and other entertainment venues, was one of the areas policed by the CitySafe Unit, officially launched by the NT Chief Minister Paul Henderson on 25 February 2009. It was credited with success in tackling alcohol abuse linked to crime, and the NT police were looking at establishing a specialist licensing enforcement unit in 2010. The First Response Patrol, run by Larrakia Nation, which helps to move homeless Indigenous women out of dangerous situations, was credited with the fall in sexual assaults in 2009. The service operates every day from 5am to 2am. Recent trends In the 10 months between 1 October 2018, the date that the alcohol floor price and various other measures were imposed by the NT government following the Riley Review, and 31 July 2019, alcohol-related assaults dropped by 16% and domestic violence by 9% in the Darwin area. The rate of offending in most categories of crime dropped in the Darwin urban area between 2018 and 2019, with the notable exceptions of motor vehicle theft and break-ins (both up about 12%). Apart from sexual assault, which rose from 21 to 46, all other categories of crime showed drops in Palmerston. Economy The two largest economic sectors are mining and tourism. Given its location, Darwin serves as a gateway for Australian travellers to Asia. Mining and energy industry production exceeds $2.5 billion per annum. The most important mineral resources are gold, zinc, and bauxite, along with manganese and many others. The energy production is mostly off-shore with oil and natural gas from the Timor Sea, although there are significant uranium deposits near Darwin. Tourism employs 8% of Darwin residents and is expected to grow as domestic and international tourists are now spending time in Darwin during the Wet and Dry seasons. Federal spending is also a major contributor to the local economy. Darwin's importance as a port is expected to grow, due to the increased exploitation of petroleum in the nearby Timor Sea and to the completion of the railway link and continued expansion in trade with Asia. During 2005, a number of major construction projects started in Darwin. One is the redevelopment of the Wharf Precinct, which includes a large convention and exhibition centre, apartment housing including Outrigger Pandanas and Evolution on Gardiner, retail and entertainment outlets including a large wave pool and safe swimming lagoon. The Chinatown project has also started with plans to construct Chinese-themed retail and dining outlets. Tourism Tourism is one of Darwin's largest industries and a major employment sector for the Northern Territory. In 2005–2006, 1.38 million people visited the Northern Territory. They stayed for 9.2 million nights and spent over $1.5 billion. The tourism industry directly employed 8,391 Territorians in June 2006, and, when indirect employment is included, tourism typically accounts for more than 14,000 jobs across the Territory. Darwin is a hub for tours to Kakadu National Park, Litchfield National Park and Katherine Gorge. The Territory is traditionally divided into the wet and dry, but there are up to six traditional seasons in Darwin. It is warm and sunny from May to September. Humidity rises during the green season, from October to April bringing thunderstorms and monsoonal rains which rejuvenates the landscape. Tourism is largely seasonal with most tourists visiting during the cooler dry season which runs from April to September. Military The military presence that is maintained both within Darwin, and the wider Northern Territory, is a substantial source of employment. On 16 November 2011, Prime Minister Julia Gillard and President Barack Obama announced that the United States would station troops in Australia for the first time since World War II. The agreement between the United States and Australia would involve a contingent of 250 Marines arriving in Darwin in 2012, with the total number rising to a maximum of 2,500 troops by 2017 on six-month rotations as well as a supporting air element including F-22 Raptors, F-35 Joint Strike Fighters and KC-135 refuellers. China and Indonesia have expressed concern about the decision. Some analysts have argued that an expanded U.S. presence could pose a threat to security. Gillard announced that the first 200 U.S. Marines had arrived in Darwin from Hawaii on late 3 April 2012. In 2013, further news of other expansion vectors was aired in US media, with no comment or confirmation from Australian authorities. The agreement between the two governments remains hidden from public scrutiny. Marine numbers based in Darwin increased to more than 1,150 troops by 2014. In a 2019 telephone survey of local residents, 51% of respondents had positive feelings about the U.S. troop presence, with 6% responding negatively. In late 2021, the US Department of Defense signed a contract to create a fuel storage facility at East Arm. Darwin hosts biennial multi-nation exercises named "Pitch Black"; in 2014 this involved military personnel from Australia, New Zealand, Singapore, Thailand, United Arab Emirates, and the United States. Education Education is overseen territory-wide by the Department of Education and Training (DET), whose role is to continually improve education outcomes for all students, with a focus on Indigenous students. Preschool, primary and secondary Darwin is served by a number of public and private schools that cater to local and overseas students. Over 16,500 primary and secondary students are enrolled in schools in Darwin, with 10,524 students attending primary education, and 5,932 students attending secondary education.	to be repelled by the Tiwi peoples. The Dutch created the first European maps of the area. This accounts for the Dutch names in the area, such as Arnhem Land and Groote Eylandt. The first British person to see Darwin harbour appears to have been Lieutenant John Lort Stokes of on 9 September 1839. The ship's captain, Commander John Clements Wickham, named the port after Charles Darwin, the British naturalist who had sailed with them both on the earlier second expedition of the Beagle. In 1863, the Northern Territory was transferred from New South Wales to South Australia. In 1864 South Australia sent B. T. Finniss north as Government Resident to survey and found a capital for its new territory. Finniss chose a site at Escape Cliffs, near the entrance to Adelaide River, about northeast of the modern city. This attempt was short-lived, however, and the settlement abandoned by 1865. On 5 February 1869, George Goyder, the Surveyor-General of South Australia, established a small settlement of 135 people at Port Darwin between Fort Hill and the escarpment. Goyder named the settlement Palmerston after the British Prime Minister Lord Palmerston. In 1870, the first poles for the Overland Telegraph were erected in Darwin, connecting Australia to the rest of the world. The discovery of gold by employees of the Australian Overland Telegraph Line digging holes for telegraph poles at Pine Creek in the 1880s spawned a gold rush, which further boosted the young colony's development. In February 1872 the brigantine Alexandra was the first private vessel to sail from an English port directly to Darwin, carrying people many of whom were coming to recent gold finds. In early 1875 Darwin's white population had grown to approximately 300 because of the gold rush. On 17 February 1875 the left Darwin en route for Adelaide. The approximately 88 passengers and 34 crew (surviving records vary) included government officials, circuit-court judges, Darwin residents taking their first furlough, and miners. While travelling south along the north Queensland coast, the Gothenburg encountered a cyclone-strength storm and was wrecked on a section of the Great Barrier Reef. Only 22 men survived, while between 98 and 112 people perished. Many passengers who perished were Darwin residents and news of the tragedy severely affected the small community, which reportedly took several years to recover. In the 1870s, relatively large numbers of Chinese settled at least temporarily in the Northern Territory; many were contracted to work the goldfields and later to build the Palmerston to Pine Creek railway. By 1888 there were 6122 Chinese in the Northern Territory, mostly in or around Darwin. The early Chinese settlers were mainly from the Guangdong Province in south China. However, at the end of the nineteenth century anti-Chinese feelings grew in response to the 1890s economic depression, and the White Australia policy meant many Chinese left the territory. However, some families stayed, became British subjects, and established a commercial base in Darwin. Early 20th century The Northern Territory was initially settled and administered by South Australia, until its transfer to the Commonwealth in 1911. In the same year, the city's official name changed from Palmerston to Darwin. The period between 1911 and 1919 was filled with political turmoil, particularly with trade union unrest, which culminated on 17 December 1918. Led by Harold Nelson, some 1,000 demonstrators marched to Government House at Liberty Square in Darwin where they burnt an effigy of the Administrator of the Northern Territory John Gilruth and demanded his resignation. The incident became known as the Darwin Rebellion. Their grievances were against the two main Northern Territory employers: Vestey's Meatworks and the federal government. Both Gilruth and the Vestey company left Darwin soon afterwards. On 18 October 1918, during the Spanish flu pandemic, the SS Mataram sailing from Singapore with infectious diseases arrived in Darwin. Around 10,000 Australian and other Allied troops arrived in Darwin at the outset of World War II, to defend Australia's northern coastline. On 19 February 1942 at 0957, 188 Japanese warplanes attacked Darwin in two waves. It was the same fleet that had bombed Pearl Harbor, though a considerably larger number of bombs were dropped on Darwin than on Pearl Harbor. The attack killed at least 243 people and caused immense damage to the town, airfields, and aircraft. These were by far the most serious attacks on Australia in time of war, in terms of fatalities and damage. They were the first of many raids on Darwin. Darwin was further developed after the war, with sealed roads constructed connecting the region to Alice Springs to the south and Mount Isa to the south-east, and Manton Dam built in the south to provide the city with water. On Australia Day (26 January) 1959, Darwin was granted city status. 1970–present day On 25 December 1974, Darwin was struck by Cyclone Tracy, which killed 71 people and destroyed over 70% of the city's buildings, including many old stone buildings such as the Palmerston Town Hall, which could not withstand the lateral forces generated by the strong winds. After the disaster, 30,000 people of the population of 46,000 were evacuated, in what turned out to be the biggest airlift in Australia's history. The town was subsequently rebuilt with newer materials and techniques during the late 1970s by the Darwin Reconstruction Commission, led by former Brisbane Lord mayor Clem Jones. A satellite city of Palmerston was built east of Darwin in the early 1980s. On 17 September 2003 the Adelaide–Darwin railway was completed, with the opening of the Alice Springs-Darwin standard-gauge line. Aviation history Darwin has played host to many of aviation's early pioneers. On 10 December 1919 Captain Ross Smith and his crew landed in Darwin and won a £10,000 Prize from the Australian Government for completing the first flight from London to Australia in under thirty days. Smith and his Crew flew a Vickers Vimy, G-EAOU, and landed on an airstrip that has now become Ross Smith Avenue. Other aviation pioneers include Amy Johnson, Amelia Earhart, Sir Charles Kingsford Smith and Bert Hinkler. The original QANTAS Empire Airways Ltd Hangar, a registered heritage site, was part of the original Darwin Civil Aerodrome in Parap and is now a museum and still bears scars from the bombing of Darwin during World War II. Darwin was home to Australian and US pilots during the war, with airstrips built in and around Darwin. Today Darwin provides a staging ground for military exercises. Darwin was a compulsory stopover and checkpoint in the London-to-Melbourne Centenary Air Race in 1934. The official name of the race was the MacRobertson Air Race. Winners of the race were Tom Campbell Black and C. W. A. Scott. The following is an excerpt from Time magazine, 29 October 1934: The Australian Aviation Heritage Centre is approximately from the city centre on the Stuart Highway and is one of only two places outside the United States where a B-52 bomber (on permanent loan from the United States Air Force) is on public display. Geography Darwin is a coastal city, situated along the western shoreline of the Northern Territory. The water meets the land from the Beagle Gulf, which extends out into the Timor Sea. The central business district occupies a low bluff overlooking Darwin Harbour; it is flanked by Frances Bay to the east, and Cullen Bay to the west. The remainder of the city is relatively flat and low-lying, and areas bordering the coast are home to recreational reserves, extensive beaches, and excellent fishing. City and suburbs Darwin and its suburbs spread in an approximately triangular shape, with the older south-western suburbs—and the city itself—forming one corner, the newer northern suburbs another, and the eastern suburbs, progressing towards Palmerston, forming the third. The older part of Darwin is separated from the newer northern suburbs by Darwin International Airport and RAAF Base Darwin. Palmerston is a satellite city east of Darwin that was established in the 1980s and is one of the fastest-growing municipalities in Australia. The rural areas of Darwin including Howard Springs, Humpty Doo and Berry Springs are experiencing strong growth. Darwin's central business district (CBD) is bounded by Daly Street in the north-west, McMinn Street in the north-east, Mitchell Street on the south-west, and Bennett Street on the south-east. The CBD has been the focus of a number of major projects, including the billion-dollar redevelopment of the Stokes Hill wharf waterfront area including a convention centre with seating for 1500 people and approximately of exhibition space. The developers announced that this includes hotels, residential apartments, and public space. The city's main industrial areas are along the Stuart Highway going towards Palmerston, centred on Winnellie. The largest shopping precinct in the area is Casuarina Square. The most expensive residential areas stand along the coast in suburbs such as the marina of Cullen Bay part of Larrakeyah, Bayview and Brinkin, despite the risk these low-lying regions face during cyclones and higher tides, adequate drainage and stringent building regulations have reduced the potential damage to buildings or injury to residents. The inner northern suburbs are home to lower-income households, although low-income Territory Housing units are scattered throughout the metropolitan area. The suburb of Lyons was part of a multi-stage land release and development in the Northern Suburbs; planning, development and construction took place from 2004 to 2009. More recent developments near Lyons subdivision includes the suburb of Muirhead. Climate Darwin has a tropical savanna climate (Köppen Aw) with distinct wet and dry seasons and the average maximum temperature is similar all year round. The dry season runs from about May to September, during which nearly every day is sunny, and afternoon relative humidity averages around 30%. The driest period of the year, seeing only approximately of monthly rainfall on average, is between May and September. In the coolest months of June and July, the daily minimum temperature may dip as low as , but very rarely lower, and a temperature lower than has never been recorded in the city centre. Outer suburbs away from the coast, however, can occasionally record temperatures as low as in the dry season. For a 147‑day period during the 2012 dry season, from 5 May to 29 September, Darwin recorded no precipitation whatsoever. Prolonged periods of no precipitation are common in the dry season in Northern Australia (particularly in the Northern Territory and northern regions of Western Australia), although a no-rainfall event of this extent is rare. The 3pm dewpoint average in the wet season is at around . Extreme temperatures at the Darwin Post Office Station have ranged from on 17 October 1892 to on 25 June 1891; while extreme temperatures at the Darwin Airport station (which is further from the coast and routinely records cooler temperatures than the post office station, which is in Darwin's CBD) have ranged from on 18 October 1982 to on 29 July 1942. The highest minimum temperature on record is on 18 January 1928 for the post office station and on both 25 November 1987 and 17 December 2014 for the airport station, while the lowest maximum temperature on record is on 3 June 1904 for the post office station and on 14 July 1968 for the airport station. The wet season is associated with tropical cyclones and monsoon rains. The majority of rainfall occurs between December and March (the southern hemisphere summer), when thunderstorms are common and afternoon relative humidity averages over 70 percent during the wettest months. It does not rain every day during the wet season, but most days have plentiful cloud cover; January averages under 6 hours of bright sunshine daily. Darwin's highest Bureau of Meteorology verified daily rainfall total is , which fell when Cyclone Carlos bore down on the Darwin area on 16 February 2011. February 2011 was also Darwin's wettest month ever recorded, with recorded for the month at the airport. The hottest months are October and November, just before the onset of the main rain season. The heat index sometimes rises above , while the actual temperature is usually below , because of humidity levels that most would find uncomfortable. Because of its long dry season, Darwin has the second-highest average daily hours of sunshine (8.4) of any Australian capital, with the most sunshine from April to November; only Perth, Western Australia, averages more (8.8). The sun passes directly overhead in mid-October and mid-February. The average temperature of the sea ranges from in July to in December. Darwin occupies one of the most lightning-prone areas in Australia. On 31 January 2002 an early-morning squall line produced over 5,000 cloud-to-ground lightning strikes within a radius of Darwin alone—about three times the amount of lightning that Perth, Western Australia, experiences on average in an entire year. Demographics In 2011, the Darwin population averaged 33 years old (compared to the national average of around 37 years) assisted to a large extent by the military presence and the fact that many people opt to retire elsewhere. Ancestry and immigration Darwin's population changed after the Second World War. Darwin, like many other Australian cities, experienced influxes from Europe, with significant numbers of Italians and Greeks during the 1960s and 1970s. Darwin also started to experience an influx from other European countries, which included the Dutch, Germans, and many others. A significant percentage of Darwin's residents are recent immigrants from Asia, including the peoples of East Timor. At the 2016 census, the most commonly nominated ancestries were: 38.3% of the population at the 2016 census was born overseas. The five largest groups of overseas-born were from the Philippines (3.6%), England (3.1%), New Zealand (2.1%), India (2%) and Greece (0.9%). 8.7% of the population, or 11,960 people, identified as Indigenous Australians (Aboriginal Australians and Torres Strait Islanders) in 2016. This is the largest proportion of any Australian capital city. Language At the 2016 census, 58% of the population spoke only English at home. Other languages spoken at home include Tagalog (3.7%), Greek, (3.5%), Mandarin (2.0%), Nepali (1.2%), Indonesian (1.0%), Australian Aboriginal languages (1.0%), Malayalam (0.9%), Vietnamese (0.8%), Cantonese (0.7%), Italian (0.6%), Portuguese (0.5%, mostly spoken by Timorese), and Tamil (0.5%). Religion Christianity has the most adherents in Darwin, with 56,613 followers accounting for 49.5 percent
sole power for a limited duration. At the end of the term, the Dictator's power was returned to normal Consular rule, though not all dictators accepted a return to power sharing. The term started to get its modern negative meaning with Cornelius Sulla's ascension to the dictatorship following Sulla's civil war, making himself the first Dictator in Rome in more than a century (during which the office was ostensibly abolished) as well as de facto eliminating the time limit and need of senatorial acclamation. He avoided a major constitutional crisis by resigning the office after about one year, dying a few years later. Julius Caesar followed Sulla's example in 49 BC and in February 44 BC was proclaimed Dictator perpetuo, "Dictator in perpetuity", officially doing away with any limitations on his power, which he kept until his assassination the following month. Following Caesar's assassination, his heir Augustus was offered the title of dictator, but he declined it. Later successors also declined the title of dictator, and usage of the title soon diminished among Roman rulers. The term comes from Latin 'Dictator', having same meaning as in English, originating in 'dicio': 'exert authority', 'make a decision'. Modern era As late as the second half of the 19th century, the term dictator had occasional positive implications. For example, during the Hungarian Revolution of 1848, the national leader Lajos Kossuth was often referred to as dictator, without any negative connotations, by his supporters and detractors alike, although his official title was that of regent-president. When creating a provisional executive in Sicily during the Expedition of the Thousand in 1860, Giuseppe Garibaldi officially assumed the title of "Dictator" (see Dictatorship of Garibaldi). Shortly afterwards, during the 1863 January Uprising in Poland, "Dictator" was also the official title of four leaders, the first being Ludwik Mierosławski. Past that time, however, the term dictator assumed an invariably negative connotation. In popular usage, a dictatorship is often associated with brutality and oppression. As a result, it is often also used as a term of abuse against political opponents. The term has also come to be associated with megalomania. Many dictators create a cult of personality around themselves and they have also come to grant themselves increasingly grandiloquent titles and honours. For instance, Idi Amin Dada, who had been a British army lieutenant prior to Uganda's independence from Britain in October 1962, subsequently styled himself "His Excellency, President for Life, Field Marshal Al Hadji Doctor Idi Amin Dada, VC, DSO, MC, Conqueror of the British Empire in Africa in General and Uganda in Particular". In the movie The Great Dictator (1940), Charlie Chaplin satirized not only Adolf Hitler but the institution of dictatorship itself. Benevolent dictatorship A benevolent dictatorship refers to a government in which an authoritarian leader exercises absolute political power over the state but is perceived to do so with the regard for benefit of the population as a whole, standing in contrast to the decidedly malevolent stereotype of a dictator. A benevolent dictator may allow for some economic liberalization or democratic decision-making to exist, such as through public referendums or elected representatives with limited power, and often makes preparations for a transition to genuine democracy during or after their term. It might be seen as a republic a form of enlightened despotism. The label has been applied to leaders such as Ioannis Metaxas of Greece (1936–41), Josip Broz Tito of Yugoslavia (1953–80), and Lee Kuan Yew of Singapore (1959–90). Military roles The association between a dictator and the military is a common one; many dictators take great pains to emphasize their connections with the military and they often wear military uniforms. In some cases, this is perfectly legitimate; Francisco Franco was a general in the Spanish Army before he became Chief of State of Spain; Manuel Noriega was officially commander of the Panamanian Defense Forces. In other cases, the association is mere pretense. Crowd manipulation Some dictators have been masters of crowd manipulation, such as Mussolini and Hitler. Others were more prosaic speakers, such as Stalin and Franco. Typically the dictator's people seize control of all media, censor or destroy the opposition, and give strong doses of propaganda daily, often built around a cult of personality. Mussolini and Hitler used similar, modest titles referring to them as "the Leader". Mussolini used "Il Duce" and Hitler was generally referred to as "der Führer", meaning 'Leader' in German language. Franco used a similar title "El Caudillo" ("the Head", 'the chieftain') and for Stalin his adopted name became synonyms with his role as the absolute leader. For Mussolini, Hitler, and Franco, the use of modest, non-traditional titles displayed their absolute power even stronger as they did not need any, not even a historic legitimacy either. Criticism The usage of the term dictator in western media has been criticized by the left-leaning organization Fairness & Accuracy in Reporting as "Code for Government We Don't Like". According to them, leaders that would generally be considered authoritarian but are allied with the US such as Paul Biya or Nursultan Nazarbayev are rarely referred to as "dictators", while leaders of countries opposed	government in the Philippines which was headed by Emilio Aguinaldo with formally holding the title of dictator. The dictatorial government was superseded by the revolutionary government with Aguinaldo as president. Human rights abuses Over time, dictators have been known to use tactics that violate human rights. For example, under the Soviet dictator Joseph Stalin, government policy was enforced by secret police and the Gulag system of prison labour camps. Most Gulag inmates were not political prisoners, although significant numbers of political prisoners could be found in the camps at any one time. Data collected from Soviet archives gives the death toll from Gulags as 1,053,829. Other human rights abuses by the Soviet state included human experimentation, the use of psychiatry as a political weapon and the denial of freedom of religion, assembly, speech and association. Similar crimes were committed during Mao Zedong's rule over the People's Republic of China during China's Cultural Revolution, where Mao set out to purge dissidents, primarily through the use of youth groups strongly committed to his cult of personality. Some dictators have been associated with genocide on certain races or groups; the most notable and wide-reaching example is the Holocaust, Adolf Hitler's genocide of eleven million people, six million of which were Jews. Later on in Democratic Kampuchea, Pol Pot and his policies killed an estimated 1.7 million people (out of a population of 7 million) during his four-year dictatorship. As a result, Pol Pot is sometimes described as "the Hitler of Cambodia" and "a genocidal tyrant". The International Criminal Court issued an arrest warrant for Sudan's military dictator Omar al-Bashir over alleged war crimes in Darfur. See also Authoritarian personality Benevolent dictator for life Chinese Communist Party Democracy Index Dictator novel Emergency powers Greek junta List of political leaders who suspended the constitution Nazi Party Strongman (politics) Supreme Leader Totalitarianism Workers' Party of Korea References Notes A He conferred a doctorate of law on himself from Makerere University. B The Victorious Cross (VC) was a medal made to emulate the British Victoria Cross. Citations Further reading Acemoglu, Daron, and James A. Robinson. Economic Origins of Dictatorship and Democracy (2009), scholarly approach to comparative political economy excerpt Armillas-Tiseyra, Magalí. The Dictator Novel: Writers and Politics in the Global South (2019) excerpt Baehr, Peter and Melvin Richter. Dictatorship in History and Theory (2004) scholarly focus on 19c Europe. Ben-Ghiat, Ruth. Strongmen: Mussolini to the Present (2020) scholarly analysis of 13 major dictators; excerpt Brooker, Paul. Defiant Dictatorships: Communist and Middle-Eastern Dictatorships in a Democratic Age (Palgrave Macmillan, 1997). excerpt Costa Pinto, António. Latin American Dictatorships in the Era of Fascism: The Corporatist Wave (Routledge, 2019) excerpt Crowson, Nick. Facing Fascism: The Conservative Party and the European Dictators 1935-40 (Routledge, 1997), how the Conservative government in Britain dealt with them. Dávila, Jerry. Dictatorship in South America (2013), covers Brazil, Argentina, and Chile since 1945. excerpt Galván, Javier A. Latin American Dictators of the 20th Century: The Lives and Regimes of 15 Rulers (2012), brief scholarly summaries; excerpt Hamill, Hugh M. Caudillos: dictators in Spanish America (U of Oklahoma Press, 1995). Harford Vargas, Jennifer. Forms of Dictatorship: Power, Narrative, and Authoritarianism in the Latina/o Novel (Oxford
of a multi-component system, such as a series of amplifier stages, can be calculated by summing the gains in decibels of the individual components, rather than multiply the amplification factors; that is, = log(A) + log(B) + log(C). Practically, this means that, armed only with the knowledge that 1 dB is a power gain of approximately 26%, 3 dB is approximately 2× power gain, and 10 dB is 10× power gain, it is possible to determine the power ratio of a system from the gain in dB with only simple addition and multiplication. For example: A system consists of 3 amplifiers in series, with gains (ratio of power out to in) of 10 dB, 8 dB, and 7 dB respectively, for a total gain of 25 dB. Broken into combinations of 10, 3, and 1 dB, this is: 25 dB = 10 dB + 10 dB + 3 dB + 1 dB + 1 dB With an input of 1 watt, the output is approximately 1 W × 10 × 10 × 2 × 1.26 × 1.26 ≈ 317.5 W Calculated precisely, the output is 1 W × 10 ≈ 316.2 W. The approximate value has an error of only +0.4% with respect to the actual value, which is negligible given the precision of the values supplied and the accuracy of most measurement instrumentation. However, according to its critics, the decibel creates confusion, obscures reasoning, is more related to the era of slide rules than to modern digital processing, and is cumbersome and difficult to interpret. Quantities in decibels are not necessarily additive, thus being "of unacceptable form for use in dimensional analysis". Thus, units require special care in decibel operations. Take, for example, carrier-to-noise-density ratio C/N0 (in hertz), involving carrier power C (in watts) and noise power spectral density N0 (in W/Hz). Expressed in decibels, this ratio would be a subtraction (C/N0)dB = CdB - N0dB. However, the linear-scale units still simplify in the implied fraction, so that the results would be expressed in dB-Hz. Representation of addition operations According to Mitschke, "The advantage of using a logarithmic measure is that in a transmission chain, there are many elements concatenated, and each has its own gain or attenuation. To obtain the total, addition of decibel values is much more convenient than multiplication of the individual factors." However, for the same reason that humans excel at additive operation over multiplication, decibels are awkward in inherently additive operations:if two machines each individually produce a sound pressure level of, say, 90 dB at a certain point, then when both are operating together we should expect the combined sound pressure level to increase to 93 dB, but certainly not to 180 dB!; suppose that the noise from a machine is measured (including the contribution of background noise) and found to be 87 dBA but when the machine is switched off the background noise alone is measured as 83 dBA. [...] the machine noise [level (alone)] may be obtained by 'subtracting' the 83 dBA background noise from the combined level of 87 dBA; i.e., 84.8 dBA.; in order to find a representative value of the sound level in a room a number of measurements are taken at different positions within the room, and an average value is calculated. [...] Compare the logarithmic and arithmetic averages of [...] 70 dB and 90 dB: logarithmic average = 87 dB; arithmetic average = 80 dB. Addition on a logarithmic scale is called logarithmic addition, and can be defined by taking exponentials to convert to a linear scale, adding there, and then taking logarithms to return. For example, where operations on decibels are logarithmic addition/subtraction and logarithmic multiplication/division, while operations on the linear scale are the usual operations: Note that the logarithmic mean is obtained from the logarithmic sum by subtracting , since logarithmic division is linear subtraction. Fractions Attenuation constants, in topics such as optical fiber communication and radio propagation path loss, are often expressed as a fraction or ratio to distance of transmission. In this case, dB/m represents decibel per meter, dB/mi represents decibel per mile, for example. These quantities are to be manipulated obeying the rules of dimensional analysis, e.g., a 100-meter run with a 3.5 dB/km fiber yields a loss of 0.35 dB = 3.5 dB/km × 0.1 km. Uses Perception The human perception of the intensity of sound and light more nearly approximates the logarithm of intensity rather than a linear relationship (see Weber–Fechner law), making the dB scale a useful measure. Acoustics The decibel is commonly used in acoustics as a unit of sound pressure level. The reference pressure for sound in air is set at the typical threshold of perception of an average human and there are common comparisons used to illustrate different levels of sound pressure. As sound pressure is a root-power quantity, the appropriate version of the unit definition is used: where prms is the root mean square of the measured sound pressure and pref is the standard reference sound pressure of 20 micropascals in air or 1 micropascal in water. Use of the decibel in underwater acoustics leads to confusion, in part because of this difference in reference value. The human ear has a large dynamic range in sound reception. The ratio of the sound intensity that causes permanent damage during short exposure to that of the quietest sound that the ear can hear is equal to or greater than 1 trillion (1012). Such large measurement ranges are conveniently expressed in logarithmic scale: the base-10 logarithm of 1012 is 12, which is expressed as a sound pressure level of 120 dB re 20 μPa. Since the human ear is not equally sensitive to all sound frequencies, the acoustic power spectrum is modified by frequency weighting (A-weighting being the most common standard) to get the weighted acoustic power before converting to a sound level or noise level in decibels. Telephony The decibel is used in telephony and audio. Similarly to the use in acoustics, a frequency weighted power is often used. For audio noise measurements in electrical circuits, the weightings are called psophometric weightings. Electronics In electronics, the decibel is often used to express power or amplitude ratios (as for gains) in preference to arithmetic ratios or percentages. One advantage is that the total decibel gain of a series of components (such as amplifiers and attenuators) can be calculated simply by summing the decibel gains of the individual components. Similarly, in telecommunications, decibels denote signal gain or loss from a transmitter to a receiver through some medium (free space, waveguide, coaxial cable, fiber optics, etc.) using a link budget. The decibel unit can also be combined with a reference level, often indicated via a suffix, to create an absolute unit of electric power. For example, it can be combined with "m" for "milliwatt" to produce the "dBm". A power level of 0 dBm corresponds to one milliwatt, and 1 dBm is one decibel greater (about 1.259 mW). In professional audio specifications, a popular unit is the dBu. This is relative to the root mean square voltage which delivers 1 mW (0 dBm) into a 600-ohm resistor, or ≈ 0.775 VRMS. When used in a 600-ohm circuit (historically, the standard reference impedance in telephone circuits), dBu and dBm are identical. Optics In an optical link, if a known amount of optical power, in dBm (referenced to 1 mW), is launched into a fiber, and the losses, in dB (decibels), of each component (e.g., connectors, splices, and lengths of fiber) are known, the overall link loss may be quickly calculated by addition and subtraction of decibel quantities. In spectrometry and optics, the blocking unit used to measure optical density is equivalent to −1 B. Video and digital imaging In connection with video and digital image sensors, decibels generally represent ratios of video voltages or digitized light intensities, using 20 log of the ratio, even when the represented intensity (optical power) is directly proportional to the voltage generated by the sensor, not to its square, as in a CCD imager where response voltage is linear in intensity. Thus, a camera signal-to-noise ratio or dynamic range quoted as 40 dB represents a ratio of 100:1 between optical signal intensity and optical-equivalent dark-noise intensity, not a 10,000:1 intensity (power) ratio as 40 dB might suggest. Sometimes the 20 log ratio definition is applied to electron counts or photon counts directly, which are proportional to sensor signal amplitude without the need to consider whether the voltage response to intensity is linear. However, as mentioned above, the 10 log intensity convention prevails more generally in physical optics, including fiber optics, so the terminology can become murky between the conventions of digital photographic technology and physics. Most commonly, quantities called "dynamic range" or "signal-to-noise" (of the camera) would be specified in 20 log dB, but in related contexts (e.g. attenuation, gain, intensifier SNR, or rejection ratio) the term should be interpreted cautiously, as confusion of the two units can result in very large misunderstandings of the value. Photographers typically use an alternative base-2 log unit, the stop, to describe light intensity ratios or dynamic range. Suffixes and reference values Suffixes are commonly attached to the basic dB unit in order to indicate the reference value by which the ratio is calculated. For example, dBm indicates power measurement relative to 1 milliwatt. In cases where the unit value of the reference is stated, the decibel value is known as "absolute". If the unit value of the reference is not explicitly stated, as in the dB gain of an amplifier, then the decibel value is considered relative. This form of attaching suffixes to dB is widespread in practice, albeit being against the rules promulgated by standards bodies (ISO and IEC), given the "unacceptability of attaching information to units" and the "unacceptability of mixing information with units". The IEC 60027-3 standard recommends the following format: Lx (re xref) or as Lx/xref, where x is the quantity symbol and xref is the value of the reference quantity, e.g., LE (re 1 μV/m) = 20 dB or LE/(1 μV/m)= 20 dB for the electric field strength E relative to 1 μV/m reference value. If the measurement result 20 dB is presented separately, it can be specified using the information in parentheses, which is then part of the surrounding text and not a part of the unit: 20 dB (re: 1 μV/m) or 20 dB (1 μV/m). Outside of documents adhering to SI units, the practice is very common as illustrated by the following examples. There is no general rule, with various discipline-specific practices. Sometimes the suffix is a unit symbol ("W","K","m"), sometimes it is a transliteration of a unit symbol ("uV" instead of μV for microvolt), sometimes it is an acronym for the unit's name ("sm" for square meter, "m" for milliwatt), other times it is a mnemonic for the type of quantity being calculated ("i" for antenna gain with respect to an isotropic antenna, "λ" for anything normalized by the EM wavelength), or otherwise a general attribute or identifier about the nature of the quantity ("A" for A-weighted sound pressure level). The suffix is often connected with a hyphen, as in "dBHz", or with a space, as in "dB HL", or enclosed in parentheses, as in "dB(sm)", or with no intervening character, as in "dBm" (which is non-compliant with international standards). Voltage Since the decibel is defined with respect to power, not amplitude, conversions of voltage ratios to decibels must square the amplitude, or use the factor of 20 instead of 10, as discussed above. dBV dB(VRMS) – voltage relative to 1 volt, regardless of impedance. This is used to measure microphone sensitivity, and also to specify the consumer line-level of , in order to reduce manufacturing costs relative to equipment using a line-level signal. dBu or dBv RMS voltage relative to (i.e. the voltage that would dissipate 1 mW into a 600 Ω load). An RMS voltage of 1 V therefore corresponds to Originally dBv, it was changed to dBu to avoid confusion with dBV. The "v" comes from "volt", while "u" comes from the volume unit used in the VU meter.dBu can be used as a measure of voltage, regardless of impedance, but is derived from a 600 Ω load dissipating 0 dBm (1 mW). The reference voltage comes from the computation where is the resistance and is the power. In professional audio, equipment may be calibrated to indicate a "0" on the VU meters some finite time after a signal has been applied at an amplitude of . Consumer equipment typically uses a lower "nominal" signal level of . Therefore, many devices offer dual voltage operation (with different gain or "trim" settings) for interoperability reasons. A switch or adjustment that covers at least the range between and is common in professional equipment. dBm0s Defined by Recommendation ITU-R V.574.; dBmV: dB(mVRMS) – voltage relative to 1 millivolt across 75 Ω. Widely used in cable television networks, where the nominal strength of a single TV signal at the receiver terminals is about 0 dBmV. Cable TV uses 75 Ω coaxial cable, so 0 dBmV corresponds to −78.75 dBW (−48.75 dBm) or approximately 13 nW. dBμV or dBuV dB(μVRMS) – voltage relative to 1 microvolt. Widely used in television and aerial amplifier specifications. 60 dBμV = 0 dBmV. Acoustics Probably the most common usage of "decibels" in reference to sound level is dB SPL, sound pressure level referenced to the nominal threshold of human hearing: The measures of pressure (a root-power quantity) use the factor of 20, and the measures of power (e.g. dB SIL and dB SWL) use the factor of 10. dB SPL dB SPL (sound pressure level) – for sound in air and other gases, relative to 20 micropascals (μPa), or , approximately the quietest sound a human can hear. For sound in water and other liquids, a reference pressure of 1 μPa is used. An RMS sound pressure of one pascal corresponds to a level of 94 dB SPL. dB SIL dB sound intensity level – relative to 10−12 W/m2, which is roughly the threshold of human hearing in air. dB SWL dB sound power level – relative to 10−12 W. dBA, dBB, and dBC These symbols are often used to denote the use of different weighting filters, used to approximate the human ear's response to sound, although the measurement is still in dB (SPL). These measurements usually refer to noise and its effects on humans and other animals, and they are widely used in industry while discussing noise control issues, regulations	is much more convenient than multiplication of the individual factors." However, for the same reason that humans excel at additive operation over multiplication, decibels are awkward in inherently additive operations:if two machines each individually produce a sound pressure level of, say, 90 dB at a certain point, then when both are operating together we should expect the combined sound pressure level to increase to 93 dB, but certainly not to 180 dB!; suppose that the noise from a machine is measured (including the contribution of background noise) and found to be 87 dBA but when the machine is switched off the background noise alone is measured as 83 dBA. [...] the machine noise [level (alone)] may be obtained by 'subtracting' the 83 dBA background noise from the combined level of 87 dBA; i.e., 84.8 dBA.; in order to find a representative value of the sound level in a room a number of measurements are taken at different positions within the room, and an average value is calculated. [...] Compare the logarithmic and arithmetic averages of [...] 70 dB and 90 dB: logarithmic average = 87 dB; arithmetic average = 80 dB. Addition on a logarithmic scale is called logarithmic addition, and can be defined by taking exponentials to convert to a linear scale, adding there, and then taking logarithms to return. For example, where operations on decibels are logarithmic addition/subtraction and logarithmic multiplication/division, while operations on the linear scale are the usual operations: Note that the logarithmic mean is obtained from the logarithmic sum by subtracting , since logarithmic division is linear subtraction. Fractions Attenuation constants, in topics such as optical fiber communication and radio propagation path loss, are often expressed as a fraction or ratio to distance of transmission. In this case, dB/m represents decibel per meter, dB/mi represents decibel per mile, for example. These quantities are to be manipulated obeying the rules of dimensional analysis, e.g., a 100-meter run with a 3.5 dB/km fiber yields a loss of 0.35 dB = 3.5 dB/km × 0.1 km. Uses Perception The human perception of the intensity of sound and light more nearly approximates the logarithm of intensity rather than a linear relationship (see Weber–Fechner law), making the dB scale a useful measure. Acoustics The decibel is commonly used in acoustics as a unit of sound pressure level. The reference pressure for sound in air is set at the typical threshold of perception of an average human and there are common comparisons used to illustrate different levels of sound pressure. As sound pressure is a root-power quantity, the appropriate version of the unit definition is used: where prms is the root mean square of the measured sound pressure and pref is the standard reference sound pressure of 20 micropascals in air or 1 micropascal in water. Use of the decibel in underwater acoustics leads to confusion, in part because of this difference in reference value. The human ear has a large dynamic range in sound reception. The ratio of the sound intensity that causes permanent damage during short exposure to that of the quietest sound that the ear can hear is equal to or greater than 1 trillion (1012). Such large measurement ranges are conveniently expressed in logarithmic scale: the base-10 logarithm of 1012 is 12, which is expressed as a sound pressure level of 120 dB re 20 μPa. Since the human ear is not equally sensitive to all sound frequencies, the acoustic power spectrum is modified by frequency weighting (A-weighting being the most common standard) to get the weighted acoustic power before converting to a sound level or noise level in decibels. Telephony The decibel is used in telephony and audio. Similarly to the use in acoustics, a frequency weighted power is often used. For audio noise measurements in electrical circuits, the weightings are called psophometric weightings. Electronics In electronics, the decibel is often used to express power or amplitude ratios (as for gains) in preference to arithmetic ratios or percentages. One advantage is that the total decibel gain of a series of components (such as amplifiers and attenuators) can be calculated simply by summing the decibel gains of the individual components. Similarly, in telecommunications, decibels denote signal gain or loss from a transmitter to a receiver through some medium (free space, waveguide, coaxial cable, fiber optics, etc.) using a link budget. The decibel unit can also be combined with a reference level, often indicated via a suffix, to create an absolute unit of electric power. For example, it can be combined with "m" for "milliwatt" to produce the "dBm". A power level of 0 dBm corresponds to one milliwatt, and 1 dBm is one decibel greater (about 1.259 mW). In professional audio specifications, a popular unit is the dBu. This is relative to the root mean square voltage which delivers 1 mW (0 dBm) into a 600-ohm resistor, or ≈ 0.775 VRMS. When used in a 600-ohm circuit (historically, the standard reference impedance in telephone circuits), dBu and dBm are identical. Optics In an optical link, if a known amount of optical power, in dBm (referenced to 1 mW), is launched into a fiber, and the losses, in dB (decibels), of each component (e.g., connectors, splices, and lengths of fiber) are known, the overall link loss may be quickly calculated by addition and subtraction of decibel quantities. In spectrometry and optics, the blocking unit used to measure optical density is equivalent to −1 B. Video and digital imaging In connection with video and digital image sensors, decibels generally represent ratios of video voltages or digitized light intensities, using 20 log of the ratio, even when the represented intensity (optical power) is directly proportional to the voltage generated by the sensor, not to its square, as in a CCD imager where response voltage is linear in intensity. Thus, a camera signal-to-noise ratio or dynamic range quoted as 40 dB represents a ratio of 100:1 between optical signal intensity and optical-equivalent dark-noise intensity, not a 10,000:1 intensity (power) ratio as 40 dB might suggest. Sometimes the 20 log ratio definition is applied to electron counts or photon counts directly, which are proportional to sensor signal amplitude without the need to consider whether the voltage response to intensity is linear. However, as mentioned above, the 10 log intensity convention prevails more generally in physical optics, including fiber optics, so the terminology can become murky between the conventions of digital photographic technology and physics. Most commonly, quantities called "dynamic range" or "signal-to-noise" (of the camera) would be specified in 20 log dB, but in related contexts (e.g. attenuation, gain, intensifier SNR, or rejection ratio) the term should be interpreted cautiously, as confusion of the two units can result in very large misunderstandings of the value. Photographers typically use an alternative base-2 log unit, the stop, to describe light intensity ratios or dynamic range. Suffixes and reference values Suffixes are commonly attached to the basic dB unit in order to indicate the reference value by which the ratio is calculated. For example, dBm indicates power measurement relative to 1 milliwatt. In cases where the unit value of the reference is stated, the decibel value is known as "absolute". If the unit value of the reference is not explicitly stated, as in the dB gain of an amplifier, then the decibel value is considered relative. This form of attaching suffixes to dB is widespread in practice, albeit being against the rules promulgated by standards bodies (ISO and IEC), given the "unacceptability of attaching information to units" and the "unacceptability of mixing information with units". The IEC 60027-3 standard recommends the following format: Lx (re xref) or as Lx/xref, where x is the quantity symbol and xref is the value of the reference quantity, e.g., LE (re 1 μV/m) = 20 dB or LE/(1 μV/m)= 20 dB for the electric field strength E relative to 1 μV/m reference value. If the measurement result 20 dB is presented separately, it can be specified using the information in parentheses, which is then part of the surrounding text and not a part of the unit: 20 dB (re: 1 μV/m) or 20 dB (1 μV/m). Outside of documents adhering to SI units, the practice is very common as illustrated by the following examples. There is no general rule, with various discipline-specific practices. Sometimes the suffix is a unit symbol ("W","K","m"), sometimes it is a transliteration of a unit symbol ("uV" instead of μV for microvolt), sometimes it is an acronym for the unit's name ("sm" for square meter, "m" for milliwatt), other times it is a mnemonic for the type of quantity being calculated ("i" for antenna gain with respect to an isotropic antenna, "λ" for anything normalized by the EM wavelength), or otherwise a general attribute or identifier about the nature of the quantity ("A" for A-weighted sound pressure level). The suffix is often connected with a hyphen, as in "dBHz", or with a space, as in "dB HL", or enclosed in parentheses, as in "dB(sm)", or with no intervening character, as in "dBm" (which is non-compliant with international standards). Voltage Since the decibel is defined with respect to power, not amplitude, conversions of voltage ratios to decibels must square the amplitude, or use the factor of 20 instead of 10, as discussed above. dBV dB(VRMS) – voltage relative to 1 volt, regardless of impedance. This is used to measure microphone sensitivity, and also to specify the consumer line-level of , in order to reduce manufacturing costs relative to equipment using a line-level signal. dBu or dBv RMS voltage relative to (i.e. the voltage that would dissipate 1 mW into a 600 Ω load). An RMS voltage of 1 V therefore corresponds to Originally dBv, it was changed to dBu to avoid confusion with dBV. The "v" comes from "volt", while "u" comes from the volume unit used in the VU meter.dBu can be used as a measure of voltage, regardless of impedance, but is derived from a 600 Ω load dissipating 0 dBm (1 mW). The reference voltage comes from the computation where is the resistance and is the power. In professional audio, equipment may be calibrated to indicate a "0" on the VU meters some finite time after a signal has been applied at an amplitude of . Consumer equipment typically uses a lower "nominal" signal level of . Therefore, many devices offer dual voltage operation (with different gain or "trim" settings) for interoperability reasons. A switch or adjustment that covers at least the range between and is common in professional equipment. dBm0s Defined by Recommendation ITU-R V.574.; dBmV: dB(mVRMS) – voltage relative to 1 millivolt across 75 Ω. Widely used in cable television networks, where the nominal strength of a single TV signal at the receiver terminals is about 0 dBmV. Cable TV uses 75 Ω coaxial cable, so 0 dBmV corresponds to −78.75 dBW (−48.75 dBm) or approximately 13 nW. dBμV or dBuV dB(μVRMS) – voltage relative to 1 microvolt. Widely used in television and aerial amplifier specifications. 60 dBμV = 0 dBmV. Acoustics Probably the most common usage of "decibels" in reference to sound level is dB SPL, sound pressure level referenced to the nominal threshold of human hearing: The measures of pressure (a root-power quantity) use the factor of 20, and the measures of power (e.g. dB SIL and dB SWL) use the factor of 10. dB SPL dB SPL (sound pressure level) – for sound in air and other gases, relative to 20 micropascals (μPa), or , approximately the quietest sound a human can hear. For sound in water and other liquids, a reference pressure of 1 μPa is used. An RMS sound pressure of one pascal corresponds to a level of 94 dB SPL. dB SIL dB sound intensity level – relative to 10−12 W/m2, which is roughly the threshold of human hearing in air. dB SWL dB sound power level – relative to 10−12 W. dBA, dBB, and dBC These symbols are often used to denote the use of different weighting filters, used to approximate the human ear's response to sound, although the measurement is still in dB (SPL). These measurements usually refer to noise and its effects on humans and other animals, and they are widely used in industry while discussing noise control issues, regulations and environmental standards. Other variations that may be seen are dBA or dB(A). According to standards from the International Electro-technical Committee (IEC 61672-2013) and the American National Standards Institute, ANSI S1.4, the preferred usage is to write LA = x dB. Nevertheless, the units dBA and dB(A) are still commonly used as a shorthand for Aweighted measurements. Compare dBc, used in telecommunications. dB HL dB hearing level is used in audiograms as a measure of hearing loss. The reference level varies with frequency according to a minimum audibility curve as defined in ANSI and other standards, such that the resulting audiogram shows deviation from what is regarded as 'normal' hearing. dB Q sometimes used to denote weighted noise level, commonly using the ITU-R 468 noise weighting dBpp relative to the peak to peak sound pressure. dBG Gweighted spectrum Audio electronics See also dBV and dBu above. dBm dB(mW) – power relative to 1 milliwatt. In audio and telephony, dBm is typically referenced relative to a 600 Ω impedance, which corresponds to a voltage level of 0.775 volts or 775 millivolts. dBm0 Power in dBm (described above) measured at a zero transmission level point. dBFS dB(full scale) – the amplitude of a signal compared with the maximum which a device can handle before clipping occurs. Full-scale may be defined as the power level of a full-scale sinusoid or alternatively a full-scale square wave. A signal measured with reference to a full-scale sine-wave appears 3 dB weaker when referenced to a full-scale square wave, thus: 0 dBFS(fullscale sine wave) = −3 dBFS(fullscale square wave). dBVU dB volume unit dBTP dB(true peak) – peak amplitude of a signal compared with the maximum which a device can handle before clipping occurs. In digital systems, 0 dBTP would equal the highest level (number) the processor is capable of representing. Measured values are always negative or zero, since they are less than or equal to full-scale. Radar dBZ dB(Z) – decibel relative to Z = 1 mm6⋅m−3: energy of reflectivity (weather radar), related to the amount of transmitted power returned to the radar receiver. Values above 20 dBZ usually indicate falling precipitation. dBsm dB(m2) – decibel relative to one square meter: measure of the radar cross section (RCS) of a target. The power reflected by the target is proportional to its RCS. "Stealth" aircraft and insects have negative RCS measured in dBsm, large flat plates or non-stealthy aircraft have positive values. Radio power, energy, and field strength dBc relative to carrier – in telecommunications, this indicates the relative levels of noise or sideband power, compared with the carrier power. Compare dBC, used in acoustics. dBpp relative to the maximum value of the peak power. dBJ energy relative to 1 joule. 1 joule = 1 watt second = 1 watt per hertz, so power spectral density can be expressed in dBJ. dBm dB(mW) – power relative to 1 milliwatt. In the radio field, dBm is usually referenced to a 50 Ω load, with the resultant voltage being 0.224 volts. dBμV/m, dBuV/m, or dBμ dB(μV/m) – electric field strength relative to 1 microvolt per meter. The unit is often used to specify the signal strength of a television broadcast at a receiving site (the signal measured at the antenna output is reported in dBμV). dBf dB(fW) – power relative to 1 femtowatt. dBW dB(W) – power relative to 1 watt. dBk dB(kW) – power relative to 1 kilowatt. dBe dB electrical. dBo dB optical. A change of 1 dBo in optical power can result in a change of up to 2 dBe in electrical signal power in a system that is thermal noise limited. Antenna measurements dBi dB(isotropic) – the forward gain of an antenna compared with the hypothetical isotropic antenna, which uniformly distributes energy in all directions. Linear polarization of the EM field is assumed unless noted otherwise. dBd dB(dipole) – the forward gain of an antenna compared with a half-wave dipole antenna. 0 dBd = 2.15 dBi dBiC dB(isotropic circular) – the forward gain of an antenna compared to a circularly polarized isotropic antenna. There is no fixed conversion rule between dBiC and dBi, as it depends on the receiving antenna and the field polarization. dBq dB(quarterwave) – the forward gain of an antenna compared to a quarter wavelength whip. Rarely used, except in some marketing material. 0 dBq = −0.85 dBi dBsm dB(m2) – decibel relative to one square meter: measure of the antenna effective area. dBm−1 dB(m−1) – decibel relative to reciprocal of meter: measure of the antenna factor. Other measurements dBHz dB(Hz) – bandwidth relative to one hertz. E.g., 20 dBHz corresponds to a bandwidth of 100 Hz. Commonly used in link budget calculations. Also used in carrier-to-noise-density ratio (not to be confused with carrier-to-noise ratio, in dB). dBov or dBO dB(overload) – the amplitude of a signal (usually audio) compared with the maximum which a device can handle before clipping occurs. Similar to dBFS, but also applicable to analog systems. According to ITU-T Rec. G.100.1 the level in dBov of a digital system is defined as: , with the maximum signal power , for a rectangular signal with the maximum amplitude . The level of a tone with a digital amplitude (peak value) of is therefore . dBr dB(relative) – simply a relative difference from something else, which is made apparent in context. The difference of a filter's response to nominal levels, for instance. dBrn dB above reference noise. See also dBrnC dBrnC dBrnC represents an audio level measurement, typically in a telephone circuit, relative to a -90 dBm reference level, with the measurement of this level frequency-weighted by a standard C-message weighting filter. The C-message weighting filter was chiefly used in North America. The Psophometric filter is used for this purpose on international circuits. See Psophometric weighting to see a comparison of frequency response curves for the C-message weighting and Psophometric weighting filters. dBKdB(K) – decibels relative to 1 K; used to express noise temperature. dB/K dB(K−1) – decibels relative to 1 K−1. — not decibels per kelvin: Used for the G/T factor, a figure of merit utilized in satellite communications, relating the antenna gain G to the receiver system noise equivalent temperature T. List of suffixes in alphabetical order Unpunctuated suffixes dBA see dB(A). dBa see dBrn adjusted. dBB see dB(B). dBc relative to carrier – in telecommunications, this indicates the relative levels of noise or sideband power, compared with the carrier power. dBC see dB(C). dBD see dB(D). dBd dB(dipole) – the forward gain of an antenna compared with a half-wave dipole antenna. 0 dBd = 2.15 dBi dBe dB electrical. dBf dB(fW) – power relative to 1 femtowatt. dBFS dB(full scale) – the amplitude of a signal compared with the maximum which a device can handle before clipping occurs. Full-scale may be defined as the power level of a full-scale sinusoid or
by Wallace who was a strict selectionist. Romanes' definition of Darwinism conformed directly with Darwin's views and was contrasted with Wallace's definition of the term. Millennial usage The term Darwinism is often used in the United States by promoters of creationism, notably by leading members of the intelligent design movement, as an epithet to attack evolution as though it were an ideology (an "ism") of philosophical naturalism, or atheism. For example, in 1993, UC Berkeley law professor and author Phillip E. Johnson made this accusation of atheism with reference to Charles Hodge's 1874 book What Is Darwinism?. However, unlike Johnson, Hodge confined the term to exclude those like American botanist Asa Gray who combined Christian faith with support for Darwin's natural selection theory, before answering the question posed in the book's title by concluding: "It is Atheism." Creationists use pejoratively the term Darwinism to imply that the theory has been held as true only by Darwin and a core group of his followers, whom they cast as dogmatic and inflexible in their belief. In the 2008 documentary film Expelled: No Intelligence Allowed, which promotes intelligent design (ID), American writer and actor Ben Stein refers to scientists as Darwinists. Reviewing the film for Scientific American, John Rennie says "The term is a curious throwback, because in modern biology almost no one relies solely on Darwin's original ideas... Yet the choice of terminology isn't random: Ben Stein wants you to stop thinking of evolution as an actual science supported by verifiable facts and logical arguments and to start thinking of it as a dogmatic, atheistic ideology akin to Marxism." However, Darwinism is also used neutrally within the scientific community to distinguish the modern evolutionary synthesis, which is sometimes called "neo-Darwinism", from those first proposed by Darwin. Darwinism also is used neutrally by historians to differentiate his theory from other evolutionary theories current around the same period. For example, Darwinism may refer to Darwin's proposed mechanism of natural selection, in comparison to more recent mechanisms such as genetic drift and gene flow. It may also refer specifically to the role of Charles Darwin as opposed to others in the history of evolutionary thought—particularly contrasting Darwin's results with those of earlier theories such as Lamarckism or later ones such as the modern evolutionary synthesis. In political discussions in the United States, the term is mostly used by its enemies. "It's a rhetorical device to make evolution seem like a kind of faith, like 'Maoism,'" says Harvard University biologist E. O. Wilson. He adds, "Scientists don't call it 'Darwinism'." In the United Kingdom the term often retains its positive sense as a reference to natural selection, and for example British ethologist and evolutionary biologist Richard Dawkins wrote in his collection of essays A Devil's Chaplain, published in 2003, that as a scientist he is a Darwinist. In his 1995 book Darwinian Fairytales, Australian philosopher David Stove used the term "Darwinism" in a different sense than the above examples. Describing himself as non-religious and as accepting the concept of natural selection as a well-established fact, Stove nonetheless attacked what he described as flawed concepts proposed by some "Ultra-Darwinists." Stove alleged that by using weak or false ad hoc reasoning, these Ultra-Darwinists used evolutionary concepts to offer explanations that were not valid: for example, Stove suggested that the sociobiological explanation of altruism as an evolutionary feature was presented in such a way that the argument was effectively immune to any criticism. English philosopher Simon Blackburn wrote a rejoinder to Stove, though a subsequent essay by Stove's protégé James Franklin suggested that Blackburn's response actually "confirms Stove's central thesis that Darwinism can 'explain' anything." Esoteric usage In evolutionary aesthetics theory, there is evidence that perceptions of beauty are determined by natural selection and therefore Darwinian; that things, aspects of people and landscapes considered beautiful are typically found in situations likely to give enhanced survival of the perceiving human's genes. See also Darwin Awards Evidence of common descent History of evolutionary thought Modern evolutionary synthesis Neural Darwinism Pangenesis—Charles Darwin's hypothetical mechanism for heredity Speciation Universal Darwinism References Sources	modern evolutionary theory. For example, Darwin was unfamiliar with the work of the Moravian scientist and Augustinian friar Gregor Mendel, and as a result had only a vague and inaccurate understanding of heredity. He naturally had no inkling of later theoretical developments and, like Mendel himself, knew nothing of genetic drift, for example. In the United States, creationists often use the term "Darwinism" as a pejorative term in reference to beliefs such as scientific materialism, but in the United Kingdom the term has no negative connotations, being freely used as a shorthand for the body of theory dealing with evolution, and in particular, with evolution by natural selection. Huxley and Kropotkin Huxley, upon first reading Darwin's theory in 1858, responded, "How extremely stupid not to have thought of that!" While the term Darwinism had been used previously to refer to the work of Erasmus Darwin in the late 18th century, the term as understood today was introduced when Charles Darwin's 1859 book On the Origin of Species was reviewed by Thomas Henry Huxley in the April 1860 issue of the Westminster Review. Having hailed the book as "a veritable Whitworth gun in the armoury of liberalism" promoting scientific naturalism over theology, and praising the usefulness of Darwin's ideas while expressing professional reservations about Darwin's gradualism and doubting if it could be proved that natural selection could form new species, Huxley compared Darwin's achievement to that of Nicolaus Copernicus in explaining planetary motion: These are the basic tenets of evolution by natural selection as defined by Darwin: More individuals are produced each generation than can survive. Phenotypic variation exists among individuals and the variation is heritable. Those individuals with heritable traits better suited to the environment will survive. When reproductive isolation occurs new species will form. Another important evolutionary theorist of the same period was the Russian geographer and prominent anarchist Pyotr Kropotkin who, in his book Mutual Aid: A Factor of Evolution (1902), advocated a conception of Darwinism counter to that of Huxley. His conception was centred around what he saw as the widespread use of co-operation as a survival mechanism in human societies and animals. He used biological and sociological arguments in an attempt to show that the main factor in facilitating evolution is cooperation between individuals in free-associated societies and groups. This was in order to counteract the conception of fierce competition as the core of evolution, which provided a rationalization for the dominant political, economic and social theories of the time; and the prevalent interpretations of Darwinism, such as those by Huxley, who is targeted as an opponent by Kropotkin. Kropotkin's conception of Darwinism could be summed up by the following quote: Other 19th-century usage "Darwinism" soon came to stand for an entire range of evolutionary (and often revolutionary) philosophies about both biology and society. One of the more prominent approaches, summed in the 1864 phrase "survival of the fittest" by Herbert Spencer, later became emblematic of Darwinism even though Spencer's own understanding of evolution (as expressed in 1857) was more similar to that of Jean-Baptiste Lamarck than to that of Darwin, and predated the publication of Darwin's theory in 1859. What is now called "Social Darwinism" was, in its day, synonymous with "Darwinism"—the application of Darwinian principles of "struggle" to society, usually in support of anti-philanthropic political agenda. Another interpretation, one notably favoured by Darwin's half-cousin Francis Galton, was that "Darwinism" implied that because natural selection was apparently no longer working on "civilized" people, it was possible for "inferior" strains of people (who would normally be filtered out of the gene pool) to overwhelm the "superior" strains, and voluntary corrective measures would be desirable—the foundation of eugenics. In Darwin's day there was no rigid definition of the term "Darwinism", and it was used by opponents and proponents of Darwin's biological theory alike to mean whatever they wanted it to in a larger context. The ideas had international influence, and Ernst Haeckel developed what was known as Darwinismus in Germany, although, like Spencer's "evolution", Haeckel's "Darwinism" had only a rough resemblance to the theory of Charles Darwin, and was not centred on natural selection. In 1886, Alfred Russel Wallace went on a lecture tour across the United States, starting in New York and going via Boston, Washington, Kansas, Iowa and Nebraska to California, lecturing on what he called "Darwinism" without any problems. In his book Darwinism (1889), Wallace had used the term pure-Darwinism which proposed a "greater efficacy" for natural selection. George Romanes dubbed this view as "Wallaceism", noting that in contrast to Darwin, this position was advocating a "pure theory of natural selection to the exclusion of any supplementary theory." Taking influence from Darwin, Romanes was a proponent of both natural selection and the inheritance of acquired characteristics. The latter was denied by Wallace who was a strict selectionist. Romanes' definition of Darwinism conformed directly with Darwin's views and was contrasted with Wallace's definition of the term. Millennial usage The term Darwinism is often used in the United States by promoters of creationism, notably by leading members of the intelligent design movement, as an epithet to attack evolution as though it were an ideology (an "ism") of philosophical naturalism, or atheism. For example, in 1993, UC Berkeley law professor and author Phillip E. Johnson made this accusation of atheism with reference to Charles Hodge's 1874 book What Is Darwinism?. However, unlike Johnson, Hodge confined the term to exclude those like American botanist Asa Gray who combined Christian faith
2006, Shōgakukan published a series of five manga volumes under the title Doraemon Plus (Doraemon+), featuring short stories which did not appear in the forty-five original volumes; a sixth volume, the first volume in eight years, was published on December 1, 2014. Additionally, 119 unpublished stories were compiled into six colored-manga volumes under the title Doraemon Kara Sakuhin-shu , published from July 17, 1999 to September 2, 2006. Between July 24, 2009 and September 25, 2012, Shogakukan published a master works collection consisting of twenty volumes with all 1,345 stories written by Fujio. In December 2019, on the 50th anniversary of Doraemon, a "Volume 0" was published by Shogakukan featuring six different versions of Doraemon's first appearance. There have been two series of bilingual, Japanese and English, volumes of the manga by SHOGAKUKAN ENGLISH COMICS under the title Doraemon: Gadget Cat from the Future, and two audio versions. The first series has ten volumes and the second one has six. In addition, 21st Century Publishing House released bilingual English-Chinese versions in Mainland China, and Chingwin Publishing Group released bilingual English-Chinese versions in Taiwan. In July 2013, Fujiko F. Fujio Pro announced that they would be collaborating with ebook publisher Voyager Japan and localization company AltJapan Co., Ltd. to release an English-language version of the manga in full color digitally via the Amazon Kindle platform in North America. Shogakukan released the first volume in November 2013; as of 2016, a total of 200 volumes have been published. This English version incorporates a variety of changes to character names; Nobita is "Noby", Shizuka is "Sue", Suneo is "Sneech", and Gian is "Big G", while dorayaki is "Yummy Bun/Fudgy Pudgy Pie". Also, as of 2016, four volumes of the manga have been published in English in print by Shogakukan Asia. Shogakukan started digital distribution of all forty-five original volumes throughout Japan from July 16, 2015. Anime The first attempt of a Doraemon animated series was in 1973, by Nippon Television. After a January 1973 pilot named Doraemon Mirai Kara Yattekuru , twenty-six episodes, each with two segments, were broadcast on Nippon TV from April 1 to September 30 of the same year. The series was directed by Mitsuo Kaminashi with voice cast from Aoni Production; the character Doraemon was voiced by Kōsei Tomita, then later by Masako Nozawa. Later in the series, the animation studio, Nippon TeleMovie Productions, went bankrupt, and the masters were sold off or destroyed. The series was re-aired on Nippon TV and several local stations until 1979, when Shogakukan requested Toyama Television to cease broadcasting. Some of the segments were found in the archives of IMAGICA in 1995, and some others were recovered by Jun Masami in 2003. As of 2013, 21 of 52 segments have known to survive, two of which without audio. Doraemon remained fairly exclusive in manga form until 1979 when a newly formed animation studio, Shin-Ei Animation (now owned by TV Asahi) produced an animated second attempt of Doraemon. The series, directed by Tsutomu Shibayama, aired on TV Asahi from April 2, 1979 to March 18, 2005. Eiichi Nakamura served as director of photography and character designer, while Shunsuke Kikuchi was the composer. Nobuyo Ōyama voiced Doraemon in the series; because of this, in Asia, this version is sometimes referred to as the Ōyama Edition. In total, 1,787 episodes were produced and released in VHS and DVD by Toho. Celebrating the anniversary of the franchise, a third Doraemon animated series, also produced by Shin-Ei Animation, began airing on TV Asahi on April 15, 2005, with new voice actors and staff, and updated character designs. The third series is sometimes referred to in Asia as the Mizuta Edition, as a tribute for the voice actress for Doraemon, Wasabi Mizuta. It was released in DVD on February 10, 2006 under the title New TV-ban Doraemon with Shogakukan Video banner. In May 2014, TV Asahi Corporation announced an agreement with The Walt Disney Company to bring the 2005 series to the Disney XD television channel in the United States beginning in the summer of that year. Besides using the name changes that were used in AltJapan's English adaptation of the original manga, other changes and edits have also been made to make the show more relatable to an American audience, such as Japanese text being replaced with English text on certain objects like signs and graded papers, items such as yen notes being replaced by US dollar bills, and the setting being changed from Japan to the United States. Initial response to the edited dub was positive. The Disney adaptation began broadcast in Japan on Disney Channel from February 1, 2016. The broadcast offered the choice of the English voice track or a newly recorded Japanese track by the Japanese cast of the 2005 series. In addition, the anime has been aired in over sixty countries worldwide. It premiered in Thailand in 1982, the Philippines in 1999, India in 2005, and Vietnam in 2010. Other Asian countries that broadcast the series include China, Hong Kong, Singapore, Taiwan, Malaysia, Indonesia, and South Korea. The series is licensed in EMEA regions by LUK International; it premiered in Spain in 1993 and France in 2003. It has also been distributed in South American countries, including Brazil, Colombia, and Chile. In 2017, POPS Worldwide, a Vietnamese multimedia company, collaborated with TV Asahi to release the anime series on YouTube and other digital platforms. Feature films As of 2020, there have been forty annual feature-length animated films produced by Shin-Ei Animation and released by Toho, the most recent of which is Doraemon: Nobita's New Dinosaur, which premiered in Japan on August 7, 2020. The first twenty-five films are based on the 1979 anime, while the rest are based on the 2005 anime. Unlike the anime and manga series, the films are more action-adventure oriented, taking the familiar characters of Doraemon and placing them in a variety of exotic and perilous settings. A 3D computer animated film, Stand by Me Doraemon, debuted in Japan on August 8, 2014. Directed by Takashi Yamazaki and Ryūichi Yagi, it combines elements from the short stories of the manga series: "All the Way from the Country of the Future", "Imprinting Egg", "Goodbye, Shizuka-chan", "Romance in Snowy Mountain", "Nobita's the Night Before a Wedding", and "Goodbye, Doraemon ..." into a new complete story, from the first time Doraemon came to Nobita's house to Doraemon bidding farewell to Nobita. The film was a box office success, grossing $183.4 million worldwide. A sequel, Stand by Me Doraemon 2, also directed by Yamazaki and Yagi, was released on November 20, 2020. Short films, OVA and crossover Several Doraemon short films were produced and released between 1989 and 2004. These include 2112: The Birth of Doraemon, a film about the life of Doraemon from birth before coming to Nobita; Doraemon: Nobita's the Night Before a Wedding, a film about the events related to the marriage of Nobita and Shizuka; The Day When I Was Born and Doraemon: A Grandmother's Recollections, the films about the relationship between Nobita and his parents along with his grandmother. Other short films focus on Dorami and the Doraemons. In 1981, Toho released What Am I for Momotaro, a film about Momotarō, the hero of Japanese folklore. In 1994, an educational OVA was made, titled Doraemon: Nobita to Mirai Note , where the main characters express the hope for a better Earth. The OVA was released in DVD along with the 13th issue of Fujiko F. Fujio Wonderland magazine in September 2004. A crossover episode of Doraemon with AIBOU: Tokyo Detective Duo aired on TV Asahi on November 9, 2018. Music The soundtrack of the 1973 anime series was composed by Nobuyoshi Koshibe, who also arranged the opening theme song and the ending theme song , both performed by Harumi Naitō. For the 1979 anime, Shunsuke Kikuchi was the composer, who arranged ; it had been performed by numerous singers, including Kumiko Ōsugi and Satoko Yamano. When the anime got a reboot in 2005, Kan Sawada was the composer of the series. There are four other opening themes, including an instrumental version of "Doraemon no Uta" performed by Twelve Girls Band; "Hagushichao" performed by Rimi Natsukawa; "Yume wo Kanaete Doraemon" , the opening theme broadcast from 2007 to 2018; and "Doraemon" performed by Gen Hoshino, broadcast since October 2019. Numerous collections of theme songs of the anime series and feature films were initially available in cassettes. Since the 1990s, Doraemon songs have been released in CD, under the type of singles and compilation albums. In addition, soundtracks of Doraemon feature films have been released by Nippon Columbia since 2001 in the album series . Other Doraemon has been adapted into a musical, titled . Based on	series was licensed for an English language release in North America, via Amazon Kindle, by a collaboration of Fujiko F. Fujio Pro with Voyager Japan and AltJapan Co., Ltd. The anime series was licensed by Disney for an English-language release in North America in 2014, and LUK International in Europe, the Middle East and Africa. Doraemon received critical acclaim and became a hit in many Asian countries. It won numerous awards, including the Japan Cartoonists Association Award in 1973 and 1994, the Shogakukan Manga Award for children's manga in 1982, and the Tezuka Osamu Cultural Prize in 1997. As of 2012, it has sold over 170 million copies worldwide, becoming one of the best-selling manga in history. Doraemon is also one of the highest-grossing media franchises of all time, of which the animated film series has the highest number of admissions in Japan. The Doraemon character has been viewed as a Japanese cultural icon, and was appointed as the first "anime ambassador" in 2008 by the country's Foreign Ministry. Synopsis Nobita Nobi is a ten-year-old fifth-grade Japanese schoolboy who is kind-hearted and honest but also lazy, unlucky and physically weak. He is often bullied by Takeshi Goda (nicknamed Gian), an irascible and strong-willed bully, and Suneo Honekawa (Gian's sidekick), a wealthy and spoiled boy who uses his friendship with Gian to win the respect of other schoolmates. Nobita's only dream of marrying Shizuka Minamoto, his friend and fellow classmate, is hindered by the presence of Hidetoshi Dekisugi, an intelligent student who exerts a strong attraction on her. Nobita is always reprimanded for his poor grades by the teacher and his parents, Tamako and Nobisuke, who try to encourage him to do more and take responsibility. In spite of this, he continue to descend into failures, which include not being admitted to university; set up a business which eventually burns down, bringing his future family into debt and poverty; and not to marry Shizuka who he was in love with, but Gian's sister, Jaiko. Nobita's grandson from the 22nd century, Sewashi Nobi, decides to send a robot cat named Doraemon back to the past to take care of him, so that his descendants can get a better life. Doraemon has a four-dimensional pouch in which he stores unexpected gadgets he uses to aid Nobita. These gadgets help Nobita overcome the troubles, improving the boy's relationship with his parents and friends. Doraemon quickly befriends Nobita and is extremely thoughtful towards him: he supports Nobita in times of difficulty, but also tries to avoid his gadgets being used recklessly, making problems worse than they initially were. Nobita, although sometimes makes mistakes, still manages to solve his problems with Doraemon's help, doing the right thing and learning his lesson, eventually making him be able to marry Shizuka. Doraemon can thus return to the future; Nobita now has grown up and can deal with life's obstacles on his own. Creation and conception Development and themes Doraemon is written and illustrated by Fujiko F. Fujio, the pen name of Japanese manga artist Hiroshi Fujimoto. According to Fujio, it was originally conceived following a series of three events: when searching for ideas for a new manga, he wished a machine existed that would come up with ideas for him, he tripped over his daughter's toy, and heard cats fighting in his neighborhood. To set up the plot and characters, he inspired some elements from his earlier manga series, Obake no Q-Tarō, which involve an obake living with humans, with a similar formula. Fujio said that the idea for Doraemon came after "an accumulation of trial and error", during which he finally found the most suitable style of manga to him. Initially, the series achieved little success as gekiga was well-known at the time, and only became a hit after its adaptation into an anime TV series and multiple feature films. Doraemon is mainly aimed at children, so Fujio chose to create the character with a simple graphic style, based on shapes such as circles and ellipses. He used the same sequences of cartoons with regularity and continuity to enhance the reader's ease of understanding. In addition, blue, a characteristic color of Doraemon, was chosen as the main color in magazine publications, which used to have a yellow cover and red title. Set in Tokyo, the manga reflected parts of Japan's society, such as the class system and the "ideal" of Japanese childhood. Problems, if occur, were resolved in a way so as not to rely on violence and eroticism, and the stories were integrated with the concept of environmentalism. The manga also insisted on the ethical values of integrity, perseverance, courage, family and respect. In order to underline the crucial role of the young generation in society, the manga's creator chose to have the act carried out in a "children's domain" where young people can live with happiness, freedom and power without adult's interference. As Saya S. Shiraishi noted, the existence of the "domain" helped Doraemon to have a strong appeal in various Asian countries. During Doraemon's development, Fujio did not express a change in characters; he said, "When a manga hero become a success, the manga suddenly stops being interesting. So the hero has to be like the stripes on a barber pole; he seems to keep moving upward, but actually he stays in the same place." According to Zensho Ito, Fujio's former student, the "length" of time in the universe is one of the ideas that inspired Fujio to make Doraemon. Frequently occur in its stories is Nobita's desire to control time, and there exist time-control gadgets that he uses to satisfy that desire, particularly the "Time Machine", which lies in his desk drawer. Unlike Western works on science fiction, the manga did not explain the theory nor the applied technology behind these tools, but instead focusing on how the characters exploit their advantages, making it more children-friendly. Origin of the name The name "Doraemon" can be roughly translated to "stray". Unusually, the name is written in a mixture of two Japanese scripts: Katakana () and Hiragana (). "Dora" derives from , and is a corruption of nora (stray), while "-emon" (in kanji ) is an old-fashioned suffix for male names (for example, as in Ishikawa Goemon). Nobita's home address in Tsukimidai ("moon-view-heights"), Nerima refers to Fujimidai ("Fuji-view-heights"), where Osamu Tezuka's residence and animation studio is based. The name "Nobita Nobi" refers to "nobi nobi", meaning "the way a young child grows up free, healthy, and happy, unrestrained in any sense". Gadgets Gadgets, or , are Doraemon's tools from the future, usually used to help the characters. Fujio said that Doraemon has a total of 1,293 gadgets; according to a 2004 analysis by Yasuyuki Yokoyama of Toyama University, there are 1,963 gadgets found in 1,344 sketches. The most important gadgets include "Take-Copter", a small piece of headgear that can allow its users to fly; "Time Machine", a machine used for time travel; "Anywhere Door", a pink-colored door that allows people to travel according to the thoughts of the person who turns the knob; "Time Kerchief", a handkerchief which can turn an object new or old or a person young or old; "Translator Tool", a cuboid jelly that allow one to converse in any language; and "Designer", a camera used to instantly dress-up the user. Saya S. Shiraishi wrote that most of the gadgets were "an impressive testimony to the standards of quality control and innovation that exist in the twenty-second century". The gadgets were an essential part of the series so as to reflect a positive point of view about the association of technology in children, and to express the wishes of modern society. Conclusion The series stopped publishing after Fujimoto's death in 1996, without an ending; this has aroused numerous urban legends throughout the years. One of the most well-known "endings" of the manga was by an amateur manga cartoonist under the pen name "Yasue T. Tajima", first appeared on the Internet in 1998 and made up into a manga in 2005. The story takes place when Doraemon's battery dies, and Nobita later grows up becoming a robot engineer, potentially revive Doraemon and live a happy life. Tajima issued an apology in 2007, and the profits were shared with Shogakukan and the copyright owner, Fujiko F. Fujio Pro. Ryūichi Yagi and Takashi Yamazaki, the directors of Stand by Me Doraemon, confirmed that it had only one opening, while the ending has been rewritten several times. Because of this, Shogakukan had to clarify that only if the marriage of Nobita and Shizuka is finalized will the mission be accomplished, and then Doraemon will return to the future. Media Manga In December 1969, the Doraemon manga appeared in six different children's monthly magazines published by Shogakukan: Yoiko, Yōchien, Shogaku Ichi-nensei, Shogaku Ni-nensei, Shogaku San-nensei, and Shogaku Yon-nensei. The magazines were aimed at children from nursery school to fourth grade. In 1973, two other magazines, Shogaku Go-nensei and Shogaku Roku-nensei (aimed at fifth-grade and sixth-grade students respectively), started publishing the manga. In 1977, CoroCoro Comic was launched as the flagship magazine of Doraemon. Since the debut of Doraemon in 1969, the stories have been selectively collected into forty-five tankōbon volumes that were published under Shogakukan's imprint from July 31, 1974 to April 26, 1996. These volumes are collected in the Takaoka Central Library in Toyama, Japan, where Fujio was born. Between April 25, 2005 and February 28, 2006, Shōgakukan published a series of five manga volumes under the title Doraemon Plus (Doraemon+), featuring short stories which did not appear in the forty-five original volumes; a sixth volume, the first volume in eight years, was published on December 1, 2014. Additionally, 119 unpublished stories were compiled into six colored-manga volumes under the title Doraemon Kara Sakuhin-shu , published from July 17, 1999 to September 2, 2006. Between July 24, 2009 and September 25, 2012, Shogakukan published a master works collection consisting of twenty volumes with all 1,345 stories written by Fujio. In December 2019, on the 50th anniversary of Doraemon, a "Volume 0" was published by Shogakukan featuring six different versions of Doraemon's first appearance. There have been two series of bilingual, Japanese and English, volumes of the manga by SHOGAKUKAN ENGLISH COMICS under the title Doraemon: Gadget Cat from the Future, and two audio versions. The first series has ten volumes and the second one has six. In addition, 21st Century Publishing House released bilingual English-Chinese versions in Mainland China, and Chingwin Publishing Group released bilingual English-Chinese versions in Taiwan. In July 2013, Fujiko F. Fujio Pro announced that they would be collaborating with ebook publisher Voyager Japan and localization company AltJapan Co., Ltd. to release an English-language version of the manga in full color digitally via the Amazon Kindle platform in North America. Shogakukan released the first volume in November 2013; as of 2016, a total of 200 volumes have been published. This English version incorporates a variety of changes to character names; Nobita is "Noby", Shizuka is "Sue", Suneo is "Sneech", and Gian is "Big G", while dorayaki is "Yummy Bun/Fudgy Pudgy Pie". Also, as of 2016, four volumes of the manga have been published in English in print by Shogakukan Asia. Shogakukan started digital distribution of all forty-five original volumes throughout Japan from July 16, 2015. Anime The first attempt of a Doraemon animated series was in 1973, by Nippon Television. After a January 1973 pilot named Doraemon Mirai Kara Yattekuru , twenty-six episodes, each with two segments, were broadcast on Nippon TV from April 1 to September 30 of the same year. The series was directed by Mitsuo Kaminashi with voice cast from Aoni Production; the character Doraemon was voiced by Kōsei Tomita, then later by Masako Nozawa. Later in the series, the animation studio, Nippon TeleMovie Productions, went bankrupt, and the masters were sold off or destroyed. The series was re-aired on Nippon TV and several local stations until 1979, when Shogakukan requested Toyama Television to cease broadcasting. Some of the segments were found in the archives of IMAGICA in 1995, and some others were recovered by Jun Masami in 2003. As of 2013, 21 of 52 segments have known to survive, two of which without audio. Doraemon remained fairly exclusive in manga form until 1979 when a newly formed animation studio, Shin-Ei Animation (now owned by TV Asahi) produced an animated second attempt of Doraemon. The series, directed by Tsutomu Shibayama, aired on TV Asahi from April 2, 1979 to March 18, 2005. Eiichi Nakamura served as director of photography and character designer, while Shunsuke Kikuchi was the composer. Nobuyo Ōyama voiced Doraemon in the series; because of this, in Asia, this version is sometimes referred to as the Ōyama Edition. In total, 1,787 episodes were produced and released in VHS and DVD by Toho. Celebrating the anniversary of the franchise, a third Doraemon animated series, also produced by Shin-Ei Animation, began airing on TV Asahi on April 15, 2005, with new voice actors and staff, and updated character designs. The third series is sometimes referred to in Asia as the Mizuta Edition, as a tribute for the voice actress for Doraemon, Wasabi Mizuta. It was released in DVD on February 10, 2006 under the title New TV-ban Doraemon with Shogakukan Video banner. In May 2014, TV Asahi Corporation announced an agreement with The Walt Disney Company to bring the 2005 series to the Disney XD television channel in the United States beginning in the summer of that year. Besides using the name changes that were used in AltJapan's English adaptation of the original manga, other changes and edits have also been made to make the show more relatable to an American audience, such as Japanese text being replaced with English text on certain objects like signs and graded papers, items such as yen notes being replaced by US dollar bills, and the setting being changed from Japan to the United States. Initial response to the edited dub was positive. The Disney adaptation began broadcast in Japan on Disney Channel from February 1, 2016. The broadcast offered the choice of the English voice track or a newly recorded Japanese track by the Japanese cast of the 2005 series. In addition, the anime has been aired in over sixty countries worldwide. It premiered in Thailand in 1982, the Philippines in 1999, India in 2005, and Vietnam in 2010. Other Asian countries that broadcast the series include China, Hong Kong, Singapore, Taiwan,
to be. National Park designation The National Parks and Access to the Countryside Act 1949 led to Dartmoor being one of the first four parks to be designated, by an order made on 15 August 1951 and confirmed on 30 October 1951. Shortly after this, the DPA tried to ensure that the new National Park was run by an independent committee and not by the Dartmoor Standing Committee that was a subcommittee of Devon County Council Planning Committee. The committee was reformed as Dartmoor National Park Committee under the Local Government Act 1972 but it was still a subcommittee of Devon County Council and as such it was not seen to be an independent guardian of the moor by the DPA. It was not until 1997 that an independent Dartmoor National Park Authority was enabled under the Environment Act 1995 as a free-standing local authority, forty-four years after the park was created, although it is still dominated by local authorities and government appointees. North Hessary Tor TV mast The DPA learned in October 1951 that the BBC planned to build a 750-foot television mast on North Hessary Tor, near Princetown, that was erected in 1955. This was to be a relay from a transmitting station at Wenvoe, South Wales. The DPA objected to this threat and sought expert opinion, offered alternative solutions, pressed for a public enquiry, engaged a lawyer, held public meetings, distributed pamphlets, wrote to the press and petitioned parliament. Eventually, a public enquiry was announced. When the decision was made to permit the mast, there were a number of conditions, included among them was that the development was built near the tor, leaving it still intact, and that its new approach road should not be fenced. During the process of obtaining land for the transmitter, one MP asked in the House of Commons: "Will the Assistant Postmaster-General bear in mind that we have no desire to hinder the provision of this station but that it is felt that ancient common rights such as these, that have existed for a thousand years, should be adequately protected or properly extinguished by due process of law?" Sharpitor During World War II, the Royal Air Force (RAF) built a mast and buildings on Peek Hill, as RAF Sharpitor. In 1956, permission was granted to rebuild the station as part of the "Gee" radio navigation system, to be occupied for ten years. There followed delay in leaving and a proposal was made in 1970 by Devon & Cornwall Police to use the mast, which was rejected. Then later that year Plymouth Corporation wanted to use the exposed site for housing juvenile offenders. This was also rejected, but Plymouth appealed. At a public enquiry in June 1973 Lady Sylvia Sayer represented the DPA and permission for development on the site was refused. A few years later, DPA fought successfully in support of South West Water (SWW) against renewed calls for a new reservoir at Swincombe. To mark the victory, Sylvia Sayer asked SWW if DPA could purchase the rocky outcrop of Sharpitor. The DPA purchased 32 acres in February 1984. Okehampton bypass Okehampton lies on the A30 main road, the shortest route from London to west Devon and Cornwall. The need for a bypass was mooted in 1963. In 1975, three routes were considered: a northern route through mainly farmland, a central route using a railway, and a southern route through Dartmoor National Park. In August 1976, the Department of the Environment announced the preferred route was through the National Park. A major event on the timeline of this project was a 96-day public enquiry from 1 May 1979 to 4 February 1980 held in Okehampton. In March 1984, the DPA with other organisations petitioned Parliament opposing compulsory purchase orders on public open spaces. The Secretary of State announced in July 1985 that he was introducing a bill to reverse the decision of a Joint Parliamentary Committee and confirm a route through the National Park. This was followed by a confirmation bill in November 1985 that was passed in the House of Lords on 5 December 1985. Construction started in November 1986 and the road was opened on 19 July 1988. Since 2000 The DPA continues to follow the same objectives as when it was founded. The activities have widened, involving local partners, it has a calendar of events, walks and work days with its Conservation Team undertaking a variety of moorland projects, it funds the supply of walking boots to some children who need them for the Duke of Edinburgh Award Scheme through the Moor Boots Scheme, it collaborates with the Campaign for National Parks, it monitors the activities of Dartmoor National Park Authority who run the National Park. It objected to eight planning proposals (with success in seven cases), with many other achievements in the DPA Director's Annual Report. The DPA remains true to its original objectives and has also added other activities in support of Dartmoor and its inhabitants. China clay expansion The china clay industry on Dartmoor was established long before the DPA was founded. The earliest record of a china clay pit refers to Hook Lake in 1502. The area was surveyed around 1827 by Cornishmen with thirty years experience in the clay industry. They obtained a 21-year lease in 1830, from the Earl of Morley who owned the land, to work the area between Lee Moor and Shaugh Moor. A rival pit was opened at Leftlake in about 1850 and at Hemerdon and Broomage in about 1855. Further pits were opened at Cholwichtown, Whitehill Yeo and Wigford Down/Brisworthy (circa 1860). Others followed at Smallhanger and Headon in the 1870s. Redlake started working in 1910. China clay pits are open cast mines that result in large holes in the ground accompanied by large waste tips. Over time, the pits become larger and more ground is needed for the waste, changing the landscape: the effect of this can be seen from space. The DPA argues that this is an activity that does not agree with the ethos of a National Park, whose purpose is to protect landscape from unsuitable development. In 1994, the National Park boundaries were changed to include common land at Shaugh Moor and exclude china clay worked land at Lee Moor. The DPA revived its campaign with the publication of a booklet in 1999 when the Blackabrook Valley, Crownhill Down and Shaugh Moor, near the popular tourist area of Cadover Bridge, all came under threat from exploitation or dumping of waste. The china clay companies relinquished planning permissions in 2001. However, in November 2009, the clay companies, Sibelco and Imerys, produced a report reviewing old mineral permissions under the Environment Act 1995 with a view to joining up two pits. A presumed Bronze Age barrow, known as Emmets Post, was to be removed and three other monuments may be affected. The DPA were recorded twice, with other bodies, in a Devon County Council Development Management Committee Report for their representations in securing the future of the three areas where planning permissions were relinquished in 2001. Oxford Archaeology held an open day during their excavation of Emmets Post in 2014 prior to its removal. House of Lords reception The DPA and Exmoor Society held a joint reception at the House of Lords on 6 November 2008, hosted by Baroness Mallalieu, to lobby members of both Houses of Parliament and relevant Ministers about ensuring that environmental schemes for the uplands are "fit for purpose". Both organisations funded an invited number of upland hill farmers to attend. Whitehorse Hill excavation The excavation in August 2011 on the north moor of a Bronze Age burial kistvaen, or cist, that was originally uncovered in 2001 was part-funded by the DPA, along with other bodies. South West Uplands Federation Conference A conference for the upland farmers of Bodmin Moor, Exmoor and Dartmoor was held as a joint venture between the South West Uplands Federation and the DPA. It was run by the DPA at Exeter Racecourse in October 2012, with 150 delegates. Speakers came from the Foundation for Common Land, the Forest of Dartmoor Commoners, the University of Gloucestershire, the National Farmers Union of England and Wales and the Open Spaces Society. The CEO raised sponsorship from Dartmoor National Park, Exmoor National Park, Natural England, Duchy of Cornwall and the Exmoor Society - this reflecting the standing of the DPA with those bodies. Undergrounding power cables Two major projects to underground overhead power cables in Dartmoor National Park have been completed in a joint project between Western Power Distribution, the South West Protected Landscapes Forum (SWPLF) and Dartmoor National Park Authority. The two schemes on Holne Moor and Walkhampton Common between them remove nearly 6 km of overhead line from open moorland. At nearly 5 km, the Walkhampton scheme is the largest to be undertaken in the South West region by Western Power Distribution. The old overhead line was readily visible from the B3212 Princetown to Yelverton Road, strung across Walkhampton Common from Devil's Elbow to just above Horseyeatt at Peek Hill. The works to provide the new underground supply were mainly undertaken on the highway to minimise the impact on the sensitive moorland landscape, its archaeology, wildlife and livestock. The DPA has supported the undergrounding of these visually intrusive power lines for many years. The Dartmoor Conservation Garden The Dartmoor Conservation Garden is a joint project between DPA and Dartmoor National Park Authority (DNPA) and is located in the Jack Wigmore Garden behind the High Moorland Centre in Princetown: this is a memorial	activities in support of Dartmoor and its inhabitants. China clay expansion The china clay industry on Dartmoor was established long before the DPA was founded. The earliest record of a china clay pit refers to Hook Lake in 1502. The area was surveyed around 1827 by Cornishmen with thirty years experience in the clay industry. They obtained a 21-year lease in 1830, from the Earl of Morley who owned the land, to work the area between Lee Moor and Shaugh Moor. A rival pit was opened at Leftlake in about 1850 and at Hemerdon and Broomage in about 1855. Further pits were opened at Cholwichtown, Whitehill Yeo and Wigford Down/Brisworthy (circa 1860). Others followed at Smallhanger and Headon in the 1870s. Redlake started working in 1910. China clay pits are open cast mines that result in large holes in the ground accompanied by large waste tips. Over time, the pits become larger and more ground is needed for the waste, changing the landscape: the effect of this can be seen from space. The DPA argues that this is an activity that does not agree with the ethos of a National Park, whose purpose is to protect landscape from unsuitable development. In 1994, the National Park boundaries were changed to include common land at Shaugh Moor and exclude china clay worked land at Lee Moor. The DPA revived its campaign with the publication of a booklet in 1999 when the Blackabrook Valley, Crownhill Down and Shaugh Moor, near the popular tourist area of Cadover Bridge, all came under threat from exploitation or dumping of waste. The china clay companies relinquished planning permissions in 2001. However, in November 2009, the clay companies, Sibelco and Imerys, produced a report reviewing old mineral permissions under the Environment Act 1995 with a view to joining up two pits. A presumed Bronze Age barrow, known as Emmets Post, was to be removed and three other monuments may be affected. The DPA were recorded twice, with other bodies, in a Devon County Council Development Management Committee Report for their representations in securing the future of the three areas where planning permissions were relinquished in 2001. Oxford Archaeology held an open day during their excavation of Emmets Post in 2014 prior to its removal. House of Lords reception The DPA and Exmoor Society held a joint reception at the House of Lords on 6 November 2008, hosted by Baroness Mallalieu, to lobby members of both Houses of Parliament and relevant Ministers about ensuring that environmental schemes for the uplands are "fit for purpose". Both organisations funded an invited number of upland hill farmers to attend. Whitehorse Hill excavation The excavation in August 2011 on the north moor of a Bronze Age burial kistvaen, or cist, that was originally uncovered in 2001 was part-funded by the DPA, along with other bodies. South West Uplands Federation Conference A conference for the upland farmers of Bodmin Moor, Exmoor and Dartmoor was held as a joint venture between the South West Uplands Federation and the DPA. It was run by the DPA at Exeter Racecourse in October 2012, with 150 delegates. Speakers came from the Foundation for Common Land, the Forest of Dartmoor Commoners, the University of Gloucestershire, the National Farmers Union of England and Wales and the Open Spaces Society. The CEO raised sponsorship from Dartmoor National Park, Exmoor National Park, Natural England, Duchy of Cornwall and the Exmoor Society - this reflecting the standing of the DPA with those bodies. Undergrounding power cables Two major projects to underground overhead power cables in Dartmoor National Park have been completed in a joint project between Western Power Distribution, the South West Protected Landscapes Forum (SWPLF) and Dartmoor National Park Authority. The two schemes on Holne Moor and Walkhampton Common between them remove nearly 6 km of overhead line from open moorland. At nearly 5 km, the Walkhampton scheme is the largest to be undertaken in the South West region by Western Power Distribution. The old overhead line was readily visible from the B3212 Princetown to Yelverton Road, strung across Walkhampton Common from Devil's Elbow to just above Horseyeatt at Peek Hill. The works to provide the new underground supply were mainly undertaken on the highway to minimise the impact on the sensitive moorland landscape, its archaeology, wildlife and livestock. The DPA has supported the undergrounding of these visually intrusive power lines for many years. The Dartmoor Conservation Garden The Dartmoor Conservation Garden is a joint project between DPA and Dartmoor National Park Authority (DNPA) and is located in the Jack Wigmore Garden behind the High Moorland Centre in Princetown: this is a memorial garden to a former Chair of the Authority. It is planted with a cross-section of typical native Dartmoor plants. It also houses some typical Dartmoor archaeological features, such as a 4,000-year-old Bronze Age burial kistvaen (or cist) and a Medieval granite cross from Ter Hill. This marked the Monk's Path but was constantly being pushed over by cattle. The purpose of the Garden is to illustrate the biodiversity on Dartmoor. The project came online in June 2015. Widecombe telecommunications mast The DPA were involved in a campaign in June 2015 against four telecommunications masts planned for Dartmoor, with the first to be erected in the village of Widecombe. At short notice, the DPA banners were taken out, letters written, press interviews given and support given to the villagers when an inflatable mast was demonstrated – with the effect that the planning application was withdrawn. Friends of Dartmoor In common with other amenity bodies, such as those for the Lake District, Peak District, Pembrokeshire Coast, Yorkshire Dales Three Peaks and the New Forest Trust, the image of Dartmoor Preservation Association is evolving from its Victorian origins, although the original name is being retained. Friends of Dartmoor projects a more modern image of preservation where several years of diplomacy have achieved good relations with the partner agencies that operate in the Dartmoor arena. This is due mainly to the efforts of the previous CEO, James Paxman and his successor, Phil Hutt. Constitution, objectives and policies The DPA Constitution, objectives and policies are published on the DPA web site. The objectives enshrined in the constitution are the protection, preservation and enhancement in the public interest of the landscape, antiquities, flora and fauna, natural beauty, cultural heritage and scientific interest of Dartmoor. Also the protection and preservation of public access to and on Dartmoor subject to the ancient rights of commoners. Co-operation with the commoners and any organisation in achieving DPA objectives, also the study of and the recording and publication of information upon the antiquities, history and natural history of Dartmoor. There is also an interest in the acquisition of land and rights to further DPA objectives, concomitant with being a charity. The DPA has twenty-two policies listed on its web site: regarding access and rights of way, fencing, protecting monuments, diverse habitats, bracken, china clay quarrying, military training and live firing, hill farming and small scale traditional local industries, quarrying, television and telephone masts, wind farms, planning applications, housing developments, woodlands and forestry, ponies, swaling, and recreational activities. Logo The DPA logo incorporates a representation of a Dartmoor rock feature known as Bowerman's Nose. The logo that includes a representation of Nun's Cross appeared on the DPA Dartmoor Newsletter No. 48, October 1966, with a comment that designs based on the initial letters DPA had been exhausted. The simpler logo appeared in November 1969, when Newsletter 52 carried the logo with "DPA" on it. This was replaced in 2004 with the multicoloured logo. References Further reading Brewer, Dave. Dartmoor Boundary Markers. Halsgrove. Tiverton, Devon, 2002. Crossing, William. Crossing’s Dartmoor Worker. 2nd Edn. Peninsula Press, Newton Abbot, Devon, 1992. Dartmoor Preservation Association. "The Meldon Story". DPA Publication No. 7. Crapstone, Plymouth, 1972. UIN BLL01004145656. Greeves, Tom. Tin Mines and Miners of Dartmoor: A Photographic Record. Devon Books, Kingkerswell, Devon, 1986. . Greeves, Tom. "Sacred Land – Working Land: the case for the preservation of the Blackabrook Valley, Crownhill Down and Shaugh Moor from the expansion of the china clay industry." Dartmoor Preservation Association, Princetown, 1999. . Harris, Helen. Industrial Archaeology of Dartmoor. David & Charles, Newton Abbot, Devon, 1968. . Hemery, Eric. High Dartmoor. Robert Hale Ltd, London, 1983. Kelly, Matthew. Quartz and Feldspar: Dartmoor - A British Landscape in Modern Times, Jonathan Cape, London, 2015. Moore, Stuart A. "A short history of the rights of common upon the Forest of Dartmoor and the commons of Devon". Dartmoor Preservation Association, Plymouth, 1890. Newman, Phil. The Dartmoor Tin Industry: A Field Guide. Newton Abbot, Devon, 1968. . Somers Cocks, John. "Exploitation". In Dartmoor:
to reduce the problems of lack of social and academic continuity. Board of Trustees Dartmouth is governed by a Board of Trustees comprising the college president (ex officio), the state governor (ex officio), 13 trustees nominated and elected by the board (called "charter trustees"), and eight trustees nominated by alumni and elected by the board ("alumni trustees"). The nominees for alumni trustee are determined by a poll of the members of the Association of Alumni of Dartmouth College, selecting from among names put forward by the Alumni Council or by alumni petition. Although the board elected its members from the two sources of nominees in equal proportions between 1891 and 2007, the board decided in 2007 to add several new members, all charter trustees. In the controversy that followed the decision, the Association of Alumni filed a lawsuit, although it later withdrew the action. In 2008, the Board added five new charter trustees. Campus Dartmouth College is situated in the rural town of Hanover, New Hampshire, located in the Upper Valley along the Connecticut River in New England. Its campus is centered on a "Green", a former field of pine trees cleared in 1771. Dartmouth is the largest private landowner of the town of Hanover, and its total landholdings and facilities are worth an estimated $434 million. In addition to its campus in Hanover, Dartmouth owns of Mount Moosilauke in the White Mountains and a tract of land in northern New Hampshire known as the Second College Grant. Dartmouth's campus buildings vary in age from Wentworth and Thornton Halls of the 1820s (the oldest surviving buildings constructed by the college) to new dormitories and mathematics facilities completed in 2006. Most of Dartmouth's buildings are designed in the Georgian colonial architecture style, a theme which has been preserved in recent architectural additions. The College has actively sought to reduce carbon emissions and energy usage on campus, earning it the grade of A- from the Sustainable Endowments Institute on its College Sustainability Report Card 2008. A notable feature of the Dartmouth campus is its many trees which (despite Dutch elm disease) include some 200 American elms. The campus also has the largest Kentucky coffeetree in New Hampshire, at 91 ft tall. Academic facilities The college's creative and performing arts facility is the Hopkins Center for the Arts ("the Hop"). Opened in 1962, the Hop houses the College's drama, music, film, and studio arts departments, as well as a woodshop, pottery studio, and jewelry studio which are open for use by students and faculty. The building was designed by the famed architect Wallace Harrison, who would later design the similar-looking façade of Manhattan's Metropolitan Opera House at Lincoln Center. Its facilities include two theaters and one 900-seat auditorium. The Hop is also the location of all student mailboxes ("Hinman boxes") and the Courtyard Café dining facility. The Hop is connected to the Hood Museum of Art, arguably North America's oldest museum in continuous operation, and the Loew Auditorium, where films are screened. In addition to its 19 graduate programs in the arts and sciences, Dartmouth is home to three separate graduate schools. The Geisel School of Medicine is located in a complex on the north side of campus and includes laboratories, classrooms, offices, and a biomedical library. The Dartmouth–Hitchcock Medical Center, located several miles to the south in Lebanon, New Hampshire, contains a 396-bed teaching hospital for the Medical School. The Thayer School of Engineering and the Tuck School of Business are both located at the end of Tuck Mall, west of the center of campus and near the Connecticut River. The Thayer School comprises two buildings; Tuck has seven academic and administrative buildings, as well as several common areas. The two graduate schools share a library, the Feldberg Business & Engineering Library. In December 2018, Dartmouth began a major expansion of the west end by breaking ground on the $200 million Center for Engineering and Computer Science. The Center will house the Computer Science department and Magnuson Center for Entrepreneurship. In October 2019, construction began on the Irving Institute of Energy and Society. Both are scheduled to be completed by fall 2021. Dartmouth's libraries are all part of the collective Dartmouth College Library, which comprises 2.48 million volumes and 6 million total resources, including videos, maps, sound recordings, and photographs. Its specialized libraries include the Biomedical Libraries, Evans Map Room, Feldberg Business & Engineering Library, Jones Media Center, Rauner Special Collections Library, and Sherman Art Library. Baker-Berry Library is the main library at Dartmouth, consisting of a merger of the Baker Memorial Library (opened 1928) and the Berry Library (completed 2002). Located on the northern side of the Green, Baker's tower is an iconic symbol of the College. Athletic facilities Dartmouth's original sports field was the Green, where students played cricket and old division football during the 19th century. Today, two of Dartmouth's athletic facilities are located in the southeast corner of campus. The center of athletic life is the Alumni Gymnasium, which includes the Karl Michael Competition Pool and the Spaulding Pool, a state of the art fitness center, a weight room, and a 1/13th-mile (123 m) indoor track. Attached to Alumni Gymnasium is the Berry Sports Center, which contains basketball and volleyball courts (Leede Arena), as well as the Kresge Fitness Center. Behind the Alumni Gymnasium is Memorial Field, a 15,600-seat stadium overlooking Dartmouth's football field and track. The nearby Thompson Arena, designed by Italian engineer Pier Luigi Nervi and constructed in 1975, houses Dartmouth's ice rink. Also visible from Memorial Field is the Nathaniel Leverone Fieldhouse, home to the indoor track. The new softball field, Dartmouth Softball Park, was constructed in 2012, sharing parking facilities with Thompson arena and replacing Sachem Field, located over a mile from campus, as the primary softball facility. Dartmouth's other athletic facilities in Hanover include the Friends of Dartmouth Rowing Boathouse and the old rowing house storage facility (both located along the Connecticut River), the Hanover Country Club, Dartmouth's oldest remaining athletic facility (established in 1899), and the Corey Ford Rugby Clubhouse. The college also maintains the Dartmouth Skiway, a skiing facility located over two mountains near the Hanover campus in Lyme Center, New Hampshire, that serves as the winter practice grounds for the Dartmouth ski team, which is a perennial contender for the NCAA Division I championship. Dartmouth's close association and involvement in the development of the downhill skiing industry is featured in the 2010 book Passion for Skiing as well as the 2013 documentary based on the book Passion for Snow. Residential housing and student life facilities Beginning in the fall term of 2016, Dartmouth placed all undergraduate students in one of six House communities, similar to residential colleges, including Allen House, East Wheelock House, North Park House, School House, South House, and West House, alongside independent Living Learning Communities. Dartmouth used to have nine residential communities located throughout campus, instead of ungrouped dormitories or residential colleges. The dormitories varied in design from modern to traditional Georgian styles, and room arrangements range from singles to quads and apartment suites. Since 2006, the college has guaranteed housing for students during their freshman and sophomore years. More than 3,000 students elect to live in housing provided by college. Campus meals are served by Dartmouth Dining Services, which operates 11 dining establishments around campus. Four of them are located at the center of campus in the Class of 1953 Commons, formerly Thayer Dining Hall. The Collis Center is the center of student life and programming, serving as what would be generically termed the "student union" or "campus center". It contains a café, study space, common areas, and a number of administrative departments, including the Academic Skills Center. Robinson Hall, next door to both Collis and Thayer, contains the offices of a number of student organizations including the Dartmouth Outing Club and The Dartmouth daily newspaper. Residential House communities of Dartmouth College Student life In 2006, The Princeton Review ranked Dartmouth third in its "Quality of Life" category, and sixth for having the "Happiest Students". Athletics and participation in the Greek system are the most popular campus activities. In all, Dartmouth offers more than 350 organizations, teams, and sports. The school is also home to a variety of longstanding traditions and celebrations and has a loyal alumni network; Dartmouth ranked #2 in "The Princeton Review" in 2006 for Best Alumni Network. Student safety In 2014, Dartmouth College was the third highest in the nation in "total of reports of rape" on their main campus, with 42 reports of rape. The Washington Post attributed the high number of rape reports to the fact that a growing number of sexual assault victims feel comfortable enough to report sexual assaults that would have gone unreported in previous years. In 2015, the Huffington Post reported that Dartmouth College had the highest rate of bystander intervention of any college surveyed, with 57.7% of Dartmouth students reporting that they would take some sort of action if they saw someone acting in a "sexually violent or harassing manner", compared to 45.5% of students nationally. Dartmouth fraternities have an extensive history of hazing and alcohol abuse, leading to police raids and accusations of sexual harassment. Student groups Dartmouth's more than 200 student organizations and clubs cover a wide range of interests. In 2007, the college hosted eight academic groups, 17 cultural groups, two honor societies, 30 "issue-oriented" groups, 25 performing groups, 12 pre-professional groups, 20 publications, and 11 recreational groups. Notable student groups include the nation's largest and oldest collegiate outdoors club, the Dartmouth Outing Club, which includes the nationally recognized Big Green Bus; the campus's oldest a cappella group, The Dartmouth Aires; the controversial conservative newspaper The Dartmouth Review; and The Dartmouth, arguably the nation's oldest university newspaper. The Dartmouth describes itself as "America's Oldest College Newspaper, Founded 1799". Partially because of Dartmouth's rural, isolated location, the Greek system dating from the 1840s is one of the most popular social outlets for students. Dartmouth is home to 32 recognized Greek houses: 17 fraternities, 12 sororities, and three coeducational organizations. In 2007, roughly 70% of eligible students belonged to a Greek organization; since 1987, students have not been permitted to join Greek organizations until their sophomore year. Dartmouth College was among the first institutions of higher education to desegregate fraternity houses in the 1950s, and was involved in the movement to create coeducational Greek houses in the 1970s. In the early first decade of the 21st century, campus-wide debate focused on a Board of Trustees recommendation that Greek organizations become "substantially coeducational"; this attempt to change the Greek system eventually failed. Dartmouth also has a number of secret societies, which are student- and alumni-led organizations often focused on preserving the history of the college and initiating service projects. Most prominent among them is the Sphinx society, housed in a prominent Egyptian tomb-like building near the center of campus. The Sphinx has been the subject of numerous rumors as to its facilities, practices, and membership. The college has an additional classification of social/residential organizations known as undergraduate societies. Athletics Approximately 20% of students participate in a varsity sport, and nearly 80% participate in some form of club, varsity, intramural, or other athletics. In 2021, Dartmouth College fielded 33 intercollegiate varsity teams: 15 for men, 17 for women, and coeducational sailing and equestrian programs. Dartmouth's athletic teams compete in the NCAA Division I eight-member Ivy League conference; some teams also participate in the Eastern College Athletic Conference (ECAC). As is mandatory for the members of the Ivy League, Dartmouth College does not offer athletic scholarships. In addition to the traditional American team sports (football, basketball, baseball, and ice hockey), Dartmouth competes at the varsity level in many other sports including track and field, softball, squash, sailing, tennis, rowing, soccer, skiing, and lacrosse. The college also offers 26 club and intramural sports such as fencing, rugby, water polo, figure skating, boxing, volleyball, ultimate frisbee, and cricket, leading to a 75% participation rate in athletics among the undergraduate student body. The Dartmouth Fencing Team, despite being entirely self-coached, won the USACFC club national championship in 2014. The Dartmouth Men's Rugby Team, founded in 1951, has been ranked among the best collegiate teams in that sport, winning for example the Ivy Rugby Conference every year between 2008 and 2020. The figure skating team won the national championship five straight times from 2004 through 2008. In addition to the academic requirements for graduation, Dartmouth requires every undergraduate to complete a swim and three terms of physical education. Native Americans at Dartmouth The charter of Dartmouth College, granted to Wheelock in 1769, proclaims that the institution was created "for the education and instruction of Youth of the Indian Tribes in this Land in reading, writing and all parts of Learning ... as well as in all liberal Arts and Sciences; and also of English Youth and any others". However, Wheelock primarily intended the college to educate white youth, and the few Native students that attended Dartmouth experienced much difficulty in an institution ostensibly dedicated to their education. The funds for the Charity School for Native Americans that preceded Dartmouth College were raised primarily by the efforts of a Mohegan named Samson Occom, and at least some of those funds were used to help found the college. The college graduated only 19 Native Americans during its first 200 years. In 1970, the college established Native American academic and social programs as part of a "new dedication to increasing Native American enrollment". Since then, Dartmouth has graduated over 700 Native American students	raised primarily by the efforts of a Mohegan named Samson Occom, and at least some of those funds were used to help found the college. The college graduated only 19 Native Americans during its first 200 years. In 1970, the college established Native American academic and social programs as part of a "new dedication to increasing Native American enrollment". Since then, Dartmouth has graduated over 700 Native American students from over 200 different tribes, more than the other seven Ivy League universities combined. Traditions Dartmouth is well known for its fierce school spirit and many traditions. The college functions on a quarter system, and one weekend each term is set aside as a traditional celebratory event, known on campus as "big weekends" or "party weekends". In the fall term, Homecoming (officially called Dartmouth Night) is marked by a bonfire on the Green constructed by the freshman class. Winter term is celebrated by Winter Carnival, a tradition started in 1911 by the Dartmouth Outing Club to promote winter sports. This tradition is the oldest in the United States, and subsequently went on to catch on at other New England colleges. In the spring, Green Key is a weekend mostly devoted to campus parties and celebration. The summer term was formerly marked by Tubestock, an unofficial tradition in which the students used wooden rafts and inner tubes to float on the Connecticut River. Begun in 1986, Tubestock was ended in 2006 by town ordinance. The Class of 2008, during their summer term on campus in 2006, replaced the defunct Tubestock with Fieldstock. This new celebration includes a barbecue, live music, and the revival of the 1970s and 1980s tradition of racing homemade chariots around the Green. Unlike Tubestock, Fieldstock is funded and supported by the College. Another longstanding tradition is four-day, student-run Dartmouth Outing Club trips for incoming freshmen, begun in 1935. Each trip concludes at the Moosilauke Ravine Lodge. In 2011, over 96% of freshmen elected to participate. Insignia and other representations Motto and song Dartmouth's motto, chosen by Eleazar Wheelock, is Vox clamantis in deserto. The Latin motto is literally translated as "The voice of one crying in the wilderness", but is more often rendered as "A voice crying out in the wilderness". The phrase appears five times in the Bible and is a reference to the college's location on what was once the frontier of European settlement. Richard Hovey's "Men of Dartmouth" was elected as the best of Dartmouth's songs in 1896, and became the school's official song in 1926. The song was retitled to "Alma Mater" in the 1980s when its lyrics were changed to refer to women as well as men. Seal Dartmouth's 1769 royal charter required the creation of a seal for use on official documents and diplomas. The college's founder, Eleazar Wheelock, designed a seal for his college bearing a striking resemblance to the seal of the Society for the Propagation of the Gospel, a missionary society founded in London in 1701, in order to maintain the illusion that his college was more for mission work than for higher education. Engraved by a Boston silversmith, the seal was ready by commencement of 1773. The trustees officially accepted the seal on August 25, 1773, describing it as: On October 28, 1926, the trustees affirmed the charter's reservation of the seal for official corporate documents alone. The College Publications Committee commissioned noted typographer William Addison Dwiggins to create a line drawing version of the seal in 1940 that saw widespread use. Dwiggins' design was modified during 1957 to change the date from "1770" to "1769", to accord with the date of the college charter. The trustees commissioned a new set of dies with a date of "1769" to replace the old dies, now badly worn after almost two hundred years of use. The 1957 design continues to be used under trademark number 2305032. Shield On October 28, 1926, the trustees approved a "Dartmouth College Shield" for general use. Artist and engraver W. Parke Johnson designed this emblem on the basis of the shield that is depicted at the center of the original seal. This design does not survive. On June 9, 1944, the trustees approved another coat of arms based on the shield part of the seal, this one by Canadian artist and designer Thoreau MacDonald. That design was used widely and, like Dwiggins' seal, had its date changed from "1770" to "1769" around 1958. That version continues to be used under trademark registration number 3112676 and others. College designer John Scotford made a stylized version of the shield during the 1960s, but it did not see the success of MacDonald's design. The shield appears to have been used as the basis of the shield of Dartmouth Medical School, and it has been reproduced in sizes as small as 20 micrometers across. The design has appeared on Rudolph Ruzicka's Bicentennial Medal (Philadelphia Mint, 1969) and elsewhere. Nickname, symbol, and mascot Dartmouth has never had an official mascot. The nickname "The Big Green", originating in the 1860s, is based on students' adoption of a shade of forest green ("Dartmouth Green") as the school's official color in 1866. Beginning in the 1920s, the Dartmouth College athletic teams were known by their unofficial nickname "the Indians", a moniker that probably originated among sports journalists. This unofficial mascot and team name was used until the early 1970s, when its use came under criticism. In 1974, the Trustees declared the "use of the [Indian] symbol in any form to be inconsistent with present institutional and academic objectives of the College in advancing Native American education". Some alumni and students, as well as the conservative student newspaper, The Dartmouth Review, have sought to return the Indian symbol to prominence, but never succeeded in doing so. Various student initiatives have been undertaken to adopt a mascot, but none has become "official". One proposal devised by the college humor magazine the Dartmouth Jack-O-Lantern was Keggy the Keg, an anthropomorphic beer keg who makes occasional appearances at college sporting events. Despite student enthusiasm for Keggy, the mascot has received approval from only the student government. In November 2006, student government attempted to revive the "Dartmoose" as a potential replacement amid renewed controversy surrounding the former unofficial Indian mascot. Alumni Dartmouth's alumni are known for their devotion to the college. Most start by giving to the Senior Class Gift. According to a 2008 article in The Wall Street Journal based on data from payscale.com, Dartmouth graduates also earn higher median salaries at least 10 years after graduation than alumni of any other American university surveyed. By 2008, Dartmouth had graduated 238 classes of students, and had over 60,000 living alumni in a variety of fields. Finance, consulting, and technology have consistently been the most popular industries to enter for students. Top employers of new graduates include Goldman Sachs, Morgan Stanley, McKinsey & Company, Bain & Company, Amazon, Microsoft, Google, and Teach for America. The most common graduate and professional schools for Dartmouth undergraduates include other members of the Ivy Plus, Icahn School of Medicine, NYU, Oxford, and Cambridge. Nelson A. Rockefeller, 41st Vice President of the United States and 49th Governor of New York, graduated cum laude from Dartmouth with a degree in economics in 1930. Over 164 Dartmouth graduates have served in the United States Senate and United States House of Representatives, such as Massachusetts statesman Daniel Webster. Cabinet members of American presidents include Attorney General Amos T. Akerman, Secretary of Defense James V. Forrestal, Secretary of Labor Robert Reich, Secretary of the Treasury Henry Paulson, and Secretary of the Treasury Timothy Geithner. C. Everett Koop was the Surgeon General of the United States under President Ronald Reagan. Two Dartmouth alumni have served as justices on the Supreme Court of the United States: Salmon P. Chase and Levi Woodbury. Eugene Norman Veasey (class of 1954) served as the Chief Justice of Delaware. The 46th Governor of Pennsylvania, Tom Wolf; the 42nd Governor of Illinois, businessman Bruce Rauner; and the 31st governor and current senator from North Dakota, John Hoeven (R), are also Dartmouth alumni. Ernesto de la Guardia, class of 1925, was president of the Republic of Panama. In literature and journalism, Dartmouth has produced 13 Pulitzer Prize winners: Thomas M. Burton, Richard Eberhart, Dan Fagin, Paul Gigot, Frank Gilroy, Jake Hooker, Nigel Jaquiss, Joseph Rago, Martin J. Sherwin, David K. Shipler, David Shribman, Justin Harvey Smith and Robert Frost. Frost, who received four Pulitzer Prizes for Poetry in his lifetime, attended but did not graduate from Dartmouth; he is, however, the only person to have received two honorary degrees from Dartmouth. Other authors and media personalities include CNN Chief White House correspondent and Anchor Jake Tapper, novelist and founding editor of The Believer Heidi Julavits, "Dean of rock critics" Robert Christgau, National Book Award winners Louise Erdrich and Phil Klay, novelist/screenwriter Budd Schulberg, political commentator Dinesh D'Souza, radio talk show host Laura Ingraham, commentator Mort Kondracke, and journalist James Panero. Norman Maclean, professor at the University of Chicago and author of A River Runs Through It and Other Stories, graduated from Dartmouth in 1924. Theodor Geisel, better known as children's author Dr. Seuss, was a member of the class of 1925. In the area of religion and theology, Dartmouth alumni include priests and ministers Ebenezer Porter, Jonathan Clarkson Gibbs, Caleb Sprague Henry, Arthur Whipple Jenks, Solomon Spalding, and Joseph Tracy; and rabbis Marshall Meyer, Arnold Resnicoff, and David E. Stern. Hyrum Smith, brother of Mormon Prophet Joseph Smith, attended the college in his teens. He was Patriarch of the LDS Church. Dartmouth alumni in academia include Stuart Kauffman and Jeffrey Weeks, both recipients of MacArthur Fellowships (commonly called "genius grants"). Dartmouth has also graduated three Nobel Prize winners: Owen Chamberlain (Physics, 1959), K. Barry Sharpless (Chemistry, 2001), and George Davis Snell (Physiology or Medicine, 1980). Educators include founder and first president of Bates College Oren Burbank Cheney (1839); the current chancellor of the University of California, San Diego, Marye Anne Fox (PhD. in Chemistry, 1974); founding president of Vassar College Milo Parker Jewett; founder and first president of Kenyon College Philander Chase; first professor of Wabash College Caleb Mills; president of Union College Charles Augustus Aiken. Nine of Dartmouth's 17 presidents were alumni of the college. Dartmouth alumni serving as CEOs or company presidents and executives include Charles Alfred Pillsbury, founder of the Pillsbury Company and patriarch of the Pillsbury family, Sandy Alderson (San Diego Padres), John Donahoe (eBay), Louis V. Gerstner, Jr. (IBM), Charles E. Haldeman (Putnam Investments), Donald J. Hall Sr. (Hallmark Cards), Douglas Hodge (CEO of PIMCO accused of fraud), Jeffrey R. Immelt (General Electric), Gail Koziara Boudreaux (United Health Care), Grant Tinker (NBC), and Brian Goldner (Hasbro). In film, entertainment, and television, Dartmouth is represented by David Benioff, co-creator, showrunner, and writer of Game of Thrones; Shonda Rhimes, creator of Grey's Anatomy, Private Practice and Scandal; Budd Schulberg, Academy Award-winning screenwriter of On the Waterfront; Michael Phillips, who won the Academy Award for best picture as co-producer of The Sting; Rachel Dratch, a former cast member of Saturday Night Live; Chris Meledandri, executive producer of Ice Age, Horton Hears a Who!, and Despicable Me; writer and director duo Phil Lord and Chris Miller; and the title character of Mister Rogers' Neighborhood, Fred Rogers.
Sir Walter Raleigh. Greenway was later the home of Dame Agatha Christie. In 1592 the Madre de Deus, a Portuguese treasure ship captured by the English in the Azores, docked at Dartmouth Harbour. It attracted all manner of traders, dealers, cutpurses and thieves and by the time Sir Walter Raleigh arrived to reclaim the Crown's share of the loot, a cargo estimated at half a million pounds had been reduced to £140,000. Still, ten freighters were needed to carry the treasure to London. Henry Hudson put into Dartmouth on his return from North America, and was arrested for sailing under a foreign flag. The Pilgrim Fathers put into Dartmouth's Bayard's Cove, en route from Southampton to America. They rested a while before setting off on their journey in the Mayflower and the Speedwell on 20 August 1620. About 300 miles west of Land's End, upon realising that the Speedwell was unseaworthy, it returned to Plymouth. The Mayflower departed alone to complete the crossing to Cape Cod. Dartmouth's sister city is Dartmouth, Massachusetts. The town contains many medieval and Elizabethan streetscapes and is a patchwork of narrow lanes and stone stairways. A significant number of the historic buildings are listed. One of the most obvious is the Butterwalk, built 1635 to 1640. Its intricately carved wooden fascia is supported on granite columns. Charles II held court in the Butterwalk whilst sheltering from storms in 1671 in a room which now forms part of Dartmouth Museum. Much of the interior survives from that time. The Royal Castle Hotel was built in 1639 on the then new quay. The building was re-fronted in the 19th century, and as the new frontage is itself listed, it is not possible to see the original which lies beneath. A claimant for the oldest building is a former merchant's house in Higher Street, now a Good Beer Guide listed public house called the Cherub, built circa 1380. Agincourt House (next to the Lower Ferry) is also 14th century. The remains of a fort at Gallants Bower just outside the town are some of the best preserved remains of a Civil War defensive structure. The fort was built by Royalist occupation forces in c. 1643 to the south east of the town, with a similar fort at Mount Ridley on the opposite slopes of what is now Kingswear. The Parliamentarian General Fairfax attacked from the north in 1646, taking the town and forcing the Royalists to surrender, after which Gallants Bower was demolished. 19th century Before 1671, what is now the town centre was almost entirely tidal mud flats. The New Road (now Victoria Road) was constructed across the bed of the (silted up) Mill Pool and up the Ford valley after 1823. Spithead was extended in 1864 when the Dartmouth and Torbay Railway arrived in Kingswear and a pontoon was constructed, linked to Spithead by a bridge. The railway directors and others formed the Dartmouth Harbour Commissioners. At this time, all the roads in those parts of Dartmouth which were not land reclamations were very narrow. In 1864-7 Higher Street was widened into Southtown and linked to Lower Street, which was also widened, with the northern part renamed Fairfax Place. Some of the buildings were rebuilt further back with decorative frontages. In 1881 the Harbour Commissioners produced a scheme for an embankment or esplanade from near the Lower Ferry to Hardness, across the remains of The Pool, to provide an attraction for tourists and further mooring space. It was completed in 1885 after much disagreement between the Borough, the Commissioners and the Railway (now the Great Western Railway). A new station was also built at this time. The building of the Embankment left a section of river isolated between Spithead and the New Ground, which is known as The Boatfloat, and is linked to the river by a bridge for small vessels under the road. The coming of steam ships led to Dartmouth being used as a bunkering port, with coal being brought in by ship or train. Coal lumpers were members of gangs, who competed to bunker the ships by racing to be first to a ship. This led to the men living as close as possible to the river, and their tenements became grossly overcrowded, with the families living in slum conditions, with up to 15 families in one house, one family to a room. The Royal National Lifeboat Institution opened the Dart Lifeboat Station at the Sand Quay in 1878, but it was closed in 1896. In all this time only one effective rescue was made by the lifeboat. 20th century The area to the north of Ridge Hill was a shallow and muddy bay ("Coombe Mud") with a narrow road running along the shore linking with the Higher Ferry. The mud was a dumping ground for vessels, including a submarine. The reclamation was completed in 1937 by the extension of the Embankment and the reclamation of the mud behind it, which became Coronation Park. In the 1920s, aided by government grants, the council made a start on clearing the slums. This was aided by the decline in the use of coal as a fuel for ships. The slums were demolished, and the inhabitants were rehoused in new houses in the Britannia Avenue area, to the west of the old village or hamlet of Townstal. The process was interrupted by the second world war, but was resumed with the construction of many prefabs, and later more houses. Community facilities were minimal at first, but a central area was reserved for a church, which was used by the Baptists and opened in 1954, together with a speedway track. The latter was later used for housing, but a new community centre was opened nearby, together with a leisure centre, an outdoor swimming pool, and later an indoor pool, and supermarkets. There are also light industrial units. In the latter part of the Second World War the town was a base for American forces and one of the departure points for Utah Beach in the D Day landings. Slipways and harbour improvements were also constructed. Much of the surrounding countryside and notably Slapton Sands was closed to the public while it was used by US troops for practise landings and manoeuvres. Between 1985 and 1990 the Embankment was widened by 6 metres and raised to prevent flooding at spring tides. A tidal lock gate was provided at the Boatfloat bridge, which could be closed at such times. 21st century Dart Lifeboat Station was reopened in 2007, the first time that a lifeboat had been stationed in the town since 1896. It has initially been kept in a temporary building in Coronation Park. In 2010, a fire seriously damaged numerous historical properties in Fairfax Place and Higher Street. Several were Tudor and Grade I or Grade II listed buildings. Governance The town was an ancient borough, incorporated by Edward III, known formally as Clifton-Dartmouth-Hardness, and consisting of the three parishes of St Petrox, St Saviour and Townstal, and incorporating the hamlets of Ford, Old Mill and Norton. It was reformed under the Municipal Corporations Act 1835. The town returned two members of parliament from the 13th century until 1835, after which one Member of Parliament (MP) was elected until the town was disenfranchised in 1868. It remained a municipal borough until 1974, when it was merged into the South Hams district, and became a successor parish of Dartmouth with a town council. Dartmouth Town Council is the lowest of three tiers of local government. It consists of 16 councillors representing the two wards of Clifton and Townstal. At the second tier, Dartmouth forms part of the Dartmouth and Kingswear ward of South Hams District Council, which returns three councillors. At the	Cherub, built circa 1380. Agincourt House (next to the Lower Ferry) is also 14th century. The remains of a fort at Gallants Bower just outside the town are some of the best preserved remains of a Civil War defensive structure. The fort was built by Royalist occupation forces in c. 1643 to the south east of the town, with a similar fort at Mount Ridley on the opposite slopes of what is now Kingswear. The Parliamentarian General Fairfax attacked from the north in 1646, taking the town and forcing the Royalists to surrender, after which Gallants Bower was demolished. 19th century Before 1671, what is now the town centre was almost entirely tidal mud flats. The New Road (now Victoria Road) was constructed across the bed of the (silted up) Mill Pool and up the Ford valley after 1823. Spithead was extended in 1864 when the Dartmouth and Torbay Railway arrived in Kingswear and a pontoon was constructed, linked to Spithead by a bridge. The railway directors and others formed the Dartmouth Harbour Commissioners. At this time, all the roads in those parts of Dartmouth which were not land reclamations were very narrow. In 1864-7 Higher Street was widened into Southtown and linked to Lower Street, which was also widened, with the northern part renamed Fairfax Place. Some of the buildings were rebuilt further back with decorative frontages. In 1881 the Harbour Commissioners produced a scheme for an embankment or esplanade from near the Lower Ferry to Hardness, across the remains of The Pool, to provide an attraction for tourists and further mooring space. It was completed in 1885 after much disagreement between the Borough, the Commissioners and the Railway (now the Great Western Railway). A new station was also built at this time. The building of the Embankment left a section of river isolated between Spithead and the New Ground, which is known as The Boatfloat, and is linked to the river by a bridge for small vessels under the road. The coming of steam ships led to Dartmouth being used as a bunkering port, with coal being brought in by ship or train. Coal lumpers were members of gangs, who competed to bunker the ships by racing to be first to a ship. This led to the men living as close as possible to the river, and their tenements became grossly overcrowded, with the families living in slum conditions, with up to 15 families in one house, one family to a room. The Royal National Lifeboat Institution opened the Dart Lifeboat Station at the Sand Quay in 1878, but it was closed in 1896. In all this time only one effective rescue was made by the lifeboat. 20th century The area to the north of Ridge Hill was a shallow and muddy bay ("Coombe Mud") with a narrow road running along the shore linking with the Higher Ferry. The mud was a dumping ground for vessels, including a submarine. The reclamation was completed in 1937 by the extension of the Embankment and the reclamation of the mud behind it, which became Coronation Park. In the 1920s, aided by government grants, the council made a start on clearing the slums. This was aided by the decline in the use of coal as a fuel for ships. The slums were demolished, and the inhabitants were rehoused in new houses in the Britannia Avenue area, to the west of the old village or hamlet of Townstal. The process was interrupted by the second world war, but was resumed with the construction of many prefabs, and later more houses. Community facilities were minimal at first, but a central area was reserved for a church, which was used by the Baptists and opened in 1954, together with a speedway track. The latter was later used for housing, but a new community centre was opened nearby, together with a leisure centre, an outdoor swimming pool, and later an indoor pool, and supermarkets. There are also light industrial units. In the latter part of the Second World War the town was a base for American forces and one of the departure points for Utah Beach in the D Day landings. Slipways and harbour improvements were also constructed. Much of the surrounding countryside and notably Slapton Sands was closed to the public while it was used by US troops for practise landings and manoeuvres. Between 1985 and 1990 the Embankment was widened by 6 metres and raised to prevent flooding at spring tides. A tidal lock gate was provided at the Boatfloat bridge, which could be closed at such times. 21st century Dart Lifeboat Station was reopened in 2007, the first time that a lifeboat had been stationed in the town since 1896. It has initially been kept in a temporary building in Coronation Park. In 2010, a fire seriously damaged numerous historical properties in Fairfax Place and Higher Street. Several were Tudor and Grade I or Grade II listed buildings. Governance The town was an ancient borough, incorporated by Edward III, known formally as Clifton-Dartmouth-Hardness, and consisting of the three parishes of St Petrox, St Saviour and Townstal, and incorporating the hamlets of Ford, Old Mill and Norton. It was reformed under the Municipal Corporations Act 1835. The town returned two members of parliament from the 13th century until 1835, after which one Member of Parliament (MP) was elected until the town was disenfranchised in 1868. It remained a municipal borough until 1974, when it was merged into the South Hams district, and became a successor parish of Dartmouth with a town council. Dartmouth Town Council is the lowest of three tiers of local government. It consists of 16 councillors representing the two wards of Clifton and Townstal. At the second tier, Dartmouth forms part of the Dartmouth and Kingswear ward of South Hams District Council, which returns three councillors. At the upper tier of local government Dartmouth and Kingswear Electoral Division elects one member to Devon County Council. Culture and tourism The Port of Dartmouth Royal Regatta takes place annually over three days at the end of August. The event sees the traditional regatta boat races along with markets, fun fairs, community games, musical performances, air displays including the Red Arrows and fireworks. A Royal Navy guard ship is often present at the event. Other cultural events include beer festivals in February and July (the latter in Kingswear), a music festival and an art and craft weekend in June, a food festival in October and a Christmas candlelit event. The Flavel Centre incorporates the public library and performance spaces, featuring films, live music and comedy and exhibitions. Bayard's Cove has been used in several television productions, including The Onedin Line a popular BBC television drama series that ran from 1971 to 1980. Many of the scenes from the BBC's popular series 'Down to Earth', starring Ricky Tomlinson, were filmed at various locations around the town. Notable tourist attractions include the Dartmouth Royal Naval College, Bayard's Cove Fort, Dartmouth Castle and the Dartmouth Steam Railway which terminates at Kingswear on the opposite bank of the river. Boat cruises to nearby places along the coast (such as Torbay and Start Bay) and up the river (to Totnes, Dittisham and the Greenway Estate) are provided by several companies. The paddlesteamer PS Kingswear Castle returned to the town in 2013. The South West Coast Path National Trail passes through the town, and also through extensive National Trust coastal properties at Little Dartmouth and Brownstone (Kingswear). The Dart Valley Trail starts in Dartmouth, with routes either side of the River Dart as far as Dittisham, and continuing to Totnes via Cornworthy, Tuckenhay and Ashprington. The area has long been well regarded for yachting, and there are extensive marinas at Sandquay, Kingswear and Noss (approximately one mile north of Kingswear). Climate The nearest Met Office weather station is Slapton, about 5 miles south-south west of Dartmouth and a similar distance from the coast. As with the rest of the British Isles and South West England, the area experiences a maritime climate with warm summers and mild winters—this is particularly pronounced due to its position near the coast—extremes range from a record low of just in January 1987 up to a record high of during June 1976. Transport Dartmouth is linked to Kingswear, on the other side of the River Dart, by three ferries. The Higher Ferry and the Lower Ferry are both vehicular ferries. The Passenger Ferry, as its name suggests, carries only passengers, principally to connect with the Dartmouth Steam Railway at Kingswear railway station. The nearest bridge across the Dart is in Totnes, some away by road. The A379 road runs through Dartmouth, linking the town to Slapton
the vomer and septum of the nostrils, and it shared details in the mandible, the zygomatic bone, the palate, and the hallux. The dodo differed from other pigeons mainly in the small size of the wings and the large size of the beak in proportion to the rest of the cranium. Throughout the 19th century, several species were classified as congeneric with the dodo, including the Rodrigues solitaire and the Réunion solitaire, as Didus solitarius and Raphus solitarius, respectively (Didus and Raphus being names for the dodo genus used by different authors of the time). An atypical 17th-century description of a dodo and bones found on Rodrigues, now known to have belonged to the Rodrigues solitaire, led Abraham Dee Bartlett to name a new species, Didus nazarenus, in 1852. Based on solitaire remains, it is now a synonym of that species. Crude drawings of the red rail of Mauritius were also misinterpreted as dodo species; Didus broeckii and Didus herberti. For many years the dodo and the Rodrigues solitaire were placed in a family of their own, the Raphidae (formerly Dididae), because their exact relationships with other pigeons were unresolved. Each was also placed in its own monotypic family (Raphidae and Pezophapidae, respectively), as it was thought that they had evolved their similarities independently. Osteological and DNA analysis has since led to the dissolution of the family Raphidae, and the dodo and solitaire are now placed in their own subfamily, Raphinae, within the family Columbidae. Evolution In 2002, American geneticist Beth Shapiro and colleagues analysed the DNA of the dodo for the first time. Comparison of mitochondrial cytochrome b and 12S rRNA sequences isolated from a tarsal of the Oxford specimen and a femur of a Rodrigues solitaire confirmed their close relationship and their placement within the Columbidae. The genetic evidence was interpreted as showing the Southeast Asian Nicobar pigeon (Caloenas nicobarica) to be their closest living relative, followed by the crowned pigeons (Goura) of New Guinea, and the superficially dodo-like tooth-billed pigeon (Didunculus strigirostris) from Samoa (its scientific name refers to its dodo-like beak). This clade consists of generally ground-dwelling island endemic pigeons. The following cladogram shows the dodo's closest relationships within the Columbidae, based on Shapiro et al., 2002: A similar cladogram was published in 2007, inverting the placement of Goura and Didunculus and including the pheasant pigeon (Otidiphaps nobilis) and the thick-billed ground pigeon (Trugon terrestris) at the base of the clade. The DNA used in these studies was obtained from the Oxford specimen, and since this material is degraded, and no usable DNA has been extracted from subfossil remains, these findings still need to be independently verified. Based on behavioural and morphological evidence, Jolyon C. Parish proposed that the dodo and Rodrigues solitaire should be placed in the subfamily Gourinae along with the Goura pigeons and others, in agreement with the genetic evidence. In 2014, DNA of the only known specimen of the recently extinct spotted green pigeon (Caloenas maculata) was analysed, and it was found to be a close relative of the Nicobar pigeon, and thus also the dodo and Rodrigues solitaire. The 2002 study indicated that the ancestors of the dodo and the solitaire diverged around the Paleogene-Neogene boundary, about 23.03 million years ago. The Mascarene Islands (Mauritius, Réunion, and Rodrigues), are of volcanic origin and are less than 10 million years old. Therefore, the ancestors of both birds probably remained capable of flight for a considerable time after the separation of their lineage. The Nicobar and spotted green pigeon were placed at the base of a lineage leading to the Raphinae, which indicates the flightless raphines had ancestors that were able to fly, were semi-terrestrial, and inhabited islands. This in turn supports the hypothesis that the ancestors of those birds reached the Mascarene islands by island hopping from South Asia. The lack of mammalian herbivores competing for resources on these islands allowed the solitaire and the dodo to attain very large sizes and flightlessness. Despite its divergent skull morphology and adaptations for larger size, many features of its skeleton remained similar to those of smaller, flying pigeons. Another large, flightless pigeon, the Viti Levu giant pigeon (Natunaornis gigoura), was described in 2001 from subfossil material from Fiji. It was only slightly smaller than the dodo and the solitaire, and it too is thought to have been related to the crowned pigeons. Etymology One of the original names for the dodo was the Dutch "Walghvoghel", first used in the journal of Dutch Vice Admiral Wybrand van Warwijck, who visited Mauritius during the Second Dutch Expedition to Indonesia in 1598. Walghe means "tasteless", "insipid", or "sickly", and means "bird". The name was translated by Jakob Friedlib into German as Walchstök or Walchvögel. The original Dutch report titled Waarachtige Beschryving was lost, but the English translation survived: Another account from that voyage, perhaps the first to mention the dodo, states that the Portuguese referred to them as penguins. The meaning may not have been derived from penguin (the Portuguese referred to those birds as "fotilicaios" at the time), but from pinion, a reference to the small wings. The crew of the Dutch ship Gelderland referred to the bird as "Dronte" (meaning "swollen") in 1602, a name that is still used in some languages. This crew also called them "griff-eendt" and "kermisgans", in reference to fowl fattened for the Kermesse festival in Amsterdam, which was held the day after they anchored on Mauritius. The etymology of the word dodo is unclear. Some ascribe it to the Dutch word dodoor for "sluggard", but it is more probably related to Dodaars, which means either "fat-arse" or "knot-arse", referring to the knot of feathers on the hind end. The first record of the word Dodaars is in Captain Willem Van West-Zanen's journal in 1602. The English writer Sir Thomas Herbert was the first to use the word dodo in print in his 1634 travelogue claiming it was referred to as such by the Portuguese, who had visited Mauritius in 1507. Another Englishman, Emmanuel Altham, had used the word in a 1628 letter in which he also claimed its origin was Portuguese. The name "dodar" was introduced into English at the same time as dodo, but was only used until the 18th century. As far as is known, the Portuguese never mentioned the bird. Nevertheless, some sources still state that the word dodo derives from the Portuguese word doudo (currently doido), meaning "fool" or "crazy". It has also been suggested that dodo was an onomatopoeic approximation of the bird's call, a two-note pigeon-like sound resembling "doo-doo". The Latin name cucullatus ("hooded") was first used by Juan Eusebio Nieremberg in 1635 as Cygnus cucullatus, in reference to Carolus Clusius's 1605 depiction of a dodo. In his 18th-century classic work Systema Naturae, Carl Linnaeus used cucullatus as the specific name, but combined it with the genus name Struthio (ostrich). Mathurin Jacques Brisson coined the genus name Raphus (referring to the bustards) in 1760, resulting in the current name Raphus cucullatus. In 1766, Linnaeus coined the new binomial Didus ineptus (meaning "inept dodo"). This has become a synonym of the earlier name because of nomenclatural priority. Description As no complete dodo specimens exist, its external appearance, such as plumage and colouration, is hard to determine. Illustrations and written accounts of encounters with the dodo between its discovery and its extinction (1598–1662) are the primary evidence for its external appearance. According to most representations, the dodo had greyish or brownish plumage, with lighter primary feathers and a tuft of curly light feathers high on its rear end. The head was grey and naked, the beak green, black and yellow, and the legs were stout and yellowish, with black claws. A study of the few remaining feathers on the Oxford specimen head showed that they were pennaceous rather than plumaceous (downy) and most similar to those of other pigeons. Subfossil remains and remnants of the birds that were brought to Europe in the 17th century show that dodos were very large birds, up to tall. The bird was sexually dimorphic; males were larger and had proportionally longer beaks. Weight estimates have varied from study to study. In 1993, Bradley C. Livezey proposed that males would have weighed and females . Also in 1993, Andrew C. Kitchener attributed a high contemporary weight estimate and the roundness of dodos depicted in Europe to these birds having been overfed in captivity; weights in the wild were estimated to have been in the range of , and fattened birds could have weighed . A 2011 estimate by Angst and colleagues gave an average weight as low as . This has also been questioned, and there is still controversy over weight estimates. A 2016 study estimated the weight at , based on CT scans of composite skeletons. It has also been suggested that the weight depended on the season, and that individuals were fat during cool seasons, but less so during hot. The skull of the dodo differed much from those of other pigeons, especially in being more robust, the bill having a hooked tip, and in having a short cranium compared to the jaws. The upper bill was nearly twice as long as the cranium, which was short compared to those of its closest pigeon relatives. The openings of the bony nostrils were elongated along the length of the beak, and they contained no bony septum. The cranium (excluding the beak) was wider than it was long, and the frontal bone formed a dome-shape, with the highest point above the hind part of the eye sockets. The skull sloped downwards at the back. The eye sockets occupied much of the hind part of the skull. The sclerotic rings inside the eye were formed by eleven ossicles (small bones), similar to the amount in other pigeons. The mandible was slightly curved, and each half had a single fenestra (opening), as in other pigeons. The dodo had about nineteen presynsacral vertebrae (those of the neck and thorax, including three fused into a notarium), sixteen synsacral vertebrae (those of the lumbar region and sacrum), six free tail (caudal) vertebrae, and a pygostyle. The neck had well-developed areas for muscle and ligament attachment, probably to support the heavy skull and beak. On each side, it had six ribs, four of which articulated with the sternum through sternal ribs. The sternum was large, but small in relation to the body compared to those of much smaller pigeons that are able to fly. The sternum was highly pneumatic, broad, and relatively thick in cross-section. The bones of the pectoral girdle, shoulder blades, and wing bones were reduced in size compared to those of flighted pigeon, and were more gracile compared to those of the Rodrigues solitaire, but none of the individual skeletal components had disappeared. The carpometacarpus of the dodo was more robust than that of the solitaire, however. The pelvis was wider than that of the solitaire and other relatives, yet was comparable to the proportions in some smaller, flighted pigeons. Most of the leg bones were more robust than those of extant pigeons and the solitaire, but the length proportions were little different. Many of the skeletal features that distinguish the dodo and the Rodrigues solitaire, its closest relative, from other pigeons have been attributed to their flightlessness. The pelvic elements were thicker than those of flighted pigeons to support the higher weight, and the pectoral region and the small wings were paedomorphic, meaning that they were underdeveloped and retained juvenile features. The skull, trunk and pelvic limbs were peramorphic, meaning that they changed considerably with age. The dodo shared several other traits with the Rodrigues solitaire, such as features of the skull, pelvis, and sternum, as well as their large size. It differed in other aspects, such as being more robust and shorter than the solitaire, having a larger skull and beak, a rounded skull roof, and smaller orbits. The dodo's neck and legs were proportionally shorter, and it did not possess an equivalent to the knob present on the solitaire's wrists. Contemporary descriptions Most contemporary descriptions of the dodo are found in ship's logs and journals of the Dutch East India Company vessels that docked in Mauritius when the Dutch Empire ruled the island. These records were used as guides for future voyages. Few contemporary accounts are reliable, as many seem to be based on earlier accounts, and none were written by scientists. One of the earliest accounts, from van Warwijck's 1598 journal, describes the bird as follows: One of the most detailed descriptions is by Herbert in A Relation of Some Yeares Travaille into Afrique and the Greater Asia from 1634: Contemporary depictions The travel journal of the Dutch ship Gelderland (1601–1603), rediscovered in the 1860s, contains the only known sketches of living or recently killed specimens drawn on Mauritius. They have been attributed to the professional artist Joris Joostensz Laerle, who also drew other now-extinct Mauritian birds, and to a second, less refined artist. Apart from these sketches, it is unknown how many of the twenty or so 17th-century illustrations of the dodos were drawn from life or from stuffed specimens, which affects their reliability. Since dodos are otherwise only known from limited physical remains and descriptions, contemporary artworks are important to reconstruct their appearance in life. While there has been an effort since the mid-19 century to list all historical illustrations of dodos, previously unknown depictions continue to be discovered occasionally. The traditional image of the dodo is of a very fat and clumsy bird, but this view may be exaggerated. The general opinion of scientists today is that many old European depictions were based on overfed captive birds or crudely stuffed specimens. It has also been suggested that the images might show dodos with puffed feathers, as part of display behaviour. The Dutch painter Roelant Savery was the most prolific and influential illustrator of the dodo, having made at least twelve depictions, often showing it in the lower corners. A famous painting of his from 1626, now called Edwards's Dodo as it was once owned by the ornithologist George Edwards, has since become the standard image of a dodo. It is housed in the Natural History Museum, London. The image shows a particularly fat bird and is the source for many other dodo illustrations. An Indian Mughal painting rediscovered in the Hermitage Museum, St. Petersburg, in 1955 shows a dodo along with native Indian birds. It depicts a slimmer, brownish bird, and its discoverer Aleksander Iwanow and British palaeontologist Julian Hume regarded it as one of the most accurate depictions of the living dodo; the surrounding birds are clearly identifiable and depicted with appropriate colouring. It is believed to be from the 17th century and has been attributed to the Mughal painter Ustad Mansur. The bird depicted probably lived in the menagerie of the Mughal Emperor Jahangir, located in Surat, where the English traveller Peter Mundy also claimed to have seen two dodos sometime between 1628 and 1633. In 2014, another Indian illustration of a dodo was reported, but it was found to be derivative of an 1836 German illustration. All post-1638 depictions appear to be based on earlier images, around the time reports mentioning dodos became rarer. Differences in the depictions led ornithologists such as Anthonie Cornelis Oudemans and Masauji Hachisuka to speculate about sexual dimorphism, ontogenic traits, seasonal variation, and even the existence of different species, but these theories are not accepted today. Because details such as markings of the beak, the form of the tail feathers, and colouration vary from account to account, it is impossible to determine the exact morphology of these features, whether they signal age or sex, or if they even reflect reality. Hume argued that the nostrils of the living dodo would have been slits, as seen in the Gelderland, Cornelis Saftleven, Savery's Crocker Art Gallery, and Ustad Mansur images. According to this claim, the gaping nostrils often seen in paintings indicate that taxidermy specimens were used as models. Most depictions show that the wings were held in an extended position, unlike flighted pigeons, but similar to ratites such as the ostrich and kiwi. Behaviour and ecology Little is known of the behaviour of the dodo, as most contemporary descriptions are very brief. Based on weight estimates, it has been suggested the male could reach the age of 21, and the female 17. Studies of the cantilever strength of its leg bones indicate that it could run quite fast. The legs were robust and strong to support the bulk of the bird, and also made it agile and manoeuvrable in the dense, pre-human landscape. Though the wings were small, well-developed muscle scars on the bones show that they were not completely vestigial, and may have been used for display behaviour and balance; extant pigeons also use their wings for such purposes. Unlike the Rodrigues solitaire, there is no evidence that the dodo used its wings in intraspecific combat. Though some dodo bones have been found with healed fractures, it had weak pectoral muscles and more reduced wings in comparison. The dodo may instead have used its large, hooked beak in territorial disputes. Since Mauritius receives more rainfall and has less seasonal variation than Rodrigues, which would have affected the availability of resources on the island, the dodo would have less reason to evolve aggressive territorial behaviour. The Rodrigues solitaire was therefore probably the more aggressive of the two. In 2016, the first 3D endocast was made from the brain of the dodo; the brain-to-body-size ratio was similar to that of modern pigeons, indicating that dodos were probably equal in intelligence. The preferred habitat of the dodo is unknown, but old descriptions suggest that it inhabited the woods on the drier coastal areas of south and west Mauritius. This view is supported by the fact that the Mare aux Songes swamp, where most dodo remains have been excavated, is close to the sea in south-eastern Mauritius. Such a limited distribution across the island could well have contributed to its extinction. A 1601 map from the Gelderland journal shows a small island off the coast of Mauritius where dodos were caught. Julian Hume has suggested this island was l'île aux Benitiers in Tamarin Bay, on the west coast of Mauritius. Subfossil bones have also been found inside caves in highland areas, indicating that it once occurred on mountains. Work at the Mare aux Songes swamp has shown that its habitat was dominated by tambalacoque and Pandanus trees and endemic palms. The near-coastal placement and wetness of the Mare aux Songes led to a high diversity of plant species, whereas the surrounding areas were drier. Many endemic species of Mauritius became extinct after the arrival of humans, so the ecosystem of the island is badly damaged and hard to reconstruct. Before humans arrived, Mauritius was entirely covered in forests, but very little remains of them today, because of deforestation. The surviving endemic fauna is still seriously threatened. The dodo lived alongside other recently extinct Mauritian birds such as the flightless red rail, the broad-billed parrot, the Mascarene grey parakeet, the Mauritius blue pigeon, the Mauritius owl, the Mascarene coot, the Mauritian shelduck, the Mauritian duck, and the Mauritius night heron. Extinct Mauritian reptiles include the saddle-backed Mauritius giant tortoise, the domed Mauritius giant tortoise, the Mauritian giant skink, and the Round Island burrowing boa. The small Mauritian flying fox and the snail Tropidophora carinata lived on Mauritius and Réunion, but vanished from both islands. Some plants, such as Casearia tinifolia and the palm orchid, have also become extinct. Diet A 1631 Dutch letter (long thought lost, but rediscovered in 2017) is the only account of the dodo's diet, and also mentions that it used its beak for defence. The document uses word-play to refer to the animals described, with dodos presumably being an allegory for wealthy mayors: In addition to fallen fruits, the dodo probably subsisted on nuts, seeds, bulbs, and roots. It has also been suggested that the dodo might have eaten crabs and shellfish, like their relatives the crowned pigeons. Its feeding habits must have been versatile, since captive specimens were probably given a wide range of food on the long sea journeys. Oudemans suggested that as Mauritius has marked dry and wet seasons, the dodo probably fattened itself on ripe fruits at the end of the wet season to survive the dry season, when food was scarce; contemporary reports describe the bird's "greedy" appetite. The Mauritian ornithologist France Staub suggested in 1996 that they mainly fed on palm fruits, and he attempted to correlate the fat-cycle of the dodo with the fruiting regime of the palms. Skeletal elements of the upper jaw appear to have been rhynchokinetic (movable in relation to each other), which must have affected its feeding behaviour. In extant birds, such as frugivorous (fruit-eating) pigeons, kinetic premaxillae help with consuming large food items. The beak also appears to have been able to withstand high force loads, which indicates a diet of hard food. Examination of the brain endocast found that though the brain was similar to that of other pigeons in most respects, the dodo had a comparatively large olfactory bulb. This gave the dodo a good sense of smell, which may have aided in locating fruit and small prey. Several contemporary sources state that the dodo used Gastroliths (gizzard stones) to aid digestion. The English writer Sir Hamon L'Estrange witnessed a live bird in London and described it as follows: It is not known how the young were fed, but related pigeons provide crop milk. Contemporary depictions show a large crop, which was probably used to add space for food storage and to produce crop milk. It has been suggested that the maximum size attained by the dodo and the solitaire was limited by the amount of crop milk they could produce for their young during early growth. In 1973, the tambalacoque, also known as the dodo tree, was thought to be dying out on Mauritius, to which it is endemic. There were supposedly only 13 specimens left, all estimated to be about 300 years old. Stanley Temple hypothesised that it depended on the dodo for its propagation, and that its seeds would germinate only after passing through the bird's digestive tract. He claimed that the tambalacoque was now nearly coextinct because of the disappearance of the dodo. Temple overlooked reports from the 1940s that found that tambalacoque seeds germinated, albeit very rarely, without being abraded during digestion. Others have contested his hypothesis and suggested that the decline of the tree was exaggerated, or seeds were also distributed by other extinct animals such as Cylindraspis tortoises, fruit bats or the broad-billed parrot. According to Wendy Strahm and Anthony Cheke, two experts in the ecology of the Mascarene Islands, the tree, while rare, has germinated since the demise of the dodo and numbers several hundred, not 13 as claimed by Temple, hence discrediting Temple's view as to the dodo and the tree's sole survival relationship. The Brazilian ornithologist Carlos Yamashita suggested in 1997 that the broad-billed parrot may have depended on dodos and Cylindraspis tortoises to eat palm fruits and excrete their seeds, which became food for the parrots. Anodorhynchus macaws depended on now-extinct South American megafauna in the same way, but now rely on domesticated cattle for this service. Reproduction and development As it was flightless and terrestrial and there were no mammalian predators or other kinds of natural enemy on Mauritius, the dodo probably nested on the ground. The account by François Cauche from 1651 is the only description of the egg and the call: Cauche's account is problematic, since it also mentions that the bird he was describing had three toes and no tongue, unlike dodos. This led some to believe that Cauche was describing a new species of dodo ("Didus nazarenus"). The description was most probably mingled with that of a cassowary, and Cauche's writings have other inconsistencies. A mention of a "young ostrich" taken on board a ship in 1617 is the only other reference to a possible juvenile dodo. An egg claimed to be that of a dodo is stored in the East London Museum in South Africa. It was donated by the South African museum official Marjorie Courtenay-Latimer, whose great aunt had received it from a captain who claimed to have found it in a swamp on Mauritius. In 2010, the curator of the museum proposed using genetic studies to determine its authenticity. It may instead be an aberrant ostrich egg. Because of the possible single-egg clutch and the bird's large size, it has been proposed that the dodo was K-selected, meaning that it produced few altricial offspring, which required parental care until they matured. Some evidence, including the large size and the fact that tropical and frugivorous birds have slower growth rates, indicates that the bird may have had a protracted development period. The fact that no juvenile dodos have been found in the Mare aux Songes swamp may indicate that they produced little offspring, that they matured rapidly, that the breeding grounds were far away from the swamp, or that the risk of miring was seasonal. A 2017 study examined the histology of thin-sectioned dodo bones, modern Mauritian birds, local ecology, and contemporary accounts, to recover information about the life history of the dodo. The study suggested that dodos bred around August, after having potentially fattened themselves, corresponding with the fat and thin cycles of many vertebrates of Mauritius. The chicks grew rapidly, reaching robust, almost adult, sizes, and sexual maturity before Austral summer or the cyclone season. Adult dodos which had just bred moulted after Austral summer, around March. The feathers of the wings and tail were replaced first, and the moulting would have completed at the end of July, in time for the next breeding season. Different stages of moulting may also account for inconsistencies in contemporary descriptions of dodo plumage. Relationship with humans Mauritius had previously been visited by Arab vessels in the Middle Ages and Portuguese ships between 1507 and 1513, but was settled by neither. No records of dodos by these are known, although the Portuguese name for Mauritius, "Cerne (swan) Island", may have been a reference to dodos. The Dutch Empire acquired Mauritius in 1598, renaming it after Maurice of Nassau, and it was used for the provisioning of trade vessels of the Dutch East India Company henceforward. The earliest known accounts of the dodo were provided by Dutch travelers during the Second Dutch Expedition to Indonesia, led by admiral Jacob van Neck in 1598. They appear in reports published in 1601, which also contain the first published illustration of the bird. Since the first sailors to visit Mauritius had been at sea for a long time, their interest in these large birds was mainly culinary. The 1602 journal by Willem Van West-Zanen of the ship Bruin-Vis mentions that 24–25 dodos were hunted for food, which were so large that two could scarcely be consumed at mealtime, their remains being preserved by salting. An illustration made for the 1648 published version of this journal, showing the killing of dodos, a dugong, and possibly Mascarene grey parakeets, was captioned with a Dutch poem, here in Hugh Strickland's 1848 translation: Some early travellers found dodo meat unsavoury, and preferred to eat parrots and pigeons; others described it as tough but good. Some hunted dodos only for their gizzards, as this was considered the most delicious part of the bird. Dodos were easy to catch, but hunters had to be careful not to be bitten by their powerful beaks. The appearance of the dodo and the red rail led Peter Mundy to speculate, 230 years before Charles Darwin's theory of evolution: Dodos transported abroad The dodo was found interesting enough that living specimens were sent to Europe and the East. The number of transported dodos that reached their destinations alive is uncertain, and it is unknown how they relate to contemporary depictions and the few non-fossil remains in European museums. Based on a combination of contemporary accounts, paintings, and specimens, Julian Hume has inferred that at least eleven transported dodos reached their destinations alive. Hamon L'Estrange's description of a dodo that he saw in London in 1638 is the only account that specifically mentions a live specimen in Europe. In 1626 Adriaen van de Venne drew a dodo that he claimed to have seen in Amsterdam, but he did not mention if it were alive, and his depiction is reminiscent of Savery's Edwards's Dodo. Two live specimens were seen by Peter Mundy in Surat, India, between 1628 and 1634, one of which may have been the individual painted by Ustad Mansur around 1625. In 1628, Emmanuel Altham visited Mauritius and sent a letter to his brother in England: Whether the dodo survived the journey is unknown, and the letter was destroyed by fire in the 19th century. The earliest known picture of a dodo specimen in Europe is from a collection of paintings depicting animals in the royal menagerie of Emperor Rudolph II in Prague. This collection includes	such as markings of the beak, the form of the tail feathers, and colouration vary from account to account, it is impossible to determine the exact morphology of these features, whether they signal age or sex, or if they even reflect reality. Hume argued that the nostrils of the living dodo would have been slits, as seen in the Gelderland, Cornelis Saftleven, Savery's Crocker Art Gallery, and Ustad Mansur images. According to this claim, the gaping nostrils often seen in paintings indicate that taxidermy specimens were used as models. Most depictions show that the wings were held in an extended position, unlike flighted pigeons, but similar to ratites such as the ostrich and kiwi. Behaviour and ecology Little is known of the behaviour of the dodo, as most contemporary descriptions are very brief. Based on weight estimates, it has been suggested the male could reach the age of 21, and the female 17. Studies of the cantilever strength of its leg bones indicate that it could run quite fast. The legs were robust and strong to support the bulk of the bird, and also made it agile and manoeuvrable in the dense, pre-human landscape. Though the wings were small, well-developed muscle scars on the bones show that they were not completely vestigial, and may have been used for display behaviour and balance; extant pigeons also use their wings for such purposes. Unlike the Rodrigues solitaire, there is no evidence that the dodo used its wings in intraspecific combat. Though some dodo bones have been found with healed fractures, it had weak pectoral muscles and more reduced wings in comparison. The dodo may instead have used its large, hooked beak in territorial disputes. Since Mauritius receives more rainfall and has less seasonal variation than Rodrigues, which would have affected the availability of resources on the island, the dodo would have less reason to evolve aggressive territorial behaviour. The Rodrigues solitaire was therefore probably the more aggressive of the two. In 2016, the first 3D endocast was made from the brain of the dodo; the brain-to-body-size ratio was similar to that of modern pigeons, indicating that dodos were probably equal in intelligence. The preferred habitat of the dodo is unknown, but old descriptions suggest that it inhabited the woods on the drier coastal areas of south and west Mauritius. This view is supported by the fact that the Mare aux Songes swamp, where most dodo remains have been excavated, is close to the sea in south-eastern Mauritius. Such a limited distribution across the island could well have contributed to its extinction. A 1601 map from the Gelderland journal shows a small island off the coast of Mauritius where dodos were caught. Julian Hume has suggested this island was l'île aux Benitiers in Tamarin Bay, on the west coast of Mauritius. Subfossil bones have also been found inside caves in highland areas, indicating that it once occurred on mountains. Work at the Mare aux Songes swamp has shown that its habitat was dominated by tambalacoque and Pandanus trees and endemic palms. The near-coastal placement and wetness of the Mare aux Songes led to a high diversity of plant species, whereas the surrounding areas were drier. Many endemic species of Mauritius became extinct after the arrival of humans, so the ecosystem of the island is badly damaged and hard to reconstruct. Before humans arrived, Mauritius was entirely covered in forests, but very little remains of them today, because of deforestation. The surviving endemic fauna is still seriously threatened. The dodo lived alongside other recently extinct Mauritian birds such as the flightless red rail, the broad-billed parrot, the Mascarene grey parakeet, the Mauritius blue pigeon, the Mauritius owl, the Mascarene coot, the Mauritian shelduck, the Mauritian duck, and the Mauritius night heron. Extinct Mauritian reptiles include the saddle-backed Mauritius giant tortoise, the domed Mauritius giant tortoise, the Mauritian giant skink, and the Round Island burrowing boa. The small Mauritian flying fox and the snail Tropidophora carinata lived on Mauritius and Réunion, but vanished from both islands. Some plants, such as Casearia tinifolia and the palm orchid, have also become extinct. Diet A 1631 Dutch letter (long thought lost, but rediscovered in 2017) is the only account of the dodo's diet, and also mentions that it used its beak for defence. The document uses word-play to refer to the animals described, with dodos presumably being an allegory for wealthy mayors: In addition to fallen fruits, the dodo probably subsisted on nuts, seeds, bulbs, and roots. It has also been suggested that the dodo might have eaten crabs and shellfish, like their relatives the crowned pigeons. Its feeding habits must have been versatile, since captive specimens were probably given a wide range of food on the long sea journeys. Oudemans suggested that as Mauritius has marked dry and wet seasons, the dodo probably fattened itself on ripe fruits at the end of the wet season to survive the dry season, when food was scarce; contemporary reports describe the bird's "greedy" appetite. The Mauritian ornithologist France Staub suggested in 1996 that they mainly fed on palm fruits, and he attempted to correlate the fat-cycle of the dodo with the fruiting regime of the palms. Skeletal elements of the upper jaw appear to have been rhynchokinetic (movable in relation to each other), which must have affected its feeding behaviour. In extant birds, such as frugivorous (fruit-eating) pigeons, kinetic premaxillae help with consuming large food items. The beak also appears to have been able to withstand high force loads, which indicates a diet of hard food. Examination of the brain endocast found that though the brain was similar to that of other pigeons in most respects, the dodo had a comparatively large olfactory bulb. This gave the dodo a good sense of smell, which may have aided in locating fruit and small prey. Several contemporary sources state that the dodo used Gastroliths (gizzard stones) to aid digestion. The English writer Sir Hamon L'Estrange witnessed a live bird in London and described it as follows: It is not known how the young were fed, but related pigeons provide crop milk. Contemporary depictions show a large crop, which was probably used to add space for food storage and to produce crop milk. It has been suggested that the maximum size attained by the dodo and the solitaire was limited by the amount of crop milk they could produce for their young during early growth. In 1973, the tambalacoque, also known as the dodo tree, was thought to be dying out on Mauritius, to which it is endemic. There were supposedly only 13 specimens left, all estimated to be about 300 years old. Stanley Temple hypothesised that it depended on the dodo for its propagation, and that its seeds would germinate only after passing through the bird's digestive tract. He claimed that the tambalacoque was now nearly coextinct because of the disappearance of the dodo. Temple overlooked reports from the 1940s that found that tambalacoque seeds germinated, albeit very rarely, without being abraded during digestion. Others have contested his hypothesis and suggested that the decline of the tree was exaggerated, or seeds were also distributed by other extinct animals such as Cylindraspis tortoises, fruit bats or the broad-billed parrot. According to Wendy Strahm and Anthony Cheke, two experts in the ecology of the Mascarene Islands, the tree, while rare, has germinated since the demise of the dodo and numbers several hundred, not 13 as claimed by Temple, hence discrediting Temple's view as to the dodo and the tree's sole survival relationship. The Brazilian ornithologist Carlos Yamashita suggested in 1997 that the broad-billed parrot may have depended on dodos and Cylindraspis tortoises to eat palm fruits and excrete their seeds, which became food for the parrots. Anodorhynchus macaws depended on now-extinct South American megafauna in the same way, but now rely on domesticated cattle for this service. Reproduction and development As it was flightless and terrestrial and there were no mammalian predators or other kinds of natural enemy on Mauritius, the dodo probably nested on the ground. The account by François Cauche from 1651 is the only description of the egg and the call: Cauche's account is problematic, since it also mentions that the bird he was describing had three toes and no tongue, unlike dodos. This led some to believe that Cauche was describing a new species of dodo ("Didus nazarenus"). The description was most probably mingled with that of a cassowary, and Cauche's writings have other inconsistencies. A mention of a "young ostrich" taken on board a ship in 1617 is the only other reference to a possible juvenile dodo. An egg claimed to be that of a dodo is stored in the East London Museum in South Africa. It was donated by the South African museum official Marjorie Courtenay-Latimer, whose great aunt had received it from a captain who claimed to have found it in a swamp on Mauritius. In 2010, the curator of the museum proposed using genetic studies to determine its authenticity. It may instead be an aberrant ostrich egg. Because of the possible single-egg clutch and the bird's large size, it has been proposed that the dodo was K-selected, meaning that it produced few altricial offspring, which required parental care until they matured. Some evidence, including the large size and the fact that tropical and frugivorous birds have slower growth rates, indicates that the bird may have had a protracted development period. The fact that no juvenile dodos have been found in the Mare aux Songes swamp may indicate that they produced little offspring, that they matured rapidly, that the breeding grounds were far away from the swamp, or that the risk of miring was seasonal. A 2017 study examined the histology of thin-sectioned dodo bones, modern Mauritian birds, local ecology, and contemporary accounts, to recover information about the life history of the dodo. The study suggested that dodos bred around August, after having potentially fattened themselves, corresponding with the fat and thin cycles of many vertebrates of Mauritius. The chicks grew rapidly, reaching robust, almost adult, sizes, and sexual maturity before Austral summer or the cyclone season. Adult dodos which had just bred moulted after Austral summer, around March. The feathers of the wings and tail were replaced first, and the moulting would have completed at the end of July, in time for the next breeding season. Different stages of moulting may also account for inconsistencies in contemporary descriptions of dodo plumage. Relationship with humans Mauritius had previously been visited by Arab vessels in the Middle Ages and Portuguese ships between 1507 and 1513, but was settled by neither. No records of dodos by these are known, although the Portuguese name for Mauritius, "Cerne (swan) Island", may have been a reference to dodos. The Dutch Empire acquired Mauritius in 1598, renaming it after Maurice of Nassau, and it was used for the provisioning of trade vessels of the Dutch East India Company henceforward. The earliest known accounts of the dodo were provided by Dutch travelers during the Second Dutch Expedition to Indonesia, led by admiral Jacob van Neck in 1598. They appear in reports published in 1601, which also contain the first published illustration of the bird. Since the first sailors to visit Mauritius had been at sea for a long time, their interest in these large birds was mainly culinary. The 1602 journal by Willem Van West-Zanen of the ship Bruin-Vis mentions that 24–25 dodos were hunted for food, which were so large that two could scarcely be consumed at mealtime, their remains being preserved by salting. An illustration made for the 1648 published version of this journal, showing the killing of dodos, a dugong, and possibly Mascarene grey parakeets, was captioned with a Dutch poem, here in Hugh Strickland's 1848 translation: Some early travellers found dodo meat unsavoury, and preferred to eat parrots and pigeons; others described it as tough but good. Some hunted dodos only for their gizzards, as this was considered the most delicious part of the bird. Dodos were easy to catch, but hunters had to be careful not to be bitten by their powerful beaks. The appearance of the dodo and the red rail led Peter Mundy to speculate, 230 years before Charles Darwin's theory of evolution: Dodos transported abroad The dodo was found interesting enough that living specimens were sent to Europe and the East. The number of transported dodos that reached their destinations alive is uncertain, and it is unknown how they relate to contemporary depictions and the few non-fossil remains in European museums. Based on a combination of contemporary accounts, paintings, and specimens, Julian Hume has inferred that at least eleven transported dodos reached their destinations alive. Hamon L'Estrange's description of a dodo that he saw in London in 1638 is the only account that specifically mentions a live specimen in Europe. In 1626 Adriaen van de Venne drew a dodo that he claimed to have seen in Amsterdam, but he did not mention if it were alive, and his depiction is reminiscent of Savery's Edwards's Dodo. Two live specimens were seen by Peter Mundy in Surat, India, between 1628 and 1634, one of which may have been the individual painted by Ustad Mansur around 1625. In 1628, Emmanuel Altham visited Mauritius and sent a letter to his brother in England: Whether the dodo survived the journey is unknown, and the letter was destroyed by fire in the 19th century. The earliest known picture of a dodo specimen in Europe is from a collection of paintings depicting animals in the royal menagerie of Emperor Rudolph II in Prague. This collection includes paintings of other Mauritian animals as well, including a red rail. The dodo, which may be a juvenile, seems to have been dried or embalmed, and had probably lived in the emperor's zoo for a while together with the other animals. That whole stuffed dodos were present in Europe indicates they had been brought alive and died there; it is unlikely that taxidermists were on board the visiting ships, and spirits were not yet used to preserve biological specimens. Most tropical specimens were preserved as dried heads and feet. One dodo was reportedly sent as far as Nagasaki, Japan in 1647, but it was long unknown whether it arrived. Contemporary documents first published in 2014 proved the story, and showed that it had arrived alive. It was meant as a gift, and, despite its rarity, was considered of equal value to a white deer and a bezoar stone. It is the last recorded live dodo in captivity. Extinction Like many animals that evolved in isolation from significant predators, the dodo was entirely fearless of humans. This fearlessness and its inability to fly made the dodo easy prey for sailors. Although some scattered reports describe mass killings of dodos for ships' provisions, archaeological investigations have found scant evidence of human predation. Bones of at least two dodos were found in caves at Baie du Cap that sheltered fugitive slaves and convicts in the 17th century, which would not have been easily accessible to dodos because of the high, broken terrain. The human population on Mauritius (an area of ) never exceeded 50 people in the 17th century, but they introduced other animals, including dogs, pigs, cats, rats, and crab-eating macaques, which plundered dodo nests and competed for the limited food resources. At the same time, humans destroyed the forest habitat of the dodos. The impact of the introduced animals on the dodo population, especially the pigs and macaques, is today considered more severe than that of hunting. Rats were perhaps not much of a threat to the nests, since dodos would have been used to dealing with local land crabs. It has been suggested that the dodo may already have been rare or localised before the arrival of humans on Mauritius, since it would have been unlikely to become extinct so rapidly if it had occupied all the remote areas of the island. A 2005 expedition found subfossil remains of dodos and other animals killed by a flash flood. Such mass mortalities would have further jeopardised a species already in danger of becoming extinct. Yet the fact that the dodo survived hundreds of years of volcanic activity and climatic changes shows the bird was resilient within its ecosystem. Some controversy surrounds the date of its extinction. The last widely accepted record of a dodo sighting is the 1662 report by shipwrecked mariner Volkert Evertsz of the Dutch ship Arnhem, who described birds caught on a small islet off Mauritius, now suggested to be Amber Island: The dodos on this islet may not necessarily have been the last members of the species. The last claimed sighting of a dodo was reported in the hunting records of Isaac Johannes Lamotius in 1688. A 2003 statistical analysis of these records by the biologists David L. Roberts and Andrew R. Solow gave a new estimated extinction date of 1693, with a 95% confidence interval of 1688–1715. These authors also pointed out that because the last sighting before 1662 was in 1638, the dodo was probably already quite rare by the 1660s, and thus a disputed report from 1674 by an escaped slave could not be dismissed out of hand. The British ornithologist Alfred Newton suggested in 1868 that the name of the dodo was transferred to the red rail after the former had gone extinct. Cheke also pointed out that some descriptions after 1662 use the names "Dodo" and "Dodaers" when referring to the red rail, indicating that they had been transferred to it. He therefore pointed to the 1662 description as the last credible observation. A 1668 account by English traveller John Marshall, who used the names "Dodo" and "Red Hen" interchangeably for the red rail, mentioned that the meat was "hard", which echoes the description of the meat in the 1681 account. Even the 1662 account has been questioned by the writer Errol Fuller, as the reaction to distress cries matches what was described for the red rail. Until this explanation was proposed, a description of "dodos" from 1681 was thought to be the last account, and that date still has proponents. Cheke stated in 2014 that then recently accessible Dutch manuscripts indicate that no dodos were seen by settlers in 1664–1674. In 2020, Cheke and the British researcher Jolyon C. Parish suggested that all mentions of dodos after the mid-17th century instead referred to red rails, and that the dodo had disappeared due to predation by feral pigs during a hiatus in settlement of Mauritius (1658–1664). The dodo's extinction therefore was not realised at the time, since new settlers had not seen real dodos, but as they expected to see flightless birds, they referred to the red rail by that name instead. Since red rails probably had larger clutches than dodos and their eggs could be incubated faster, and their nests were perhaps concealed, they probably bred more efficiently, and were less vulnerable to pigs. It is unlikely the issue will ever be resolved, unless late reports mentioning the name alongside a physical description are rediscovered. The IUCN Red List accepts Cheke's rationale for choosing the 1662 date, taking all subsequent reports to refer to red rails. In any case, the dodo was probably extinct by 1700, about a century after its discovery in 1598. The Dutch left Mauritius in 1710, but by then the dodo and most of the large terrestrial vertebrates there had become extinct. Even though the rareness of the dodo was reported already in the 17th century, its extinction was not recognised until the 19th century. This was partly because, for religious reasons, extinction was not believed possible until later proved so by Georges Cuvier, and partly because many scientists doubted that the dodo had ever existed. It seemed altogether too strange a creature, and many believed it a myth. The bird was first used as an example of human-induced extinction in Penny Magazine in 1833, and has since been referred to as an "icon" of extinction. Physical remains 17th-century specimens The only extant remains of dodos taken to Europe in the 17th century are a dried head and foot in the Oxford University Museum of Natural History, a foot once housed in the British Museum but now lost, a skull in the University of Copenhagen Zoological Museum, and an upper jaw in the National Museum, Prague. The last two were rediscovered and identified as dodo remains in the mid-19th century. Several stuffed dodos were also mentioned in old museum inventories, but none are known to have survived. Apart from these remains, a dried foot, which belonged to the Dutch professor Pieter Pauw, was mentioned by Carolus Clusius in 1605. Its provenance is unknown, and it is now lost, but it may have been collected during the Van Neck voyage. Supposed stuffed dodos seen in museums around the world today have in fact been made from feathers of
be due to introduction of domestic pigs and crab-eating macaques, and competition from introduced plants. Catling (2001) in a summary cites Owadally and Temple (1979), and Witmer (1991). Hershey (2004) reviewed the flaws in Temple's dodo-tambalacoque hypothesis. In 2004, Botanical Society of America's Plant Science Bulletin disputed Dr. Temple's research as flawed. The Bulletin published evidence as to why the dodo's extinction did not directly cause the increasing disappearance of young trees, including suggestions that tortoises would have been more likely to disperse the seeds than dodos, casting doubt on Temple's view as to the dodo and the tree's sole survival relationship. Uses This dodo tree is highly valued for its wood in Mauritius, which has led some foresters to scrape the pits by hand to make them sprout and grow. See also Sideroxylon majus, a species native to Réunion, that has been confounded with Sideroxylon grandiflorum (particularly under its synonym Calvaria major) References External links Catling, P. M. (2001): Extinction and the importance of history and dependence in conservation. Biodiversity 2(3): 2-13 pdf Helfferich, C. (1990): The Turkey and the Tambalacoque Tree Hershey, D. R. (2004): The widespread misconception that the tambalacoque absolutely required the dodo for its seeds to germinate. Plant Science Bulletin 50: 105–108. Hill, A. W. (1941): The genus Calvaria, with an account of the stony endocarp and germination of the seed, and description of the new species. Annals of Botany 5(4): 587–606. PDF fulltext (requires user account) King, H. C. (1946): Interim Report on Indigenous Species	dodo tree, is a long-lived tree in the family Sapotaceae, endemic to Mauritius. It is valued for its timber. The Sideroxylon grandiflorum fruit is analogous to the peach. They are both termed drupes because both have a hard endocarp, or pit, surrounding the seed, with the endocarp naturally splitting along a fracture line during germination. History In 1973, it was thought that this species was dying out. There were supposedly only 13 specimens left, all estimated to be about 300 years old. The true age could not be determined because tambalacoque has no growth rings. Stanley Temple hypothesized that the dodo, which became extinct in the 17th century, ate tambalacoque fruits, and only by passing through the digestive tract of the dodo could the seeds germinate. Temple (1977) force-fed seventeen tambalacoque fruits to wild turkeys. Seven of the fruits were crushed by the bird's gizzard. The remaining ten were either regurgitated or passed with the bird's feces. Temple planted the remaining ten fruits and three germinated. Temple did not try to germinate any seeds from control fruits not fed to turkeys so the effect of feeding fruits to turkeys was unclear. Reports made on tambalacoque seed germination by Hill (1941) and King (1946) found the seeds germinated without abrading. Temple's hypothesis that the tree required the dodo has been contested. Others have suggested the decline of the tree was exaggerated, or that other extinct animals may also have been distributing the seeds, such as tortoises, fruit bats or the broad-billed parrot. Wendy Strahm and Anthony Cheke, two experts in Mascarene ecology, claim that while a rare tree, it has germinated since the demise of the dodo and numbers a few hundred, not 13. The difference in numbers is because young trees are not distinct in appearance and may easily be confused with similar species. The decline of the tree may possibly be due to introduction of domestic
Generation, Star Trek: Voyager, and the film Star Trek: First Contact. He is also known in animation as the mad scientist Dr. Animo in the Ben 10 series, Adrian Toomes/Vulture in some Marvel video games, Chef Mung Daal in the children's animated series Chowder, and Eddie the Squirrel in CatDog. Early life Schultz is of German descent and a Roman Catholic. He attended Calvert Hall College High School and Towson University. Career Schultz's breakthrough role was the character of Captain "Howling Mad" Murdock on The A-Team. He appeared in several films, including The Fan (1981), and he starred in Fat Man and Little Boy (1989) as J. Robert Oppenheimer. In the early 1990s, he had a recurring role as Lieutenant Reginald Barclay in Star Trek: The Next Generation, and he reprised the role in Star	has been sexually abused. In November 2009, Schultz confirmed that he and former A-Team co-star Dirk Benedict would make cameo appearances in the feature film The A-Team. Schultz hosted a conservative talk radio podcast called Howling Mad Radio which ended in March 2009. He has also guest-hosted on numerous occasions for Michael Savage on The Savage Nation, Jerry Doyle on The Jerry Doyle Show, and Rusty Humphries on The Rusty Humphries Show. Personal life Schultz married actress Wendy Fulton in 1983. Their daughter Ava (born 1987) serves in the Marines. Schultz is a Roman Catholic and a conservative, and he began regular appearances on The Glazov Gang in 2012, an Internet political talk show hosted by Jamie Glazov, managing editor of FrontPage Magazine. He also posts political commentaries and podcasts on his official fansite. Filmography Film Television Video games Broadway Night and Day The Crucifer of Blood The Water Engine Radio Dark Matters
the density of a material. Increasing the temperature generally decreases the density, but there are notable exceptions to this generalization. For example, the density of water increases between its melting point at 0 °C and 4 °C; similar behavior is observed in silicon at low temperatures. The effect of pressure and temperature on the densities of liquids and solids is small. The compressibility for a typical liquid or solid is 10−6 bar−1 (1 bar = 0.1 MPa) and a typical thermal expansivity is 10−5 K−1. This roughly translates into needing around ten thousand times atmospheric pressure to reduce the volume of a substance by one percent. (Although the pressures needed may be around a thousand times smaller for sandy soil and some clays.) A one percent expansion of volume typically requires a temperature increase on the order of thousands of degrees Celsius. In contrast, the density of gases is strongly affected by pressure. The density of an ideal gas is where is the molar mass, is the pressure, is the universal gas constant, and is the absolute temperature. This means that the density of an ideal gas can be doubled by doubling the pressure, or by halving the absolute temperature. In the case of volumic thermal expansion at constant pressure and small intervals of temperature the temperature dependence of density is where is the density at a reference temperature, is the thermal expansion coefficient of the material at temperatures close to . Density of solutions The density of a solution is the sum of mass (massic) concentrations of the components of that solution. Mass (massic) concentration of each given component ρi in a solution sums to density of the solution, Expressed as a function of the densities of pure components of the mixture and their volume participation, it allows the determination of excess molar volumes: provided that there is no interaction between the components. Knowing the relation between excess volumes and activity coefficients of the components, one can determine the activity coefficients: Densities Various materials Selected chemical elements are listed here. For the densities of all chemical elements, see List of chemical elements Others Water Air Molar volumes of liquid and solid phase of elements Common units The SI unit for density is: kilogram per cubic metre (kg/m3) The litre and tonne are not part of the SI, but are acceptable for use with it, leading to the following units: kilogram per litre (kg/L) gram per millilitre (g/mL) tonne per cubic metre (t/m3) Densities using the following metric units all have exactly the same numerical value, one thousandth of the value in (kg/m3). Liquid water has a density of about 1 kg/dm3, making any of these SI units numerically convenient to use as most solids and liquids have densities between 0.1 and 20 kg/dm3. kilogram per cubic decimetre (kg/dm3) gram per cubic centimetre (g/cm3) 1 g/cm3 = 1000 kg/m3 megagram (metric ton) per cubic metre (Mg/m3) In US customary units density can be stated in: Avoirdupois ounce per cubic inch (1 g/cm3 ≈ 0.578036672 oz/cu in) Avoirdupois ounce per fluid ounce (1 g/cm3 ≈ 1.04317556 oz/US fl oz = 1.04317556 lb/US fl pint) Avoirdupois pound per cubic inch (1 g/cm3 ≈ 0.036127292 lb/cu in) pound per cubic foot (1 g/cm3 ≈ 62.427961 lb/cu ft) pound per cubic yard (1 g/cm3 ≈ 1685.5549 lb/cu yd) pound per US liquid gallon (1 g/cm3 ≈ 8.34540445 lb/US gal) pound per US bushel (1 g/cm3 ≈ 77.6888513 lb/bu) slug per cubic foot Imperial units differing from the above (as the Imperial gallon and bushel differ from the US units) in practice are rarely used, though found in older documents. The Imperial gallon was based on the concept that an Imperial fluid ounce of water would have a mass of one Avoirdupois ounce, and indeed 1 g/cm3 ≈ 1.00224129 ounces per Imperial fluid ounce = 10.0224129 pounds per Imperial gallon. The density of precious metals could conceivably be based on Troy ounces and pounds, a possible cause of confusion. Knowing the volume of the unit cell of a crystalline material and its formula weight (in daltons), the density can be calculated. One dalton per cubic ångström is equal to a density of 1.660 539 066 60 g/cm3. See also Densities of the elements (data page) List of elements by density Air density Area density Bulk density Buoyancy Charge density Density prediction by the Girolami method Dord Energy density Lighter than air Linear density Number density Orthobaric density Paper density Specific weight Spice (oceanography) Standard temperature and pressure References External links Video: Density Experiment with Oil and Alcohol Video: Density Experiment with Whiskey and Water Glass Density Calculation – Calculation of the density of glass at room temperature and of glass melts at 1000 – 1400°C List of Elements of the Periodic Table – Sorted by Density Calculation of saturated liquid densities for some components Field density test Water – Density and specific weight Temperature dependence of the density of water – Conversions of density units A delicious density experiment Water density calculator Water density for a given salinity and temperature. Liquid density calculator Select	the densities of liquids and solids is small. The compressibility for a typical liquid or solid is 10−6 bar−1 (1 bar = 0.1 MPa) and a typical thermal expansivity is 10−5 K−1. This roughly translates into needing around ten thousand times atmospheric pressure to reduce the volume of a substance by one percent. (Although the pressures needed may be around a thousand times smaller for sandy soil and some clays.) A one percent expansion of volume typically requires a temperature increase on the order of thousands of degrees Celsius. In contrast, the density of gases is strongly affected by pressure. The density of an ideal gas is where is the molar mass, is the pressure, is the universal gas constant, and is the absolute temperature. This means that the density of an ideal gas can be doubled by doubling the pressure, or by halving the absolute temperature. In the case of volumic thermal expansion at constant pressure and small intervals of temperature the temperature dependence of density is where is the density at a reference temperature, is the thermal expansion coefficient of the material at temperatures close to . Density of solutions The density of a solution is the sum of mass (massic) concentrations of the components of that solution. Mass (massic) concentration of each given component ρi in a solution sums to density of the solution, Expressed as a function of the densities of pure components of the mixture and their volume participation, it allows the determination of excess molar volumes: provided that there is no interaction between the components. Knowing the relation between excess volumes and activity coefficients of the components, one can determine the activity coefficients: Densities Various materials Selected chemical elements are listed here. For the densities of all chemical elements, see List of chemical elements Others Water Air Molar volumes of liquid and solid phase of elements Common units The SI unit for density is: kilogram per cubic metre (kg/m3) The litre and tonne are not part of the SI, but are acceptable for use with it, leading to the following units: kilogram per litre (kg/L) gram per millilitre (g/mL) tonne per cubic metre (t/m3) Densities using the following metric units all have exactly the same numerical value, one thousandth of the value in (kg/m3). Liquid water has a density of about 1 kg/dm3, making any of these SI units numerically convenient to use as most solids and liquids have densities between 0.1 and 20 kg/dm3. kilogram per cubic decimetre (kg/dm3) gram per cubic centimetre (g/cm3) 1 g/cm3 = 1000 kg/m3 megagram (metric ton) per cubic metre (Mg/m3) In US customary units density can be stated in: Avoirdupois ounce per cubic inch (1 g/cm3 ≈ 0.578036672 oz/cu in) Avoirdupois ounce per fluid ounce (1 g/cm3 ≈ 1.04317556 oz/US fl oz = 1.04317556 lb/US fl pint) Avoirdupois pound per cubic inch (1 g/cm3 ≈ 0.036127292 lb/cu in) pound per cubic foot (1 g/cm3 ≈ 62.427961 lb/cu ft) pound per cubic yard (1 g/cm3 ≈ 1685.5549 lb/cu yd) pound per US liquid gallon (1 g/cm3 ≈ 8.34540445 lb/US gal) pound per US bushel (1 g/cm3 ≈ 77.6888513 lb/bu) slug per cubic foot Imperial units differing from the above (as the Imperial gallon and bushel differ from the US units) in practice are rarely used, though found in older documents. The Imperial gallon was based on the concept that an Imperial fluid ounce of water would have a mass of one Avoirdupois ounce, and indeed 1 g/cm3 ≈ 1.00224129 ounces per Imperial fluid ounce = 10.0224129 pounds per Imperial gallon. The density of precious metals could conceivably be based on Troy ounces and pounds, a possible cause of confusion. Knowing the volume of the unit cell of a crystalline material and its formula weight (in daltons), the density can be calculated. One dalton per cubic ångström is equal to a density of 1.660 539 066 60 g/cm3. See also Densities of the elements (data page) List of elements by density Air density Area density Bulk density Buoyancy Charge density Density prediction by the Girolami method Dord Energy density Lighter than air Linear density Number density Orthobaric density Paper density Specific weight Spice (oceanography) Standard temperature and pressure References External links Video: Density Experiment with Oil and Alcohol Video: Density Experiment with Whiskey and Water Glass Density Calculation – Calculation of the density of glass at room temperature and of glass melts at 1000 – 1400°C List of Elements of the Periodic Table – Sorted by Density Calculation of saturated liquid densities for some components Field density test Water
Barry on lead guitar and vocals. They performed an original song called "The Tupperware Song" at the Tupperware headquarters in Orlando, Florida. Beginning in 1992, Barry played lead guitar in the Rock Bottom Remainders, a rock band made up of published authors. (Remainder is a publishing term for a book that doesn't sell.) The band was founded by Barry's sister-in-law, Kathi Kamen Goldmark, for an American Booksellers Association convention, and has also included Stephen King, Amy Tan, Ridley Pearson, Scott Turow, Mitch Albom, Roy Blount Jr., Barbara Kingsolver, Matt Groening, and Barry's brother Sam, among others. The band's members "are not musically skilled, but they are extremely loud," according to Barry. Several high-profile musicians, including Al Kooper, Warren Zevon, and Roger McGuinn, have performed with the band, and Bruce Springsteen sat in at least once. The band's road tour resulted in the book Mid-Life Confidential: The Rock Bottom Remainders Tour America with Three Chords and an Attitude. The Rock Bottom Remainders disbanded in 2012 following Goldmark's death from breast cancer. They have reunited several times, performing at the Tucson Festival of books in 2016 and 2018. Other activities Beginning in 1984, Barry and Tropic editors Gene Weingarten and Tom Shroder have organized the Tropic Hunt (now the Herald Hunt), an annual puzzlehunt in Miami. A Washington, D.C., spinoff, the Post Hunt, began in 2008. Barry has run several mock campaigns for President of the United States, running on a libertarian platform. He has also written for the Libertarian Party's national newsletter. The screen adaptation of Barry's book Dave Barry's Complete Guide to Guys was released in 2005; it is available on DVD. Personal life Barry married Lois Ann Shelnutt in 1969. He next married Beth Lenox, in 1976. Barry and Lenox worked together at the Daily Local News, where they began their journalism careers on the same day in September 1971; they had one child, Robert, born October 8, 1980. Barry and Lenox divorced in 1993. Barry experienced tragedy in his family; his father David W and his youngest brother suffered alcoholism, and his father died in 1984, his sister Mary Katherine was institutionalized for schizophrenia, and his mother died by suicide in 1987. In 1996, Barry married Miami Herald sportswriter Michelle Kaufman; they had a daughter, Sophie, in 2000. Barry has had dogs named Goldie, Earnest, Zippy, and now Lucy. All have been mentioned regularly in Barry's columns. Works Non-fiction The Taming of the Screw (1983, with illustrator Jerry O'Brien) Babies and Other Hazards of Sex: How to Make a Tiny Person in Only 9 Months With Tools You Probably Have Around the Home (1984, with illustrator Jerry O'Brien) Stay Fit and Healthy Until You're Dead (1985, with illustrator Jerry O'Brien) Claw Your Way to the Top: How to Become the Head of a Major Corporation in Roughly a Week (1986, with illustrator Jerry O'Brien) Dave Barry's Guide to Marriage and/or Sex (1987 with illustrator Jerry O'Brien) Homes and Other Black Holes (1988) Dave Barry Slept Here: A Sort of History of the United States (1989) Dave Barry Turns 40 (1990) Dave Barry's Only Travel Guide You'll Ever Need (1991) Dave Barry's Guide to Life (1991) (includes Dave Barry's Guide to Marriage and/or Sex, Babies and Other Hazards of Sex, Stay Fit and Healthy Until You're Dead and Claw Your Way to the Top) Dave Barry Does Japan (1992) Dave Barry's Gift Guide to End All Gift Guides (1994) Dave Barry's Complete Guide to Guys (1996) Dave Barry in Cyberspace (1996) Dave Barry's Book of Bad Songs (1997) Dave Barry Turns 50 (1998) Dave Barry Hits Below the Beltway: A Vicious and Unprovoked Attack on Our Most Cherished Political Institutions (2001) "My Teenage Son's Goal in Life is to Make Me Feel 3,500 Years Old" and Other Thoughts On Parenting From Dave Barry (2001) "The Greatest Invention in the History Of Mankind Is Beer" And Other Manly Insights From Dave Barry (2001) Dave Barry's Money Secrets (2006) Dave Barry on Dads (2007) Dave Barry's History of the Millennium (So Far) (2007) I'll Mature When I'm Dead: Dave Barry's Amazing Tales of Adulthood (2010) You Can Date Boys When You're Forty: Dave Barry on Parenting and Other Topics He Knows Very Little About (2014) Live Right and Find Happiness (Although Beer is Much Faster): Life Lessons and Other Ravings from Dave Barry (2015) Best. State. Ever.: A Florida Man Defends His Homeland (2015) For This We Left Egypt?: A Passover Haggadah for Jews and Those Who Love Them (2017, with Alan Zweibel and Adam Mansbach) Lessons from Lucy (2019) A Field Guide to the Jewish People (2019, with Adam Mansbach and Alan Zweibel) Collected columns Dave Barry's Bad Habits: A 100% Fact-Free Book (1985) Dave Barry's Greatest Hits (1988) Dave Barry Talks Back (1991) The World According to Dave Barry (1994) (includes Dave Barry Talks Back, Dave Barry Turns 40 and Dave Barry's Greatest Hits) Dave Barry is NOT Making This Up (1995) Dave Barry Is from Mars and Venus (1997) Dave Barry Is Not Taking This Sitting Down (2000) Boogers Are My Beat (2003) Fiction Big Trouble (1999) Tricky Business (2002) Peter and the Starcatchers (2004, with Ridley Pearson) Peter and the Shadow Thieves (2006, with Ridley Pearson) Peter and the Secret of Rundoon (2007, with Ridley Pearson) Escape From the Carnivale (2006, with Ridley Pearson) The Shepherd, the Angel, and Walter the Christmas Miracle Dog (2006) Cave of the Dark Wind (2007, with Ridley Pearson) Science Fair (2008, with Ridley Pearson) Peter and the	show starred Harry Anderson as Barry and DeLane Matthews as his wife Beth. In an early episode, Barry appeared in a cameo role. After four seasons, the program was canceled shortly after being moved from its "coveted" Monday night slot to the "Friday night death slot," so named because of its association with low viewership. Music During college, Barry was in a band called the Federal Duck. While at the Miami Herald, he and several of his colleagues created a band called the Urban Professionals, with Barry on lead guitar and vocals. They performed an original song called "The Tupperware Song" at the Tupperware headquarters in Orlando, Florida. Beginning in 1992, Barry played lead guitar in the Rock Bottom Remainders, a rock band made up of published authors. (Remainder is a publishing term for a book that doesn't sell.) The band was founded by Barry's sister-in-law, Kathi Kamen Goldmark, for an American Booksellers Association convention, and has also included Stephen King, Amy Tan, Ridley Pearson, Scott Turow, Mitch Albom, Roy Blount Jr., Barbara Kingsolver, Matt Groening, and Barry's brother Sam, among others. The band's members "are not musically skilled, but they are extremely loud," according to Barry. Several high-profile musicians, including Al Kooper, Warren Zevon, and Roger McGuinn, have performed with the band, and Bruce Springsteen sat in at least once. The band's road tour resulted in the book Mid-Life Confidential: The Rock Bottom Remainders Tour America with Three Chords and an Attitude. The Rock Bottom Remainders disbanded in 2012 following Goldmark's death from breast cancer. They have reunited several times, performing at the Tucson Festival of books in 2016 and 2018. Other activities Beginning in 1984, Barry and Tropic editors Gene Weingarten and Tom Shroder have organized the Tropic Hunt (now the Herald Hunt), an annual puzzlehunt in Miami. A Washington, D.C., spinoff, the Post Hunt, began in 2008. Barry has run several mock campaigns for President of the United States, running on a libertarian platform. He has also written for the Libertarian Party's national newsletter. The screen adaptation of Barry's book Dave Barry's Complete Guide to Guys was released in 2005; it is available on DVD. Personal life Barry married Lois Ann Shelnutt in 1969. He next married Beth Lenox, in 1976. Barry and Lenox worked together at the Daily Local News, where they began their journalism careers on the same day in September 1971; they had one child, Robert, born October 8, 1980. Barry and Lenox divorced in 1993. Barry experienced tragedy in his family; his father David W and his youngest brother suffered alcoholism, and his father died in 1984, his sister Mary Katherine was institutionalized for schizophrenia, and his mother died by suicide in 1987. In 1996, Barry married Miami Herald sportswriter Michelle Kaufman; they had a daughter, Sophie, in 2000. Barry has had dogs named Goldie, Earnest, Zippy, and now Lucy. All have been mentioned regularly in Barry's columns. Works Non-fiction The Taming of the Screw (1983, with illustrator Jerry O'Brien) Babies and Other Hazards of Sex: How to Make a Tiny Person in Only 9 Months With Tools You Probably Have Around the Home (1984, with illustrator Jerry O'Brien) Stay Fit and Healthy Until You're Dead (1985, with illustrator Jerry O'Brien) Claw Your Way to the Top: How to Become the Head of a Major Corporation in Roughly a Week (1986, with illustrator Jerry O'Brien) Dave Barry's Guide to Marriage and/or Sex (1987 with illustrator Jerry O'Brien) Homes and Other Black Holes (1988) Dave Barry Slept Here: A Sort of History of the United States (1989) Dave Barry Turns 40 (1990) Dave Barry's Only Travel Guide You'll Ever Need (1991) Dave Barry's Guide to Life (1991) (includes Dave Barry's Guide to Marriage and/or Sex, Babies and Other Hazards of Sex, Stay Fit and Healthy Until You're Dead and Claw Your Way to the Top) Dave Barry Does Japan (1992) Dave Barry's Gift Guide to End All Gift Guides (1994) Dave Barry's Complete Guide to Guys (1996) Dave Barry in Cyberspace (1996) Dave Barry's Book of Bad Songs (1997) Dave Barry Turns 50 (1998) Dave Barry Hits Below the Beltway: A Vicious and Unprovoked Attack on Our Most Cherished Political Institutions (2001) "My Teenage Son's Goal in Life is to Make Me Feel 3,500 Years Old" and Other Thoughts On Parenting From Dave Barry (2001) "The Greatest Invention in the History Of Mankind Is Beer" And Other Manly Insights From Dave Barry (2001) Dave Barry's Money Secrets (2006) Dave Barry on Dads (2007) Dave Barry's History of the Millennium (So Far) (2007) I'll Mature When I'm Dead: Dave Barry's Amazing Tales of Adulthood (2010) You Can Date Boys When You're Forty: Dave Barry on Parenting and Other Topics He Knows Very Little
the comedy series Wings. Death Angell and his wife, Lynn, were among the passengers of American Airlines Flight 11 killed in the September 11 attacks on the World Trade Center in Manhattan, New York City in 2001. By coincidence, in an episode Angell cowrote for Frasier, a stranger leaves a telephone message for the title character saying that she will soon arrive on "American Flight 11". Legacy The American Screenwriters Association awards the annual David Angell Humanitarian Award to any individual in the entertainment industry who contributes to global well-being through donations of time, expertise or other support to improve the human condition. In 2004, The Angell Foundation of Los Angeles, California, awarded Providence College a gift of $2 million for the Smith Center for the Arts. The two-part episode of Frasier to air after the attacks, "Don Juan in Hell" airing on September 25, 2001, ended with the memorial tribute, "In loving memory of our friends Lynn and David Angell". "Goodnight, Seattle", series finale that	in 1989, which Angell, Casey, Lee and the series' other producers shared, and an Outstanding Writing/Comedy Emmy for Cheers, which Angell received in 1984. After working together as producers on Cheers, Angell, Casey and Lee formed Grub Street Productions. In 1990, they created and executive-produced the comedy series Wings. Death Angell and his wife, Lynn, were among the passengers of American Airlines Flight 11 killed in the September 11 attacks on the World Trade Center in Manhattan, New York City in 2001. By coincidence, in an episode Angell cowrote for Frasier, a stranger leaves a telephone message for the title character saying that she will soon arrive on "American Flight 11". Legacy The American Screenwriters Association awards the annual David Angell Humanitarian Award to any individual in the entertainment industry who contributes to global well-being through donations of time, expertise or other support to improve the human condition. In 2004, The Angell Foundation of Los Angeles, California, awarded Providence College a gift of $2 million for the Smith Center for the Arts. The two-part episode of Frasier to air after the attacks, "Don
a German missionary, Africanist, and linguist. He substantially extended and revised the work of Carl Meinhof, his teacher, although he rejected some of Meinhof's theories only implicitly. Westermann is seen as one of the founders of modern African linguistics. He carried out extensive linguistic and anthropological research in the area ranging from Senegal eastwards to the Upper Nile. His linguistic publications cover a wide range of African languages, including the Gbe languages, Nuer, Kpelle, Shilluk, Hausa, and Guang. Westermann's comparative work, begun in 1911, initially brought together much of today's Niger–Congo and Nilo-Saharan language phyla under the name Sudanic languages. His most important later publication Die westlichen Sudansprachen 1927a divided these into East and West Sudanic languages and laid the basis for what would become Niger–Congo. In this book and a series of associated articles between 1925 and 1928, Westermann both identified a large number of roots that form the basis of our understanding of Niger–Congo and set out the evidence for the coherence of many of the families that constitute it. Much of the classification of African languages associated with Joseph Greenberg actually derives from the work of Westermann. In 1927 Westermann published a Practical Orthography of African Languages, which became later known as the Westermann script. Subsequently, he published the influential and oft-reprinted Practical Phonetics for Students of African Languages in collaboration with Ida C. Ward (1933). He was born in Baden near	linguistic publications cover a wide range of African languages, including the Gbe languages, Nuer, Kpelle, Shilluk, Hausa, and Guang. Westermann's comparative work, begun in 1911, initially brought together much of today's Niger–Congo and Nilo-Saharan language phyla under the name Sudanic languages. His most important later publication Die westlichen Sudansprachen 1927a divided these into East and West Sudanic languages and laid the basis for what would become Niger–Congo. In this book and a series of associated articles between 1925 and 1928, Westermann both identified a large number of roots that form the basis of our understanding of Niger–Congo and set out the evidence for the coherence of many of the families that constitute it. Much of the classification of African languages associated with Joseph Greenberg actually derives from the work of Westermann. In 1927 Westermann published
kahakō (macron) over vowels, although there is some disagreement over considering them as individual letters. The kahakō over a vowel can completely change the meaning of a word that is spelled the same but without the kahakō. Kurdish uses the symbols Ç, Ê, Î, Ş and Û with other 26 standard Latin alphabet symbols. Lakota alphabet uses the caron for the letters č, ȟ, ǧ, š, and ž. It also uses the acute accent for stressed vowels á, é, í, ó, ú, áŋ, íŋ, úŋ. Malay uses some diacritics such as á, ā, ç, í, ñ, ó, š, ú. Uses of diacritics was continued until late 19th century except ā and ē. Maltese uses a C, G, and Z with a dot over them (Ċ, Ġ, Ż), and also has an H with an extra horizontal bar. For uppercase H, the extra bar is written slightly above the usual bar. For lowercase H, the extra bar is written crossing the vertical, like a t, and not touching the lower part (Ħ, ħ). The above characters are considered separate letters. The letter 'c' without a dot has fallen out of use due to redundancy. 'Ċ' is pronounced like the English 'ch' and 'k' is used as a hard c as in 'cat'. 'Ż' is pronounced just like the English 'Z' as in 'Zebra', while 'Z' is used to make the sound of 'ts' in English (like 'tsunami' or 'maths'). 'Ġ' is used as a soft 'G' like in 'geometry', while the 'G' sounds like a hard 'G' like in 'log'. The digraph 'għ' (called għajn after the Arabic letter name ʻayn for غ) is considered separate, and sometimes ordered after 'g', whilst in other volumes it is placed between 'n' and 'o' (the Latin letter 'o' originally evolved from the shape of Phoenician ʻayin, which was traditionally collated after Phoenician nūn). The romanization of Syriac uses the altered letters of. Ā, Č, Ḏ, Ē, Ë, Ġ, Ḥ, Ō, Š, Ṣ, Ṭ, Ū, Ž alongside the 26 standard Latin alphabet symbols. Vietnamese uses the horn diacritic for the letters ơ and ư; the circumflex for the letters â, ê, and ô; the breve for the letter ă; and a bar through the letter đ. Separately, it also has á, à, ả, ã and ạ, the five tones used for vowels besides the flat tone 'a'. Cyrillic letters Belarusian and Uzbek Cyrillic have a letter ў. Belarusian, Bulgarian, Russian and Ukrainian have the letter й. Belarusian and Russian have the letter ё. In Russian, this letter is usually replaced by е, although it has a different pronunciation. The use of е instead of ё does not affect the pronunciation. Ё is always used in children's books and in dictionaries. A minimal pair is все (vs'e, "everybody" pl.) and всё (vs'o, "everything" n. sg.). In Belarusian the replacement by е is a mistake; in Russian, it is permissible to use either е or ё for ё but the former is more common in everyday writing (as opposed to instructional or juvenile writing). The Cyrillic Ukrainian alphabet has the letters ґ, й and ї. Ukrainian Latynka has many more. Macedonian has the letters ќ and ѓ. In Bulgarian and Macedonian the possessive pronoun ѝ (ì, "her") is spelled with a grave accent in order to distinguish it from the conjunction и (i, "and"). The acute accent " ́" above any vowel in Cyrillic alphabets is used in dictionaries, books for children and foreign learners to indicate the word stress, it also can be used for disambiguation of similarly spelled words with different lexical stresses. Diacritics that do not produce new letters English English is one of the few European languages that does not have many words that contain diacritical marks. Instead, digraphs are the main way the Modern English alphabet adapts the Latin to its phonemes. Exceptions are unassimilated foreign loanwords, including borrowings from French and, increasingly, Spanish like jalapeño; however, the diacritic is also sometimes omitted from such words. Loanwords that frequently appear with the diacritic in English include café, résumé or resumé (a usage that helps distinguish it from the verb resume), soufflé, and naïveté (see English terms with diacritical marks). In older practice (and even among some orthographically conservative modern writers) one may see examples such as élite, mêlée and rôle. English speakers and writers once used the diaeresis more often than now in words such as coöperation (from Fr. coopération), zoölogy (from Grk. zoologia), and seeër (now more commonly see-er or simply seer) as a way of indicating that adjacent vowels belonged to separate syllables, but this practice has become far less common. The New Yorker magazine is a major publication that continues to use the diaeresis in place of a hyphen for clarity and economy of space. A few English words, out of context, can only be distinguished from others by a diacritic or modified letter, including exposé, lamé, maté, öre, øre, pâté, and rosé. The same is true of résumé, alternatively but nevertheless it is regularly spelled resume. In a few words, diacritics that did not exist in the original have been added for disambiguation, as in maté (from Sp. and Port. mate), saké (the standard Romanization of the Japanese has no accent mark), and Malé (from Dhivehi މާލެ), to clearly distinguish them from the English words "mate", "sake", and "male". The acute and grave accents are occasionally used in poetry and lyrics: the acute to indicate stress overtly where it might be ambiguous (rébel vs. rebél) or nonstandard for metrical reasons (caléndar), the grave to indicate that an ordinarily silent or elided syllable is pronounced (warnèd, parlìament). In certain personal names such as Renée and Zoë, often two spellings exist, and the preference will be known only to those close to the person themselves. Even when the name of a person is spelled with a diacritic, like Charlotte Brontë, this may be dropped in English language articles and even official documents such as passports either due to carelessness, the typist not knowing how to enter letters with diacritical marks, or for technical reasons—California, for example, does not allow names with diacritics, as the computer system cannot process such characters. They also appear in some worldwide company names and/or trademarks such as Nestlé or Citroën. Other languages The following languages have letter-diacritic combinations that are not considered independent letters. Afrikaans uses a diaeresis to mark vowels that are pronounced separately and not as one would expect where they occur together, for example voel (to feel) as opposed to voël (bird). The circumflex is used in ê, î, ô and û generally to indicate long close-mid, as opposed to open-mid vowels, for example in the words wêreld (world) and môre (morning, tomorrow). The acute accent is used to add emphasis in the same way as underlining or writing in bold or italics in English, for example Dit is jóú boek (It is your book). The grave accent is used to distinguish between words that are different only in placement of the stress, for example appel (apple) and appèl (appeal) and in a few cases where it makes no difference to the pronunciation but distinguishes between homophones. The two most usual cases of the latter are in the sayings òf... òf (either... or) and nòg... nòg (neither... nor) to distinguish them from of (or) and nog (again, still). Aymara uses a diacritical horn over p, q, t, k, ch. Catalan has the following composite characters: à, ç, é, è, í, ï, ó, ò, ú, ü, l·l. The acute and the grave indicate stress and vowel height, the cedilla marks the result of a historical palatalization, the diaeresis indicates either a hiatus, or that the letter u is pronounced when the graphemes gü, qü are followed by e or i, the interpunct (·) distinguishes the different values of ll/l·l. Some orthographies of Cornish such as Kernowek Standard and Unified Cornish use diacritics, while others such as Kernewek Kemmyn and the Standard Written Form do not (or only use them optionally in teaching materials). Dutch uses the diaeresis. For example, in ruïne it means that the u and the i are separately pronounced in their usual way, and not in the way that the combination ui is normally pronounced. Thus it works as a separation sign and not as an indication for an alternative version of the i. Diacritics can be used for emphasis (érg koud for very cold) or for disambiguation between a number of words that are spelled the same when context doesn't indicate the correct meaning (één appel = one apple, een appel = an apple; vóórkomen = to occur, voorkómen = to prevent). Grave and acute accents are used on a very small number of words, mostly loanwords. The ç also appears in some loanwords. Faroese. Non-Faroese accented letters are not added to the Faroese alphabet. These include é, ö, ü, å and recently also letters like š, ł, and ć. Filipino has the following composite characters: á, à, â, é, è, ê, í, ì, î, ó, ò, ô, ú, ù, û. The actual use of diacritics for Filipino is, however, uncommon, meant only to distinguish between homonyms with different stresses and meanings that either occur near each other in a text or to aid the reader in ascertaining its otherwise ambiguous meaning. The letter eñe is due to the Spanish alphabet and too, is considered a separate letter. The diacritics appears in Spanish loanwords and names if Spanish orthography is observed. Finnish. Carons in š and ž appear only in foreign proper names and loanwords, but may be substituted with sh or zh if and only if it is technically impossible to produce accented letters in the medium. Contrary to Estonian, š and ž are not considered distinct letters in Finnish. French uses five diacritics. The grave (accent grave) marks the sound when over an e, as in père ("father") or is used to distinguish words that are otherwise homographs such as a/à ("has"/"to") or ou/où ("or"/"where"). The acute (accent aigu) is only used in "é", modifying the "e" to make the sound , as in étoile ("star"). The circumflex (accent circonflexe) generally denotes that an S once followed the vowel in Old French or Latin, as in fête ("party"), the Old French being feste and the Latin being festum. Whether the circumflex modifies the vowel's pronunciation depends on the dialect and the vowel. The cedilla (cédille) indicates that a normally hard "c" (before the vowels "a", "o", and "u") is to be pronounced , as in ça ("that"). The diaeresis (tréma) indicates that two adjacent vowels that would normally be pronounced as one are to be pronounced separately, as in Noël ("Christmas"). Galician vowels can bear an acute (á, é, í, ó, ú) to indicate stress or difference between two otherwise same written words (é, 'is' vs. e, 'and'), but the diaeresis (trema) is only used with ï and ü to show two separate vowel sounds in pronunciation. Only in foreign words may Galician use other diacritics such as ç (common during the Middle Ages), ê, or à. German uses the three umlauted characters ä, ö and ü. These diacritics indicate vowel changes. For instance, the word Ofen "oven" has the plural Öfen . The mark originated as a superscript e; a handwritten blackletter e resembles two parallel vertical lines, like a diaeresis. Due to this history, "ä", "ö" and "ü" can be written as "ae", "oe" and "ue" respectively, if the umlaut letters are not available. Hebrew has many various diacritic marks known as niqqud that are used above and	rare words, e.g. is not written out with the original alif found in the word pronunciation, instead it is written out as . (In Arabic: also called ): (ــَـ) (a) (ــِـ) (i) (ــُـ) (u) (ــْـ) (no vowel) The or vowel points serve two purposes: They serve as a phonetic guide. They indicate the presence of short vowels (, , or ) or their absence (). At the last letter of a word, the vowel point reflects the inflection case or conjugation mood. For nouns, The is for the nominative, for the accusative, and for the genitive. For verbs, the is for the imperfective, for the perfective, and the is for verbs in the imperative or jussive moods. Vowel points or should not be confused with consonant points or () – one, two or three dots written above or below a consonant to distinguish between letters of the same or similar form. Greek These diacritics are used in addition to the acute, grave, and circumflex accents and the diaeresis: – iota subscript () – rough breathing (, ): aspiration – smooth (or soft) breathing (, ): lack of aspiration Hebrew Niqqud – Dagesh – Mappiq – Rafe – Shin dot (at top right corner) – Sin dot (at top left corner) – Shva – Kubutz – Holam – Kamatz – Patakh – Segol – Tzeire – Hiriq Cantillation marks do not generally render correctly; refer to Hebrew cantillation#Names and shapes of the ta'amim for a complete table together with instructions for how to maximize the possibility of viewing them in a web browser Other – Geresh – Gershayim Korean The diacritics 〮 and 〯 , known as Bangjeom (), were used to mark pitch accents in Hangul for Middle Korean. They were written to the left of a syllable in vertical writing and above a syllable in horizontal writing. Sanskrit and Indic Syriac A dot above and a dot below a letter represent , transliterated as a or ă, Two diagonally-placed dots above a letter represent , transliterated as ā or â or å, Two horizontally-placed dots below a letter represent , transliterated as e or ĕ; often pronounced and transliterated as i in the East Syriac dialect, Two diagonally-placed dots below a letter represent , transliterated as ē, A dot underneath the Beth represent a soft sound, transliterated as v A tilde (~) placed under Gamel represent a sound, transliterated as j The letter Waw with a dot below it represents , transliterated as ū or u, The letter Waw with a dot above it represents , transliterated as ō or o, The letter Yōḏ with a dot beneath it represents , transliterated as ī or i, A tilde (~) under Kaph represent a sound, transliterated as ch or č, A semicircle under Peh represents an sound, transliterated as f or ph. In addition to the above vowel marks, transliteration of Syriac sometimes includes ə, e̊ or superscript e (or often nothing at all) to represent an original Aramaic schwa that became lost later on at some point in the development of Syriac. Some transliteration schemes find its inclusion necessary for showing spirantization or for historical reasons. Non-alphabetic scripts Some non-alphabetic scripts also employ symbols that function essentially as diacritics. Non-pure abjads (such as Hebrew and Arabic script) and abugidas use diacritics for denoting vowels. Hebrew and Arabic also indicate consonant doubling and change with diacritics; Hebrew and Devanagari use them for foreign sounds. Devanagari and related abugidas also use a diacritical mark called a virama to mark the absence of a vowel. In addition, Devanagari uses the moon-dot chandrabindu ( ँ ). Unified Canadian Aboriginal Syllabics use several types of diacritics, including the diacritics with alphabetic properties known as Medials and Finals. Although long vowels originally were indicated with a negative line through the Syllabic glyphs, making the glyph appear broken, in the modern forms, a dot above is used to indicate vowel length. In some of the styles, a ring above indicates a long vowel with a [j] off-glide. Another diacritic, the "inner ring" is placed at the glyph's head to modify [p] to [f] and [t] to [θ]. Medials such as the "w-dot" placed next to the Syllabics glyph indicates a [w] being placed between the syllable onset consonant and the nucleus vowel. Finals indicate the syllable coda consonant; some of the syllable coda consonants in word medial positions, such as with the "h-tick", indicate the fortification of the consonant in the syllable following it. The Japanese hiragana and katakana syllabaries use the dakuten (◌゛) and handakuten (◌゜) (in Japanese: 濁点 and 半濁点) symbols, also known as nigori (濁 "muddying") or ten-ten (点々 "dot dot") and maru (丸 "circle"), to indicate voiced consonants or other phonetic changes. Emoticons are commonly created with diacritic symbols, especially Japanese emoticons on popular imageboards. Alphabetization or collation Different languages use different rules to put diacritic characters in alphabetical order. French and Portuguese treat letters with diacritical marks the same as the underlying letter for purposes of ordering and dictionaries. The Scandinavian languages and the Finnish language, by contrast, treat the characters with diacritics å, ä, and ö as distinct letters of the alphabet, and sort them after z. Usually ä (a-umlaut) and ö (o-umlaut) [used in Swedish and Finnish] are sorted as equivalent to æ (ash) and ø (o-slash) [used in Danish and Norwegian]. Also, aa, when used as an alternative spelling to å, is sorted as such. Other letters modified by diacritics are treated as variants of the underlying letter, with the exception that ü is frequently sorted as y. Languages that treat accented letters as variants of the underlying letter usually alphabetize words with such symbols immediately after similar unmarked words. For instance, in German where two words differ only by an umlaut, the word without it is sorted first in German dictionaries (e.g. schon and then schön, or fallen and then fällen). However, when names are concerned (e.g. in phone books or in author catalogues in libraries), umlauts are often treated as combinations of the vowel with a suffixed e; Austrian phone books now treat characters with umlauts as separate letters (immediately following the underlying vowel). In Spanish, the grapheme ñ is considered a new letter different from n and collated between n and o, as it denotes a different sound from that of a plain n. But the accented vowels á, é, í, ó, ú are not separated from the unaccented vowels a, e, i, o, u, as the acute accent in Spanish only modifies stress within the word or denotes a distinction between homonyms, and does not modify the sound of a letter. For a comprehensive list of the collating orders in various languages, see Collating sequence. Generation with computers Modern computer technology was developed mostly in English-speaking countries, so data formats, keyboard layouts, etc. were developed with a bias favoring English, a language with an alphabet without diacritical marks. Efforts have been made to create internationalized domain names that further extend the English alphabet (e.g., "pokémon.com"). Depending on the keyboard layout, which differs amongst countries, it is more or less easy to enter letters with diacritics on computers and typewriters. Some have their own keys; some are created by first pressing the key with the diacritic mark followed by the letter to place it on. Such a key is sometimes referred to as a dead key, as it produces no output of its own but modifies the output of the key pressed after it. In modern Microsoft Windows and Linux operating systems, the keyboard layouts US International and UK International feature dead keys that allow one to type Latin letters with the acute, grave, circumflex, diaeresis, tilde, and cedilla found in Western European languages (specifically, those combinations found in the ISO Latin-1 character set) directly: + gives ë, + gives õ, etc. On Apple Macintosh computers, there are keyboard shortcuts for the most common diacritics; followed by a vowel places an acute accent, followed by a vowel gives an umlaut, gives a cedilla, etc. Diacritics can be composed in most X Window System keyboard layouts, as well as other operating systems, such as Microsoft Windows, using additional software. On computers, the availability of code pages determines whether one can use certain diacritics. Unicode solves this problem by assigning every known character its own code; if this code is known, most modern computer systems provide a method to input it. With Unicode, it is also possible to combine diacritical marks with most characters. However, as of 2019, very few fonts include the necessary support to correctly render character-plus-diacritic(s) for the Latin, Cyrillic and some other alphabets (exceptions include Andika). Languages with letters containing diacritics The following languages have letters that contain diacritics that are considered independent letters distinct from those without diacritics. Latin/Roman letters Baltic Latvian has the following letters: ā, ē, ī, ū, č, ģ, ķ, ļ, ņ, š, ž Lithuanian. In general usage, where letters appear with the caron (č, š and ž), they are considered as separate letters from c, s or z and collated separately; letters with the ogonek (ą, ę, į and ų), the macron (ū) and the superdot (ė) are considered as separate letters as well, but not given a unique collation order. Celtic Welsh uses the circumflex, diaeresis, acute, and grave on its seven vowels a, e, i, o, u, w, y (hence the composites â, ê, î, ô, û, ŵ, ŷ, ä, ë, ï, ö, ü, ẅ, ÿ, á, é, í, ó, ú, ẃ, ý, à, è, ì, ò, ù, ẁ, ỳ). Following spelling reforms since the 1970s, Scottish Gaelic uses graves only, which can be used on any vowel (à, è, ì, ò, ù). Formerly acute accents could be used on á, ó and é, which were used to indicate a specific vowel quality. With the elimination of these accents, the new orthography relies on the reader having prior knowledge of pronunciation of a given word. Manx uses the single diacritic ç combined with h to give the digraph (pronounced ) to mark the distinction between it and the digraph (pronounced or ). Other diacritics used in Manx included â, ê, ï, etc. to mark the distinction between two similarly spelled words but with slightly differing pronunciation. Irish uses only acute accents to mark long vowels, following the 1948 spelling reform. Breton does not have a single orthography (spelling system), but uses diacritics for a number of purposes. The diaeresis is used to mark that two vowels are pronounced separately and not as a diphthong/digraph. The circumflex is used to mark long vowels, but usually only when the vowel length is not predictable by phonology. Nasalization of vowels may be marked with a tilde, or following the vowel with the letter <ñ>. The plural suffix -où is used as a unified spelling to represent a suffix with a number of pronunciations in different dialects, and to distinguish this suffix from the digraph <ou> which is pronounced as . An apostrophe is used to distinguish c'h, pronounced as the digraph <ch> is used in other Celtic languages, from the French-influenced digraph ch, pronounced . Finno-Ugric Estonian has a distinct letter õ, which contains a tilde. Estonian "dotted vowels" ä, ö, ü are similar to German, but these are also distinct letters, not like German umlauted letters. All four have their own place in the alphabet, between w and x. Carons in š or ž appear only in foreign proper names and loanwords. Also these are distinct letters, placed in the alphabet between s and t. Finnish uses dotted (umlauted) vowels (ä and ö). As in Swedish and Estonian, these are regarded as individual letters, rather than vowel + umlaut combinations (as happens in German). It also uses the characters å, š and ž in foreign names and loanwords. In the Finnish and Swedish alphabets, å, ä and ö collate as separate letters after z, the others as variants of their base letter. Hungarian uses the umlaut, the acute and double acute accent (unique to Hungarian): (ö, ü), (á, é, í, ó, ú) and (ő, ű). The acute accent indicates the long form of a vowel (in case of i/í, o/ó, u/ú) while the double acute performs the same function for ö and ü. The acute accent can also indicate a different sound (more open, like in case of a/á, e/é). Both long and short forms of the vowels are listed separately in the Hungarian alphabet, but members of the pairs a/á, e/é, i/í, o/ó, ö/ő, u/ú and ü/ű are collated in dictionaries as the same letter. Livonian has the following letters: ā, ä, ǟ, ḑ, ē, ī, ļ, ņ, ō, ȯ, ȱ, õ, ȭ, ŗ, š, ț, ū, ž. Germanic Faroese uses acutes and other special letters. All are considered separate letters and have their own place in the alphabet: á, í, ó, ú, ý and ø. Icelandic uses acutes and other special letters. All are considered separate letters, and have their own place in the alphabet: á, é, í, ó, ú, ý, and ö. Danish and Norwegian use additional characters like the o-slash ø and the a-overring å. These letters come after z and æ in the order ø, å. Historically, the å has developed from a ligature by writing a small superscript a over a lowercase a; if an å character is unavailable, some Scandinavian languages allow the substitution of a doubled a. The Scandinavian languages collate these letters after z, but have different collation standards. Swedish uses a-diaeresis (ä) and o-diaeresis (ö) in the place of ash (æ) and slashed o (ø) in addition to the a-overring (å). Historically, the diaeresis for the Swedish letters ä and ö, like the German umlaut, developed from a small Gothic e written above the letters. These letters are collated after z, in the order å, ä, ö. Romance In Asturian, Galician and Spanish, the character ñ is a letter and collated between n and o. Asturian uses Ḷ (lower case ḷ), and Ḥ (lower case ḥ) Leonese: could use ñ or nn. Romanian uses a breve on the letter a (ă) to indicate the sound schwa , as well as a circumflex over the letters a (â) and i (î) for the sound . Romanian also writes a comma below the letters s (ș) and t (ț) to represent the sounds and , respectively. These characters are collated after their non-diacritic equivalent. Slavic The Bosnian, Croatian, and Serbian Latin alphabets have the symbols č, ć, đ, š and ž, which are considered separate letters and are listed as such in dictionaries and other contexts in which words are listed according to alphabetical order. They also have one digraph including a diacritic, dž, which is also alphabetized independently, and follows d and precedes đ in the alphabetical order. The Serbian Cyrillic alphabet has no diacritics, instead it has a grapheme (glyph) for every letter of its Latin counterpart (including Latin letters with diacritics and the digraphs dž, lj and nj). The Czech alphabet uses the acute (á é í ó ú ý), caron (č ď ě ň ř š ť ž), and for one letter (ů) the ring. (Note that in ď and ť the caron is modified to look rather like an apostrophe.) Polish has the following letters: ą ć ę ł ń ó ś ź ż. These are considered to be separate letters: each of them is placed in the alphabet immediately after its Latin counterpart (e.g. ą between a and b), ź and ż are placed after z in that order. The Slovak alphabet uses the acute (á é í ó ú ý ĺ ŕ), caron (č ď ľ ň š ť ž dž), umlaut (ä) and circumflex accent (ô). All of those are considered separate letters and are placed directly after the original counterpart in the alphabet. The basic Slovenian alphabet has the symbols č, š, and ž, which are considered separate letters and are listed as such in dictionaries and other contexts in which words are listed according to alphabetical order. Letters with a caron are placed right after the letters as written without the diacritic. The letter đ may be used in non-transliterated foreign words, particularly names, and is placed after č and before d. Turkic Azerbaijani includes the distinct Turkish alphabet letters Ç, Ğ, I, İ, Ö, Ş and Ü. Crimean Tatar includes the distinct Turkish alphabet letters Ç, Ğ, I, İ, Ö, Ş and Ü. Unlike Turkish, Crimean Tatar also has the letter Ñ. Gagauz includes the distinct Turkish alphabet letters Ç, Ğ, I, İ, Ö and Ü. Unlike Turkish, Gagauz also has the letters Ä, Ê Ș and Ț. Ș and Ț are derived from the Romanian alphabet for the same sounds. Sometime the Turkish Ş may be used instead of Ș. Turkish uses a G with a breve (Ğ), two letters with an umlaut (Ö and Ü, representing two rounded front vowels), two letters with a cedilla (Ç and Ş, representing the affricate and the fricative ), and also possesses a dotted capital İ (and a dotless lowercase ı representing a high unrounded back vowel). In Turkish each of these are separate letters, rather than versions of other letters, where dotted capital İ and lower case i are the same letter, as are dotless capital I and lowercase ı. Typographically, Ç and Ş are sometimes rendered with a subdot, as in Ṣ; when a hook is used, it tends to have more a comma shape than the usual cedilla. The new Azerbaijani, Crimean Tatar, and Gagauz alphabets are based on the Turkish alphabet and its same diacriticized letters, with some additions. Turkmen includes the distinct Turkish alphabet letters Ç, Ö, Ş and Ü. In addition, Turkmen uses A with diaeresis (Ä) to represent , N with caron (Ň) to represent the velar nasal , Y with acute (Ý) to represent the palatal approximant , and Z with caron (Ž) to represent . Other Albanian has two special letters Ç and Ë upper and lowercase. They are placed next to the most similar letters in the alphabet, c and e correspondingly. Esperanto has the symbols ŭ, ĉ, ĝ, ĥ, ĵ and ŝ, which are included in the alphabet, and considered separate letters. Filipino also has the character ñ as a letter and is collated between n and o. Hawaiian uses the kahakō (macron) over vowels, although there is some disagreement over considering them as individual letters. The kahakō over a vowel can completely change the meaning of a word that is spelled the same but without the kahakō. Kurdish uses the symbols Ç, Ê, Î, Ş and Û with other 26 standard Latin alphabet symbols. Lakota alphabet uses the caron for the letters č, ȟ, ǧ, š, and ž. It also uses the acute accent for stressed vowels á, é, í, ó, ú, áŋ, íŋ, úŋ. Malay uses some diacritics such as á, ā, ç, í, ñ, ó, š, ú. Uses of diacritics was continued until late 19th century except ā and ē. Maltese uses a C, G, and Z with a dot over them (Ċ, Ġ, Ż), and also has an H with an extra horizontal bar. For uppercase H, the extra bar is written slightly above the usual bar. For lowercase H, the extra bar is written crossing the vertical, like a t, and not touching the lower part (Ħ, ħ). The above characters are considered separate letters. The letter 'c' without a dot has fallen out of use due to redundancy. 'Ċ' is pronounced like the English 'ch' and 'k' is used as a hard c as in 'cat'. 'Ż' is pronounced just like the English 'Z' as in 'Zebra', while 'Z' is used to make the sound of 'ts' in English (like 'tsunami' or 'maths'). 'Ġ' is used as a soft 'G' like in 'geometry', while the 'G' sounds like a hard 'G' like in 'log'. The digraph 'għ' (called għajn after the
characters used in computer programming to symbolise one character A directed graph, in graph theory Digraph, component of a CIA cryptonym, a covert code name As language codes in ISO 639-1 Diagraph, a combination	such as "sh" in English [in Unicode] orthographic ligature, the joining of two letters as a single glyph, such as "æ" Digraph (computing), a group of characters used in computer programming to symbolise one character A directed graph, in graph theory Digraph, component of a CIA cryptonym, a covert
non-traditional shapes. The practice has sparked, however, a good deal of debate (aesthetic, ethical, and legal) among indigenous practitioners and non-indigenous people. Decoration Didgeridoos can be painted by their maker or a dedicated artist using traditional or modern paints while others retain the natural wood grain design with minimal or no decoration. Playing A didgeridoo can be played simply by producing a vibrating sound of the lips to produce the basic drone. More advanced play involves the technique known as circular breathing. The circular breathing technique requires breathing in through the nose whilst simultaneously using the muscles of the cheeks to compress the cheeks and expel stored air out of the mouth. By use of this technique, a skilled player can replenish the air in their lungs, and with practice can sustain a note for as long as desired. Recordings exist of modern didgeridoo players playing continuously for more than 40 minutes; Mark Atkins on Didgeridoo Concerto (1994) plays for over 50 minutes continuously. While circular breathing does eliminate the need to stop playing due to oxygen replenishment restrictions being obviated, discomfort might still develop during a period of extended play due to chapped lips or other oral discomfort. The didgeridoo functions "...as an aural kaleidoscope of timbres" and "the extremely difficult virtuoso techniques developed by expert performers find no parallel elsewhere." The didjeridu virtuoso and composer William Barton has expanded the role of the instrument in the concert hall both with his own orchestral and chamber music works and with those written or arranged for him by prominent Australian composer Peter Sculthorpe. Physics and operation A termite-bored didgeridoo has an irregular shape that, overall, usually increases in diameter towards the lower end. This shape means that its resonances occur at frequencies that are not harmonically spaced in frequency. This contrasts with the harmonic spacing of the resonances in a cylindrical plastic pipe, whose resonant frequencies fall in the ratio 1:3:5 etc. The second resonance of a didgeridoo (the note sounded by overblowing) is usually around an 11th higher than the fundamental frequency (a frequency ratio of 8:3). The vibration produced by the player's lips has harmonics, i.e., it has frequency components falling exactly in the ratio 1:2:3 etc. However, the non-harmonic spacing of the instrument's resonances means that the harmonics of the fundamental note are not systematically assisted by instrument resonances, as is usually the case for Western wind instruments (e.g., in the low range of the clarinet, the 1st, 3rd, and 5th harmonics of the reed are assisted by resonances of the bore). Sufficiently strong resonances of the vocal tract can strongly influence the timbre of the instrument. At some frequencies, whose values depend on the position of the player's tongue, resonances of the vocal tract inhibit the oscillatory flow of air into the instrument. Bands of frequencies that are not thus inhibited produce formants in the output sound. These formants, and especially their variation during the inhalation and exhalation phases of circular breathing, give the instrument its readily recognizable sound. Other variations in the didgeridoo's sound can be made by adding vocalizations to the drone. Most of the vocalizations are related to sounds emitted by Australian animals, such as the dingo or the kookaburra. To produce these sounds, the players use their vocal folds to produce the sounds of the animals whilst continuing to blow air through the instrument. The results range from very high-pitched sounds to much lower sounds involving interference between the lip and vocal fold vibrations. Adding vocalizations increases the complexity of the playing. In popular culture Charlie McMahon, who formed the group Gondwanaland, was one of the first non-Aboriginal players to gain fame as a professional didgeridoo player. He has toured internationally with Midnight Oil. He invented the didjeribone, a sliding didgeridoo made from two lengths of plastic tubing; its playing style is somewhat in the manner of a trombone. The didgeridoo has been used by a number of modern bands in various types of music. Some examples include: It was featured on the British children's TV series Blue Peter. Industrial music bands like Test Dept. Early songs by the acid jazz band Jamiroquai featured didgeridoo player Wallis Buchanan, including the band's first single "When You Gonna Learn", which features prominent didgeridoo in the introduction and solo sections. Ambient artist Steve Roach uses it in his collaborative work Australia: Sound of the Earth with Australian Aboriginal artist David Hudson and cellist Sarah Hopkins, as well as Dreamtime Return. It is used in the Indian song "Jaane Kyon" from the film Dil Chahta Hai. Chris Brooks, lead singer of the New Zealand hard rock band Like a Storm uses the didgeridoo in some songs including "Love the Way You Hate Me" from their album Chaos Theory: Part 1. Kate Bush made extensive use of the didgeridoo played by Australian musician Rolf Harris on her album The Dreaming, which was written and recorded after a holiday in Australia. Cultural significance Traditionally, the didgeridoo was played as an accompaniment to ceremonial dancing and singing and for solo or recreational purposes. For Aboriginal peoples of northern Australia, the yidaki is still used to accompany singers and dancers in cultural ceremonies. For the Yolngu people, the yidaki is part of their whole physical and cultural landscape and environment, comprising the people and spirit beings which belong to their country, kinship system and the Yolngu Matha language. It is connected to Yolngu Law and underpinned by ceremony, in song, dance, visual art and stories. Pair sticks, sometimes called clapsticks (bilma or bimla by some traditional groups), establish the beat for the songs during ceremonies. The rhythm of the didgeridoo and the beat of the clapsticks are precise, and these patterns have been handed down for many generations. In the Wangga genre, the song-man starts with vocals and then introduces bilma to the accompaniment of didgeridoo. Gender-based traditional prohibition debate Traditionally, only men play the didgeridoo and sing during ceremonial occasions and playing by females is sometimes discouraged by Aboriginal communities and elders. In 2008, publisher Harper Collins apologized for its book The Daring Book for Girls, which openly encouraged girls to play the instrument after Aboriginal academic Mark Rose described such encouragement as "extreme cultural insensitivity" and "an extreme faux pas... part of a general ignorance that mainstream Australia has about Aboriginal culture." However, Linda Barwick, an ethnomusicologist, says that though traditionally women have not played the didgeridoo in ceremony, in informal situations there is no prohibition in the Dreaming Law. For example, Jemima Wimalu, a Mara woman from the Roper River is very proficient at playing the didgeridoo and is featured on the record Aboriginal Sound Instruments released in 1978. In 1995, musicologist Steve Knopoff observed Yirrkala women performing djatpangarri songs that are traditionally performed by men and in 1996, ethnomusicologist Elizabeth MacKinley reported women of the Yanyuwa group giving public performances. While there is no prohibition in the area of the didgeridoo's origin, such restrictions have been applied by other Indigenous communities. The didgeridoo was introduced to the Kimberleys	the fundamental frequency (a frequency ratio of 8:3). The vibration produced by the player's lips has harmonics, i.e., it has frequency components falling exactly in the ratio 1:2:3 etc. However, the non-harmonic spacing of the instrument's resonances means that the harmonics of the fundamental note are not systematically assisted by instrument resonances, as is usually the case for Western wind instruments (e.g., in the low range of the clarinet, the 1st, 3rd, and 5th harmonics of the reed are assisted by resonances of the bore). Sufficiently strong resonances of the vocal tract can strongly influence the timbre of the instrument. At some frequencies, whose values depend on the position of the player's tongue, resonances of the vocal tract inhibit the oscillatory flow of air into the instrument. Bands of frequencies that are not thus inhibited produce formants in the output sound. These formants, and especially their variation during the inhalation and exhalation phases of circular breathing, give the instrument its readily recognizable sound. Other variations in the didgeridoo's sound can be made by adding vocalizations to the drone. Most of the vocalizations are related to sounds emitted by Australian animals, such as the dingo or the kookaburra. To produce these sounds, the players use their vocal folds to produce the sounds of the animals whilst continuing to blow air through the instrument. The results range from very high-pitched sounds to much lower sounds involving interference between the lip and vocal fold vibrations. Adding vocalizations increases the complexity of the playing. In popular culture Charlie McMahon, who formed the group Gondwanaland, was one of the first non-Aboriginal players to gain fame as a professional didgeridoo player. He has toured internationally with Midnight Oil. He invented the didjeribone, a sliding didgeridoo made from two lengths of plastic tubing; its playing style is somewhat in the manner of a trombone. The didgeridoo has been used by a number of modern bands in various types of music. Some examples include: It was featured on the British children's TV series Blue Peter. Industrial music bands like Test Dept. Early songs by the acid jazz band Jamiroquai featured didgeridoo player Wallis Buchanan, including the band's first single "When You Gonna Learn", which features prominent didgeridoo in the introduction and solo sections. Ambient artist Steve Roach uses it in his collaborative work Australia: Sound of the Earth with Australian Aboriginal artist David Hudson and cellist Sarah Hopkins, as well as Dreamtime Return. It is used in the Indian song "Jaane Kyon" from the film Dil Chahta Hai. Chris Brooks, lead singer of the New Zealand hard rock band Like a Storm uses the didgeridoo in some songs including "Love the Way You Hate Me" from their album Chaos Theory: Part 1. Kate Bush made extensive use of the didgeridoo played by Australian musician Rolf Harris on her album The Dreaming, which was written and recorded after a holiday in Australia. Cultural significance Traditionally, the didgeridoo was played as an accompaniment to ceremonial dancing and singing and for solo or recreational purposes. For Aboriginal peoples of northern Australia, the yidaki is still used to accompany singers and dancers in cultural ceremonies. For the Yolngu people, the yidaki is part of their whole physical and cultural landscape and environment, comprising the people and spirit beings which belong to their country, kinship system and the Yolngu Matha language. It is connected to Yolngu Law and underpinned by ceremony, in song, dance, visual art and stories. Pair sticks, sometimes called clapsticks (bilma or bimla by some traditional groups), establish the beat for the songs during ceremonies. The rhythm of the didgeridoo and the beat of the clapsticks are precise, and these patterns have been handed down for many generations. In the Wangga genre, the song-man starts with vocals and then introduces bilma to the accompaniment of didgeridoo. Gender-based traditional prohibition debate Traditionally, only men play the didgeridoo and sing during ceremonial occasions and playing by females is sometimes discouraged by Aboriginal communities and elders. In 2008, publisher Harper Collins apologized for its book The Daring Book for Girls, which openly encouraged girls to play the instrument after Aboriginal academic Mark Rose described such encouragement as "extreme cultural insensitivity" and "an extreme faux pas... part of a general ignorance that mainstream Australia has about Aboriginal culture." However, Linda Barwick, an ethnomusicologist, says that though traditionally women have not played the didgeridoo in ceremony, in informal situations there is no prohibition in the Dreaming Law. For example, Jemima Wimalu, a Mara woman from the Roper River is very proficient at playing the didgeridoo and is featured on the record Aboriginal Sound Instruments released in 1978. In 1995, musicologist Steve Knopoff observed Yirrkala women performing djatpangarri songs that are traditionally performed by men and in 1996, ethnomusicologist Elizabeth MacKinley reported women of the Yanyuwa group giving public performances. While there is no prohibition in the area of the didgeridoo's origin, such restrictions have been applied by other Indigenous communities. The didgeridoo was introduced to the Kimberleys in the early 20th century but it was only much later, such as in Rose's 2008 criticism of The Daring Book for Girls, that Aboriginal men showed adverse reactions to women playing the instrument and prohibitions are especially evident in the South East of Australia. The belief that women are prohibited from playing is widespread among non-Aboriginal people and is also common among Aboriginal communities in Southern Australia; some ethnomusicologists believe that the dissemination of the taboo belief and other misconceptions is a result of commercial agendas and marketing. The majority of commercial didgeridoo recordings available are distributed by multinational recording companies and feature non-Aboriginal people playing a New Age style of music with liner notes promoting the instrument's spirituality which misleads consumers about the didgeridoo's secular role in traditional Aboriginal culture. The taboo is particularly strong among many Aboriginal groups in the South East of Australia, where it is forbidden and considered "cultural theft" for non-Aboriginal women, and especially performers of New Age music regardless of gender, to play or even
signals active in the embryo. There is still debate about the old question of whether regeneration is a "pristine" or an "adaptive" property. If the former is the case, with improved knowledge, we might expect to be able to improve regenerative ability in humans. If the latter, then each instance of regeneration is presumed to have arisen by natural selection in circumstances particular to the species, so no general rules would be expected. Embryonic development of animals The sperm and egg fuse in the process of fertilization to form a fertilized egg, or zygote. This undergoes a period of divisions to form a ball or sheet of similar cells called a blastula or blastoderm. These cell divisions are usually rapid with no growth so the daughter cells are half the size of the mother cell and the whole embryo stays about the same size. They are called cleavage divisions. Mouse epiblast primordial germ cells (see Figure: “The initial stages of human embryogenesis”) undergo extensive epigenetic reprogramming. This process involves genome-wide DNA demethylation, chromatin reorganization and epigenetic imprint erasure leading to totipotency. DNA demethylation is carried out by a process that utilizes the DNA base excision repair pathway. Morphogenetic movements convert the cell mass into a three layered structure consisting of multicellular sheets called ectoderm, mesoderm and endoderm. These sheets are known as germ layers. This is the process of gastrulation. During cleavage and gastrulation the first regional specification events occur. In addition to the formation of the three germ layers themselves, these often generate extraembryonic structures, such as the mammalian placenta, needed for support and nutrition of the embryo, and also establish differences of commitment along the anteroposterior axis (head, trunk and tail). Regional specification is initiated by the presence of cytoplasmic determinants in one part of the zygote. The cells that contain the determinant become a signaling center and emit an inducing factor. Because the inducing factor is produced in one place, diffuses away, and decays, it forms a concentration gradient, high near the source cells and low further away. The remaining cells of the embryo, which do not contain the determinant, are competent to respond to different concentrations by upregulating specific developmental control genes. This results in a series of zones becoming set up, arranged at progressively greater distance from the signaling center. In each zone a different combination of developmental control genes is upregulated. These genes encode transcription factors which upregulate new combinations of gene activity in each region. Among other functions, these transcription factors control expression of genes conferring specific adhesive and motility properties on the cells in which they are active. Because of these different morphogenetic properties, the cells of each germ layer move to form sheets such that the ectoderm ends up on the outside, mesoderm in the middle, and endoderm on the inside. Morphogenetic movements not only change the shape and structure of the embryo, but by bringing cell sheets into new spatial relationships they also make possible new phases of signaling and response between them. Growth in embryos is mostly autonomous. For each territory of cells the growth rate is controlled by the combination of genes that are active. Free-living embryos do not grow in mass as they have no external food supply. But embryos fed by a placenta or extraembryonic yolk supply can grow very fast, and changes to relative growth rate between parts in these organisms help to produce the final overall anatomy. The whole process needs to be coordinated in time and how this is controlled is not understood. There may be a master clock able to communicate with all parts of the embryo that controls the course of events, or timing may depend simply on local causal sequences of events. Metamorphosis Developmental processes are very evident during the process of metamorphosis. This occurs in various types of animal. Well-known examples are seen in frogs, which usually hatch as a tadpole and metamorphoses to an adult frog, and certain insects which hatch as a larva and then become remodeled to the adult form during a pupal stage. All the developmental processes listed above occur during metamorphosis. Examples that have been especially well studied include tail loss and other changes in the tadpole of the frog Xenopus, and the biology of the imaginal discs, which generate the adult body parts of the fly Drosophila melanogaster. Plant development Plant development is the process by which structures originate and mature as a plant grows. It is studied in plant anatomy and plant physiology as well as plant morphology. Plants constantly produce new tissues and structures throughout their life from meristems located at the tips of organs, or between mature tissues. Thus, a living plant always has embryonic tissues. By contrast, an animal embryo will very early produce all of the body parts that it will ever have in its life. When the animal is born (or hatches from its egg), it has all its body parts and from that point will only grow larger and more mature. The properties of organization seen in a plant are emergent properties which are more than the sum of the individual parts. "The assembly of these tissues and functions into an integrated multicellular organism yields not only the characteristics of the separate parts and processes but also quite a new set of characteristics which would not have been predictable on the basis of examination of the separate parts." Growth A vascular plant begins from a single celled zygote, formed by fertilisation of an egg cell by a sperm cell. From that point, it begins to divide to form a plant embryo through the process of embryogenesis. As this happens, the resulting cells will organize so that one end becomes the first root, while the other end forms the tip of the shoot. In seed plants, the embryo will develop one or more "seed leaves" (cotyledons). By the end of embryogenesis, the young plant will have all the parts necessary to begin its life. Once the embryo germinates from its seed or parent plant, it begins to produce additional organs (leaves, stems, and roots) through the process	roots) through the process of organogenesis. New roots grow from root meristems located at the tip of the root, and new stems and leaves grow from shoot meristems located at the tip of the shoot. Branching occurs when small clumps of cells left behind by the meristem, and which have not yet undergone cellular differentiation to form a specialized tissue, begin to grow as the tip of a new root or shoot. Growth from any such meristem at the tip of a root or shoot is termed primary growth and results in the lengthening of that root or shoot. Secondary growth results in widening of a root or shoot from divisions of cells in a cambium. In addition to growth by cell division, a plant may grow through cell elongation. This occurs when individual cells or groups of cells grow longer. Not all plant cells will grow to the same length. When cells on one side of a stem grow longer and faster than cells on the other side, the stem will bend to the side of the slower growing cells as a result. This directional growth can occur via a plant's response to a particular stimulus, such as light (phototropism), gravity (gravitropism), water, (hydrotropism), and physical contact (thigmotropism). Plant growth and development are mediated by specific plant hormones and plant growth regulators (PGRs) (Ross et al. 1983). Endogenous hormone levels are influenced by plant age, cold hardiness, dormancy, and other metabolic conditions; photoperiod, drought, temperature, and other external environmental conditions; and exogenous sources of PGRs, e.g., externally applied and of rhizospheric origin. Morphological variation Plants exhibit natural variation in their form and structure. While all organisms vary from individual to individual, plants exhibit an additional type of variation. Within a single individual, parts are repeated which may differ in form and structure from other similar parts. This variation is most easily seen in the leaves of a plant, though other organs such as stems and flowers may show similar variation. There are three primary causes of this variation: positional effects, environmental effects, and juvenility. Evolution of plant morphology Transcription factors and transcriptional regulatory networks play key roles in plant morphogenesis and their evolution. During plant landing, many novel transcription factor families emerged and are preferentially wired into the networks of multicellular development, reproduction, and organ development, contributing to more complex morphogenesis of land plants. Most land plants share a common ancestor, multicellular algae. An example of the evolution of plant morphology is seen in charophytes. Studies have shown that charophytes have traits that are homologous to land plants. There are two main theories of the evolution of plant morphology, these theories are the homologous theory and the antithetic theory. The commonly accepted theory for the evolution of plant morphology is the antithetic theory. The antithetic theory states that the multiple mitotic divisions that take place before meiosis, cause the development of the sporophyte. Then the sporophyte will development as an independent organism. Developmental model organisms Much of developmental biology research in recent decades has focused on the use of a small number of model organisms. It has turned out that there is much conservation of developmental mechanisms across the animal kingdom. In early development different vertebrate species all use essentially the same inductive signals and the same genes encoding regional identity. Even invertebrates use a similar repertoire of signals and genes although the body parts formed are significantly different. Model organisms each have some particular experimental advantages which have enabled them to become popular among researchers. In one sense they are "models" for the whole animal kingdom, and in another sense they are "models" for human development, which is difficult to study directly for both ethical and practical reasons. Model organisms have been most useful for elucidating the broad nature of developmental mechanisms. The more detail is sought, the more they differ from each other and from humans. Plants Thale cress (Arabidopsis thaliana) Vertebrates Frog: Xenopus (X. laevis and X. tropicalis). Good embryo supply. Especially suitable for microsurgery. Zebrafish: Danio rerio. Good embryo supply. Well developed genetics. Chicken: Gallus gallus. Early stages similar to mammal, but microsurgery easier. Low cost. Mouse: Mus musculus. A mammal with well developed genetics. Invertebrates Fruit fly: Drosophila melanogaster. Good embryo supply. Well developed genetics. Nematode: Caenorhabditis elegans. Good embryo supply. Well developed genetics. Low cost. Unicellular Algae: Chlamydomonas Yeast: Saccharomyces Others Also popular for some purposes have been sea urchins and ascidians. For studies of regeneration urodele amphibians such as the axolotl Ambystoma mexicanum are used, and also planarian worms such as Schmidtea mediterranea. Organoids have also been demonstrated as an efficient model for development. Plant development has focused on the thale cress Arabidopsis thaliana as a model organism. See also References Further
playwright 1952 – Jay Hill, Canadian farmer and politician 1952 – David Knopfler, Scottish singer-songwriter, guitarist, and producer 1954 – Edmund Zagorski, American convicted murderer (d. 2018) 1954 – Mandie Fletcher, English director, producer, and production manager 1954 – Teo Chee Hean, Singaporean politician and 5th Senior Minister of Singapore 1955 – Brad Murphey, American race car driver 1955 – Barbara Olson, American journalist and author (d. 2001) 1956 – Doina Melinte, Romanian runner 1958 – Steve Jones, American golfer 1959 – Gerina Dunwich, American astrologer, historian, and author 1959 – Andre Tippett, American football player and coach 1960 – Maryam d'Abo, English actress 1960 – Donald Nally, American conductor and academic 1960 – Terry Price, Australian golfer 1961 – Guido Westerwelle, German lawyer and politician, 15th Vice-Chancellor of Germany (d. 2016) 1962 – Mark Few, American basketball player and coach 1962 – John Kampfner, Singaporean journalist and author 1962 – Bill Self, American basketball player and coach 1962 – Sherri Steinhauer, American golfer 1963 – Gaspar Noé, Argentinian-French director and screenwriter 1965 – Chris Mainwaring, Australian footballer and journalist (d. 2007) 1965 – Salman Khan, Indian film actor and producer 1966 – Marianne Elliott, English director and producer 1966 – Bill Goldberg, American football player, wrestler and actor 1966 – Eva LaRue, American model and actress 1966 – Fabian Núñez, American politician 1969 – Jean-Christophe Boullion, French race car driver 1969 – Sarah Vowell, American author and journalist 1969 – Chyna, American professional wrestler and actress (d. 2016) 1970 – Brendon Cook, Australian race car driver and rugby player 1970 – Lorenzo Neal, American football player and radio host 1971 – Duncan Ferguson, Scottish footballer and coach 1971 – Guthrie Govan, English guitarist and educator 1971 – Savannah Guthrie, American television journalist 1971 – Jason Hawes, American paranormal investigator and author, founded The Atlantic Paranormal Society 1971 – Bryan Smolinski, American ice hockey player and coach 1972 – Colin Charvis, Welsh rugby union player and coach 1972 – Kevin Ollie, American basketball player and coach 1972 – Matt Slocum, American guitarist and songwriter 1973 – Kristoffer Zegers, Dutch pianist and composer 1974 – Tomáš Janků, Czech high jumper 1974 – Masi Oka, Japanese-American actor and visual effects designer 1974 – Fumiko Orikasa, Japanese voice actress and singer 1974 – Jay Pandolfo, American ice hockey player and coach 1975 – Aigars Fadejevs, Latvian race walker and therapist 1975 – Kjell Eriksson, Swedish television personality 1975 – Heather O'Rourke, American actress (d. 1988) 1976 – Nikolaos Georgeas, Greek footballer 1976 – Piotr Morawski, Polish mountaineer (d. 2009) 1976 – Daimí Pernía, Cuban basketball player and hurdler 1976 – Fernando Pisani, Canadian-Italian ice hockey player 1977 – Jacqueline Pillon, Canadian actress 1977 – Chris Tate, English footballer 1978 – Deuce McAllister, American football player 1979 – Pascale Dorcelus, Canadian weightlifter 1979 – David Dunn, English footballer and manager 1979 – Carson Palmer, American football player 1980 – Bernard Berrian, American football player 1980 – Cesaro, Swiss professional wrestler 1980 – Dahntay Jones, American basketball player 1980 – Meelis Kompus, Estonian journalist 1981 – David Aardsma, American baseball player 1981 – Emilie de Ravin, Australian actress 1981 – Moise Joseph, American-Haitian runner 1981 – Patrick Sharp, Canadian ice hockey player 1982 – Erin E. Stead, American illustrator 1983 – Anthony Boric, New Zealand rugby union player 1983 – Cole Hamels, American baseball player 1983 – Jesse Williams, American high jumper 1984 – Andrejs Perepļotkins, Ukrainian-Latvian footballer 1984 – Gilles Simon, French tennis player 1985 – Logan Bailly, Belgian footballer 1985 – Jérôme d'Ambrosio, Belgian race car driver 1985 – Paul Stastny, Canadian-American ice hockey player 1985 – Halley Gross, American screenwriter 1986 – Torah Bright, Australian snowboarder 1986 – Shelly-Ann Fraser-Pryce, Jamaican sprinter 1987 – Tim Browne, Australian rugby league player 1987 – Lily Cole, English model 1988 – Hera Hilmar, Icelandic actress 1988 – Zavon Hines, Jamaican-English footballer 1988 – Ok Taec-yeon, South Korean singer and actor 1988 – Rick Porcello, American baseball player 1988 – Hayley Williams, American singer-songwriter 1989 – Ingrid Várgas Calvo, Peruvian tennis player 1990 – Max Lindholm, Finnish figure skater 1990 – Milos Raonic, Canadian tennis player 1990 – Jon Marchessault, Canadian ice hockey player 1991 – Michael Morgan, Australian rugby league player 1991 – Danny Wilson, Scottish footballer 1992 – Joel Indermitte, Estonian footballer 1992 – Maicel Uibo, Estonian decathlete 1993 – Olivia Cooke, English actress 1995 – Timothée Chalamet, American actor 1995 – Mark Lapidus, Estonian chess player 1997 – Ana Konjuh, Croatian tennis player 1997 – Vachirawit Chiva-aree, Thai actor and singer Deaths Pre-1600 683 – Gaozong of Tang, founding emperor of the Chinese Tang dynasty (b. 628) 870 – Aeneas of Paris, Frankish bishop 975 – Balderic, bishop of Utrecht (b. 897) 1003 – Emma of Blois, French duchess and regent 1005 – Nilus the Younger, Byzantine abbot (b. 910) 1076 – Sviatoslav II, Grand Prince of Kiev (b. 1027) 1087 – Bertha of Savoy, Holy Roman Empress (b. 1051) 1381 – Edmund Mortimer, 3rd Earl of March, English politician (b. 1352) 1518 – Mahmood Shah Bahmani II, sultan of the Bahmani Sultanate (b. c. 1470) 1543 – George, margrave of Brandenburg-Ansbach (b. 1484) 1548 – Francesco Spiera, Italian lawyer and jurist (b. 1502) 1601–1900 1603 – Thomas Cartwright, English minister and theologian (b. 1535) 1656 – Andrew White, English Jesuit missionary (b. 1579) 1704 – Hans Albrecht von Barfus, Prussian field marshal and politician (b. 1635) 1707 – Jean Mabillon, French monk and scholar (b. 1632) 1737 – William Bowyer, English printer (b. 1663) 1743 – Hyacinthe Rigaud, French painter (b. 1659) 1771 – Henri Pitot, French engineer, invented the Pitot tube (b. 1695) 1776 – Johann Rall, Hessian colonel (b. ) 1782 – Henry Home, Lord Kames, Scottish judge and philosopher (b. 1697) 1800 – Hugh Blair, Scottish minister and author (b. 1718) 1812 – Joanna Southcott, English religious leader (b. 1750) 1834 – Charles Lamb, English essayist and poet (b. 1775) 1836 – Stephen F. Austin, American soldier and politician (b. 1793) 1858 – Alexandre Pierre François Boëly, French pianist and composer (b. 1785) 1896 – John Brown, English businessman and politician (b. 1816) 1900 – William Armstrong, 1st Baron Armstrong, English engineer and businessman, founded Armstrong Whitworth (b. 1810) 1901–present 1914 – Charles Martin Hall, American chemist and engineer (b. 1863) 1919 – Achilles Alferaki, Russian-Greek composer and politician, Governor of Taganrog (b. 1846) 1923 – Gustave Eiffel, French architect and engineer, co-designed the Eiffel Tower (b. 1832) 1924 – Agda Meyerson, Swedish nurse and healthcare activist (b. 1866) 1936 – Mehmet Akif Ersoy, Turkish poet, academic, and politician (b. 1873) 1938 – Calvin Bridges, American geneticist and academic (b. 1889) 1938 – Osip Mandelstam, Polish-Russian poet and critic (b. 1891) 1938 – Zona Gale, American novelist, short story writer, and playwright (b. 1874) 1939 – Rinaldo Cuneo, American painter (b. 1877) 1943 – Ants Kurvits, Estonian general and politician, 10th Estonian Minister of War (b. 1887) 1950 – Max Beckmann, German-American painter and sculptor (b. 1884) 1952 – Patrick Joseph Hartigan, Australian priest, author, and educator (b. 1878) 1953 – Şükrü Saracoğlu, Turkish soldier and politician, 6th Prime Minister of Turkey (b. 1887) 1953 – Julian Tuwim, Polish poet and author (b. 1894) 1955 – Alfred Carpenter, English admiral, Victoria Cross recipient (b. 1881) 1956 – Lambert McKenna, Irish priest and lexicographer (b. 1870) 1965 – Edgar Ende, German painter (b. 1901) 1972 – Lester B. Pearson, Canadian historian and politician, 14th Prime Minister of Canada, Nobel Prize laureate (b. 1897) 1974 – Vladimir Fock, Russian physicist and mathematician (b. 1898) 1974 – Amy Vanderbilt, American author (b. 1908) 1978 – Chris Bell, American singer-songwriter and guitarist (b. 1951) 1978 – Houari Boumediene, Algerian colonel and politician, 2nd President of Algeria (b. 1932) 1978 – Bob Luman, American singer-songwriter and guitarist (b. 1937) 1979 – Hafizullah Amin, Afghan educator and politician, 2nd General Secretary of the People's Democratic Party of Afghanistan (b. 1929) 1981 – Hoagy Carmichael, American singer-songwriter, pianist, and actor (b. 1899) 1982 – Jack Swigert, American pilot, astronaut, and politician (b. 1931) 1985 – Jean Rondeau, French race car driver (b. 1946) 1986 – George Dangerfield, English-American historian and journalist (b. 1904) 1986 – Dumas Malone, American historian and author (b. 1892) 1987 – Rewi Alley, New Zealand writer and political activist (b. 1897) 1988 – Hal Ashby, American director and producer (b. 1929) 1992 – Kay Boyle, American novelist, poet, and educator (b. 1902) 1993 – Feliks Kibbermann, Estonian chess player and philologist (b. 1902) 1993 – Evald Mikson, Estonian footballer (b. 1911) 1993 – André Pilette, Belgian race car driver (b. 1918) 1994 – Fanny Cradock, English author and critic (b. 1909) 1994 – J. B. L. Reyes, Filipino lawyer and jurist (b. 1902) 1995 – Shura Cherkassky, Ukrainian-American pianist (b. 1909) 1995 – Genrikh Kasparyan, Armenian chess player and composer (b. 1910) 1997 – Brendan Gill, American journalist and essayist (b. 1914) 1997 – Billy Wright, Northern Irish loyalist leader (b. 1960) 1999 – Michael McDowell, American author and screenwriter (b. 1950) 2002 – George Roy Hill, American actor, director, producer, and screenwriter (b. 1922) 2003 – Alan Bates, English actor (b. 1934) 2003 – Iván Calderón, Puerto Rican-American baseball player (b. 1962) 2004 – Hank Garland, American guitarist (b. 1930) 2007 – Benazir Bhutto, Pakistani politician, Prime Minister of Pakistan (b. 1953) 2007 – Jerzy Kawalerowicz, Polish director and screenwriter (b. 1922) 2007 – Jaan Kross, Estonian author and poet (b. 1920) 2008 – Delaney Bramlett, American singer-songwriter, guitarist, and producer (b. 1939) 2008 – Robert Graham, Mexican-American sculptor (b. 1938) 2009 – Isaac Schwartz, Ukrainian-Russian composer and educator (b. 1923) 2011	player 1997 – Vachirawit Chiva-aree, Thai actor and singer Deaths Pre-1600 683 – Gaozong of Tang, founding emperor of the Chinese Tang dynasty (b. 628) 870 – Aeneas of Paris, Frankish bishop 975 – Balderic, bishop of Utrecht (b. 897) 1003 – Emma of Blois, French duchess and regent 1005 – Nilus the Younger, Byzantine abbot (b. 910) 1076 – Sviatoslav II, Grand Prince of Kiev (b. 1027) 1087 – Bertha of Savoy, Holy Roman Empress (b. 1051) 1381 – Edmund Mortimer, 3rd Earl of March, English politician (b. 1352) 1518 – Mahmood Shah Bahmani II, sultan of the Bahmani Sultanate (b. c. 1470) 1543 – George, margrave of Brandenburg-Ansbach (b. 1484) 1548 – Francesco Spiera, Italian lawyer and jurist (b. 1502) 1601–1900 1603 – Thomas Cartwright, English minister and theologian (b. 1535) 1656 – Andrew White, English Jesuit missionary (b. 1579) 1704 – Hans Albrecht von Barfus, Prussian field marshal and politician (b. 1635) 1707 – Jean Mabillon, French monk and scholar (b. 1632) 1737 – William Bowyer, English printer (b. 1663) 1743 – Hyacinthe Rigaud, French painter (b. 1659) 1771 – Henri Pitot, French engineer, invented the Pitot tube (b. 1695) 1776 – Johann Rall, Hessian colonel (b. ) 1782 – Henry Home, Lord Kames, Scottish judge and philosopher (b. 1697) 1800 – Hugh Blair, Scottish minister and author (b. 1718) 1812 – Joanna Southcott, English religious leader (b. 1750) 1834 – Charles Lamb, English essayist and poet (b. 1775) 1836 – Stephen F. Austin, American soldier and politician (b. 1793) 1858 – Alexandre Pierre François Boëly, French pianist and composer (b. 1785) 1896 – John Brown, English businessman and politician (b. 1816) 1900 – William Armstrong, 1st Baron Armstrong, English engineer and businessman, founded Armstrong Whitworth (b. 1810) 1901–present 1914 – Charles Martin Hall, American chemist and engineer (b. 1863) 1919 – Achilles Alferaki, Russian-Greek composer and politician, Governor of Taganrog (b. 1846) 1923 – Gustave Eiffel, French architect and engineer, co-designed the Eiffel Tower (b. 1832) 1924 – Agda Meyerson, Swedish nurse and healthcare activist (b. 1866) 1936 – Mehmet Akif Ersoy, Turkish poet, academic, and politician (b. 1873) 1938 – Calvin Bridges, American geneticist and academic (b. 1889) 1938 – Osip Mandelstam, Polish-Russian poet and critic (b. 1891) 1938 – Zona Gale, American novelist, short story writer, and playwright (b. 1874) 1939 – Rinaldo Cuneo, American painter (b. 1877) 1943 – Ants Kurvits, Estonian general and politician, 10th Estonian Minister of War (b. 1887) 1950 – Max Beckmann, German-American painter and sculptor (b. 1884) 1952 – Patrick Joseph Hartigan, Australian priest, author, and educator (b. 1878) 1953 – Şükrü Saracoğlu, Turkish soldier and politician, 6th Prime Minister of Turkey (b. 1887) 1953 – Julian Tuwim, Polish poet and author (b. 1894) 1955 – Alfred Carpenter, English admiral, Victoria Cross recipient (b. 1881) 1956 – Lambert McKenna, Irish priest and lexicographer (b. 1870) 1965 – Edgar Ende, German painter (b. 1901) 1972 – Lester B. Pearson, Canadian historian and politician, 14th Prime Minister of Canada, Nobel Prize laureate (b. 1897) 1974 – Vladimir Fock, Russian physicist and mathematician (b. 1898) 1974 – Amy Vanderbilt, American author (b. 1908) 1978 – Chris Bell, American singer-songwriter and guitarist (b. 1951) 1978 – Houari Boumediene, Algerian colonel and politician, 2nd President of Algeria (b. 1932) 1978 – Bob Luman, American singer-songwriter and guitarist (b. 1937) 1979 – Hafizullah Amin, Afghan educator and politician, 2nd General Secretary of the People's Democratic Party of Afghanistan (b. 1929) 1981 – Hoagy Carmichael, American singer-songwriter, pianist, and actor (b. 1899) 1982 – Jack Swigert, American pilot, astronaut, and politician (b. 1931) 1985 – Jean Rondeau, French race car driver (b. 1946) 1986 – George Dangerfield, English-American historian and journalist (b. 1904) 1986 – Dumas Malone, American historian and author (b. 1892) 1987 – Rewi Alley, New Zealand writer and political activist (b. 1897) 1988 – Hal Ashby, American director and producer (b. 1929) 1992 – Kay Boyle, American novelist, poet, and educator (b. 1902) 1993 – Feliks Kibbermann, Estonian chess player and philologist (b. 1902) 1993 – Evald Mikson, Estonian footballer (b. 1911) 1993 – André Pilette, Belgian race car driver (b. 1918) 1994 – Fanny Cradock, English author and critic (b. 1909) 1994 – J. B. L. Reyes, Filipino lawyer and jurist (b. 1902) 1995 – Shura Cherkassky, Ukrainian-American pianist (b. 1909) 1995 – Genrikh Kasparyan, Armenian chess player and composer (b. 1910) 1997 – Brendan Gill, American journalist and essayist (b. 1914) 1997 – Billy Wright, Northern Irish loyalist leader (b. 1960) 1999 – Michael McDowell, American author and screenwriter (b. 1950) 2002 – George Roy Hill, American actor, director, producer, and screenwriter (b. 1922) 2003 – Alan Bates, English actor (b. 1934) 2003 – Iván Calderón, Puerto Rican-American baseball player (b. 1962) 2004 – Hank Garland, American guitarist (b. 1930) 2007 – Benazir Bhutto, Pakistani politician, Prime Minister of Pakistan (b. 1953) 2007 – Jerzy Kawalerowicz, Polish director and screenwriter (b. 1922) 2007 – Jaan Kross, Estonian author and poet (b. 1920) 2008 – Delaney Bramlett, American singer-songwriter, guitarist, and producer (b. 1939) 2008 – Robert Graham, Mexican-American sculptor (b. 1938) 2009 – Isaac Schwartz, Ukrainian-Russian composer and educator (b. 1923) 2011 – Catê, Brazilian footballer and manager (b. 1973) 2011 – Michael Dummett, English soldier, philosopher, and academic (b. 1925) 2011 – Helen Frankenthaler, American painter and educator (b. 1928) 2011 – Johnny Wilson, Canadian-American ice hockey player and coach (b. 1929) 2012 – Harry Carey, Jr., American actor, producer, and screenwriter (b. 1921) 2012 – Lloyd Charmers, Jamaican singer, keyboard player, and producer (b. 1938) 2012 – Tingye Li, Chinese-American physicist and engineer (b. 1931) 2012 – Archie Roy, Scottish astronomer and academic (b. 1924) 2012 – Norman Schwarzkopf, Jr., American general and engineer (b. 1934) 2012 – Salt Walther, American race car driver (b. 1947) 2013 – Richard Ambler, English-Scottish biologist and academic (b. 1933) 2013 – Mohamad Chatah, Lebanese economist and politician, Lebanese Minister of Finance (b. 1951) 2013 – Gianna D'Angelo, American soprano and educator (b. 1929) 2013 – John Matheson, Canadian colonel, lawyer, and politician (b. 1917) 2013 – Farooq Sheikh, Indian actor, philanthropist and a popular television presenter (b. 1948) 2014 – Ben Ammi Ben-Israel, American-Israeli religious leader, founded the African Hebrew Israelites of Jerusalem (b. 1939) 2014 – Ulises Estrella, Ecuadorian poet and academic (b. 1939) 2014 – Ronald Li, Hong Kong accountant and businessman (b. 1929) 2014 – Karel Poma, Belgian bacteriologist and politician (b.
Currently, the most commonly proposed definition for a double-planet system is one in which the barycenter, around which both bodies orbit, lies outside both bodies. Under this definition, Pluto and Charon are double dwarf planets, since they orbit a point clearly outside of Pluto, as visible in animations created from images of the New Horizons space probe in June 2015. Under this definition, the Earth–Moon system is not currently a double planet; although the Moon is massive enough to cause the Earth to make a noticeable revolution around this center of mass, this point nevertheless lies well within Earth. However, the Moon currently migrates outward from Earth at a rate of approximately per year; in a few billion years, the Earth–Moon system's center of mass will lie outside Earth, which would make it a double-planet system. The center of mass of the Jupiter–Sun system lies outside the surface of the Sun, though arguing that Jupiter and the Sun are a double star is not analogous to arguing Pluto-Charon is a double dwarf planet. Jupiter is too light to be a fusor; were it thirteen times heavier, it would achieve deuterium fusion and become a brown dwarf. Tug-of-war value Isaac Asimov suggested a distinction between planet–moon and double-planet structures based in part on what he called a "tug-of-war" value, which does not consider their relative sizes. This quantity is simply the ratio of the force exerted on the smaller body by the larger (primary) body to the force exerted on the smaller body by the Sun. This can be shown to equal where is the mass of the primary (the larger body), is the mass of the Sun, is the distance between the smaller body and the Sun, and is the distance between the smaller body and the primary. The tug-of-war value does not rely on the mass of the satellite (the smaller body). This formula actually reflects the relation of the gravitational effects on the smaller body from the larger body and from the Sun. The tug-of-war figure for Saturn's moon Titan is 380, which means that Saturn's hold on Titan is 380 times as strong as the Sun's hold on Titan. Titan's tug-of-war value may be compared with that of Saturn's moon Phoebe, which has a tug-of-war value of just 3.5. So Saturn's hold on Phoebe is only 3.5 times as strong as the Sun's hold on Phoebe. Asimov calculated tug-of-war values for several satellites of the planets. He showed that even the largest gas giant, Jupiter, had only a slightly better hold than the Sun on its outer captured satellites, some with tug-of-war values not much higher than one. In nearly every one of Asimov's calculations the tug-of-war value was found to be greater than one, so in those cases the Sun loses the tug-of-war with the planets. The one exception was Earth's Moon, where the Sun wins the tug-of-war with a value of 0.46, which means that Earth's hold on the Moon is less than half that of the Sun's. Asimov included this with his other arguments that Earth and the Moon should be considered a binary planet. See the Path of Earth and Moon around Sun section in the "Orbit of the Moon" article for a more detailed explanation. This definition of double planet depends on the pair's distance from the Sun. If the Earth–Moon system happened to orbit farther away from the Sun than it does now, then Earth would win the tug of war. For example, at the orbit of Mars, the Moon's tug-of-war value would be 1.05. Also, several tiny moons discovered since Asimov's proposal would qualify as double planets by this argument. Neptune's small outer	must the mass ratio be?" Center-of-mass position Currently, the most commonly proposed definition for a double-planet system is one in which the barycenter, around which both bodies orbit, lies outside both bodies. Under this definition, Pluto and Charon are double dwarf planets, since they orbit a point clearly outside of Pluto, as visible in animations created from images of the New Horizons space probe in June 2015. Under this definition, the Earth–Moon system is not currently a double planet; although the Moon is massive enough to cause the Earth to make a noticeable revolution around this center of mass, this point nevertheless lies well within Earth. However, the Moon currently migrates outward from Earth at a rate of approximately per year; in a few billion years, the Earth–Moon system's center of mass will lie outside Earth, which would make it a double-planet system. The center of mass of the Jupiter–Sun system lies outside the surface of the Sun, though arguing that Jupiter and the Sun are a double star is not analogous to arguing Pluto-Charon is a double dwarf planet. Jupiter is too light to be a fusor; were it thirteen times heavier, it would achieve deuterium fusion and become a brown dwarf. Tug-of-war value Isaac Asimov suggested a distinction between planet–moon and double-planet structures based in part on what he called a "tug-of-war" value, which does not consider their relative sizes. This quantity is simply the ratio of the force exerted on the smaller body by the larger (primary) body to the force exerted on the smaller body by the Sun. This can be shown to equal where is the mass of the primary (the larger body), is the mass of the Sun, is the distance between the smaller body and the Sun, and is the distance between the smaller body and the primary. The tug-of-war value does not rely on the mass of the satellite (the smaller body). This formula actually reflects the relation of the gravitational effects on the smaller body from the larger body and from the Sun. The tug-of-war figure for Saturn's moon Titan is 380, which means that Saturn's hold on Titan is 380 times as strong as the Sun's hold on Titan. Titan's tug-of-war value may be compared with that of Saturn's moon Phoebe, which has a tug-of-war value of just 3.5. So Saturn's hold on Phoebe is only 3.5 times as strong as the Sun's hold on Phoebe. Asimov calculated tug-of-war values for several satellites of the planets. He showed that even the largest gas giant, Jupiter, had only
curling up on itself so that hydrophobic elements of the protein are buried deep inside the structure and hydrophilic elements end up on the outside. The final shape of a protein determines how it interacts with its environment. Protein folding consists of a balance between a substantial amount of weak intra-molecular interactions within a protein (Hydrophobic, electrostatic, and Van Der Waals Interactions) and protein-solvent interactions. As a result, this process is heavily reliant on environmental state that the protein resides in. These environmental conditions include, and are not limited to, temperature, salinity, pressure, and the solvents that happen to be involved. Consequently, any exposure to extreme stresses (e.g. heat or radiation, high inorganic salt concentrations, strong acids and bases) can disrupt a protein's interaction and inevitably lead to denaturation. When a protein is denatured, secondary and tertiary structures are altered but the peptide bonds of the primary structure between the amino acids are left intact. Since all structural levels of the protein determine its function, the protein can no longer perform its function once it has been denatured. This is in contrast to intrinsically unstructured proteins, which are unfolded in their native state, but still functionally active and tend to fold upon binding to their biological target. How denaturation occurs at levels of protein structure In quaternary structure denaturation, protein sub-units are dissociated and/or the spatial arrangement of protein subunits is disrupted. Tertiary structure denaturation involves the disruption of: Covalent interactions between amino acid side-chains (such as disulfide bridges between cysteine groups) Non-covalent dipole-dipole interactions between polar amino acid side-chains (and the surrounding solvent) Van der Waals (induced dipole) interactions between nonpolar amino acid side-chains. In secondary structure denaturation, proteins lose all regular repeating patterns such as alpha-helices and beta-pleated sheets, and adopt a random coil configuration. Primary structure, such as the sequence of amino acids held together by covalent peptide bonds, is not disrupted by denaturation. Loss of function Most biological substrates lose their biological function when denatured. For example, enzymes lose their activity, because the substrates can no longer bind to the active site, and because amino acid residues involved in stabilizing substrates' transition states are no longer positioned to be able to do so. The denaturing process and the associated loss of activity can be measured using techniques such as dual-polarization interferometry, CD, QCM-D and MP-SPR. Loss of activity due to heavy metals and metalloids By targeting proteins, heavy metals have been known to disrupt the function and activity carried out by proteins. It is important to note that heavy metals fall into categories consisting of transition metals as well as a select amount of metalloid. These metals, when interacting with native, folded proteins, tend to play a role in obstructing their biological activity. This interference can be carried out in a different number of ways. These heavy metals can form a complex with the functional side chain groups present in a protein or form bonds to free thiols. Heavy metals also play a role in oxidizing amino acid side chains present in protein. Along with this, when interacting with metalloproteins, heavy metals can dislocate and replace key metal ions. As a result, heavy metals can interfere with folded proteins, which can strongly deter protein stability and activity. Reversibility and irreversibility In many cases, denaturation is reversible (the proteins can regain their native state when the denaturing influence is removed). This process can be called renaturation. This understanding has led to the notion that all the information needed for proteins to assume their native state was encoded in the primary structure of the protein, and hence in the DNA that codes for the protein, the so-called "Anfinsen's thermodynamic hypothesis". Denaturation can also be irreversible. This irreversibility is typically a kinetic, not thermodynamic irreversibility, as a folded protein generally has lower free energy than when it is unfolded. Through kinetic irreversibility, the fact that the protein is stuck in a local minimum can stop it from ever refolding after it has been irreversibly denatured. Protein denaturation due to pH Denaturation can also be caused by changes in the pH which can affect the chemistry of the amino acids and their residues. The ionizable groups in amino acids are able to become ionized when changes in pH occur. A pH change to more acidic or more basic conditions can induce unfolding. Acid-induced unfolding often occurs between pH 2 and 5, base-induced unfolding usually requires pH 10 or higher. Nucleic acid denaturation Nucleic acids (including RNA and DNA) are nucleotide polymers synthesized by polymerase enzymes during either transcription or DNA replication. Following 5'-3' synthesis of the backbone, individual nitrogenous bases are capable of interacting with one another via hydrogen bonding, thus allowing for the formation of higher-order structures. Nucleic acid denaturation occurs when hydrogen bonding between nucleotides is disrupted, and results in the separation of previously annealed strands. For example, denaturation of DNA due to high temperatures results in the disruption of Watson and Crick base pairs and the separation of the double stranded helix into two single strands. Nucleic acid strands are capable of re-annealling when "normal" conditions are restored, but if restoration occurs too quickly, the nucleic acid strands may re-anneal imperfectly resulting in the improper pairing of bases. Biologically-induced denaturation The non-covalent interactions between antiparallel strands in DNA can be broken in order to "open" the double helix when biologically important mechanisms such as DNA replication, transcription, DNA repair or protein binding are set to occur. The area of partially separated DNA is known as the denaturation bubble, which can be more specifically defined as the opening of a DNA double helix through the coordinated separation of base pairs. The	nonpolar amino acid side-chains. In secondary structure denaturation, proteins lose all regular repeating patterns such as alpha-helices and beta-pleated sheets, and adopt a random coil configuration. Primary structure, such as the sequence of amino acids held together by covalent peptide bonds, is not disrupted by denaturation. Loss of function Most biological substrates lose their biological function when denatured. For example, enzymes lose their activity, because the substrates can no longer bind to the active site, and because amino acid residues involved in stabilizing substrates' transition states are no longer positioned to be able to do so. The denaturing process and the associated loss of activity can be measured using techniques such as dual-polarization interferometry, CD, QCM-D and MP-SPR. Loss of activity due to heavy metals and metalloids By targeting proteins, heavy metals have been known to disrupt the function and activity carried out by proteins. It is important to note that heavy metals fall into categories consisting of transition metals as well as a select amount of metalloid. These metals, when interacting with native, folded proteins, tend to play a role in obstructing their biological activity. This interference can be carried out in a different number of ways. These heavy metals can form a complex with the functional side chain groups present in a protein or form bonds to free thiols. Heavy metals also play a role in oxidizing amino acid side chains present in protein. Along with this, when interacting with metalloproteins, heavy metals can dislocate and replace key metal ions. As a result, heavy metals can interfere with folded proteins, which can strongly deter protein stability and activity. Reversibility and irreversibility In many cases, denaturation is reversible (the proteins can regain their native state when the denaturing influence is removed). This process can be called renaturation. This understanding has led to the notion that all the information needed for proteins to assume their native state was encoded in the primary structure of the protein, and hence in the DNA that codes for the protein, the so-called "Anfinsen's thermodynamic hypothesis". Denaturation can also be irreversible. This irreversibility is typically a kinetic, not thermodynamic irreversibility, as a folded protein generally has lower free energy than when it is unfolded. Through kinetic irreversibility, the fact that the protein is stuck in a local minimum can stop it from ever refolding after it has been irreversibly denatured. Protein denaturation due to pH Denaturation can also be caused by changes in the pH which can affect the chemistry of the amino acids and their residues. The ionizable groups in amino acids are able to become ionized when changes in pH occur. A pH change to more acidic or more basic conditions can induce unfolding. Acid-induced unfolding often occurs between pH 2 and 5, base-induced unfolding usually requires pH 10 or higher. Nucleic acid denaturation Nucleic acids (including RNA and DNA) are nucleotide polymers synthesized by polymerase enzymes during either transcription or DNA replication. Following 5'-3' synthesis of the backbone, individual nitrogenous bases are capable of interacting with one another via hydrogen bonding, thus allowing for the formation of higher-order structures. Nucleic acid denaturation occurs when hydrogen bonding between nucleotides is disrupted, and results in the separation of previously annealed strands. For example, denaturation of DNA due to high temperatures results in the disruption of Watson and Crick base pairs and the separation of the double stranded helix into two single strands. Nucleic acid strands are capable of re-annealling when "normal" conditions are restored, but if restoration occurs too quickly, the nucleic acid strands may re-anneal imperfectly resulting in the improper pairing of bases. Biologically-induced denaturation The non-covalent interactions between antiparallel strands in DNA can be broken in order to "open" the double helix when biologically important mechanisms such as DNA replication, transcription, DNA repair or protein binding are set to occur. The area of partially separated DNA is known as the denaturation bubble, which can be more specifically defined as the opening of a DNA double helix through the coordinated separation of base pairs. The first model that attempted to describe the thermodynamics of the denaturation bubble was introduced in 1966 and called the Poland-Scheraga Model. This model describes the denaturation of DNA strands as a function of temperature. As the temperature increases, the hydrogen bonds between the Watson and Crick base pairs are increasingly disturbed and "denatured loops" begin to form. However, the Poland-Scheraga Model is now considered elementary because it fails to account for the confounding implications of DNA sequence, chemical composition, stiffness and torsion. Recent thermodynamic studies have inferred that the lifetime of a singular denaturation bubble ranges from 1 microsecond to 1 millisecond. This information is based on established timescales of DNA replication and transcription. Currently, biophysical and biochemical research studies are
work of cross-cultural evangelism by promoting "The Wordless Book," a teaching tool developed in 1866 by Charles Spurgeon. In 1875, Moody added a fourth color to the design of the three-color evangelistic device: gold — to "represent heaven." This "book" has been and is still used to teach uncounted thousands of illiterate people, young and old, around the globe about the gospel message. Moody visited Britain with Ira D. Sankey, with Moody preaching and Sankey singing at meetings. Together they published books of Christian hymns. In 1883 they visited Edinburgh and raised £10,000 for the building of a new home for the Carrubbers Close Mission. Moody later preached at the laying of the foundation stone for what is now called the Carrubbers Christian Centre, one of the few buildings on the Royal Mile which continues to be used for its original purpose. Moody greatly influenced the cause of cross-cultural Christian missions after he met Hudson Taylor, a pioneer missionary to China. He actively supported the China Inland Mission and encouraged many of his congregation to volunteer for service overseas. International acclaim His influence was felt among Swedes. Being of English heritage, never visiting Sweden or any other Scandinavian country, and never speaking a word of Swedish, nonetheless, he became a hero revivalist among Swedish Mission Friends in Sweden and America. News of Moody's large revival campaigns in Great Britain from 1873 through 1875 traveled quickly to Sweden, making "Mr. Moody" a household name in homes of many Mission Friends. Moody's sermons published in Sweden were distributed in books, newspapers, and colporteur tracts, and they led to the spread of Sweden's "Moody fever" from 1875 through 1880. He preached his last sermon on November 16, 1899, in Kansas City, Missouri. Becoming ill, he returned home by train to Northfield. During the preceding several months, friends had observed he had added some to his already ample frame. Although his illness was never diagnosed, it has been speculated that he suffered from congestive heart failure. He died on December 26, 1899, surrounded by his family. Already installed as the leader of his Chicago Bible Institute, R. A. Torrey succeeded Moody as its pastor. Works Heaven Diggory Press Prevailing Prayer—What Hinders it? Diggory Press Secret Power Diggory Press The Ten Commandments Also, A Life for Christ—What a Normal Christian Life Looks Like. Legacy Religious historian James Findlay says that: Speaking before thousands in the dark business suit, bearded, rotund Dwight L. Moody seemed the epitome of the "businessman in clerical garb" who typified popular religion in late 19th-century America... Earthy, unlettered, a dynamo of energy, the revivalist was very much a man of his times... Moody adapted revivalism, one of the major institutions of evangelical Protestantism, to the urban context. ... His organizational ability, demonstrated in the great revivals he conducted in England, combined to fashion his spectacular career as the creator of modern mass revivalism. Ten years after Moody's death the Chicago Avenue Church was renamed the Moody Church in his honor, and the Chicago Bible Institute has likewise renamed the Moody Bible Institute. During World War II the Liberty ship was built in Panama City, Florida, and named in his honor. See also Horatio Spafford, a friend of Moody who wrote the words to the hymn It Is Well With My Soul Northfield Mount Hermon School References Sources "Dwight Moody: evangelist with a common touch" Christianity Today, 8 August 2008. Christian Biography Resources Dorsett, L. W. A Passion for Souls: The Life of D. L. Moody. 1997 Findlay, J. F. Jr. Dwight L. Moody: American Evangelist 1837–1899. 1969 Gundry, S. N. Love them in: The Proclamation Theology of D. L. Moody. 1976 Evensen, B. J. God's Man for Gilded Age: D. L. Moody and the Rise of Mass Evangelism. 2003 Gloege, Timothy. Guaranteed Pure: The Moody Bible Institute, Business, and the Making of Modern Evangelicalism (2017) Gustafson,	Keswickianism, who founded the Moody Church, Northfield School and Mount Hermon School in Massachusetts (now Northfield Mount Hermon School), Moody Bible Institute and Moody Publishers. One of his most famous quotes was "Faith makes all things possible... Love makes all things easy." Moody gave up his lucrative boot and shoe business to devote his life to revivalism, working first in the Civil War with Union troops through YMCA in the United States Christian Commission. In Chicago, he built one of the major evangelical centers in the nation, which is still active. Working with singer Ira Sankey, he toured the country and the British Isles, drawing large crowds with a dynamic speaking style. Early life Dwight Moody was born in Northfield, Massachusetts, as the seventh child in a large family. His father, Edwin J. Moody (1800–1841), was a small farmer and stonemason. His mother was Betsey Moody (née Holton; 1805–1896). They had five sons and a daughter before Dwight's birth. His father died when Dwight was age four; fraternal twins, a boy, and a girl were born one month after the father's death. Their mother struggled to support the nine children but had to send some off to work for their room and board. Dwight too was sent off, where he received cornmeal, porridge, and milk three times a day. He complained to his mother, but when she learned that he was getting all he wanted to eat, she sent him back. During this time, she continued to send the children to church. Together with his eight siblings, Dwight was raised in the Unitarian church. His oldest brother ran away and was not heard from by the family until many years later. When Moody turned 17, he moved to Boston to work (after receiving many job rejections locally) in an uncle's shoe store. One of the uncle's requirements was that Moody attend the Congregational Church of Mount Vernon, where Dr. Edward Norris Kirk served as the pastor. In April 1855 Moody was converted to evangelical Christianity when his Sunday school teacher, Edward Kimball, talked to him about how much God loved him. His conversion sparked the start of his career as an evangelist. Moody was not received by the church when he first applied in May 1855. He was not received as a church member until May 4, 1856. According to Moody's memoir, his teacher, Edward Kimball, said: Civil War D. L. Moody "could not conscientiously enlist" in the Union Army during the Civil War, later describing himself as "a Quaker" in this respect. After the Civil War started, he became involved with the United States Christian Commission of YMCA. He paid nine visits to the battlefront, being present among the Union soldiers after the Battle of Shiloh (a.k.a. Pittsburg Landing) and the Battle of Stones River; he also entered Richmond, Virginia, with the troops of General Grant. On August 28, 1862, Moody married Emma C. Revell, with whom he had daughter, Emma Reynolds Moody, and two sons,
than diets that maintain a typical mix of foods with smaller portions and perhaps some substitutions (e.g. low-fat milk, or less salad dressing). A meta-analysis of six randomized controlled trials found no difference between low-calorie, low-carbohydrate, and low-fat diets, with a 2–4 kilogram weight loss over 12–18 months in all studies. Diets that severely restrict calorie intake do not lead to long term weight loss. Extreme diets may, in some cases, lead to malnutrition. A major challenge regarding weight loss and dieting relates to compliance. While dieting can effectively promote weight loss in the short term, the intervention is hard to maintain over time and suppresses skeletal muscle thermogenesis. Suppressed thermogenesis accelerates weight regain once the diet stops, unless that phase is accompanied by a well-timed exercise intervention, as described by the Summermatter cycle. Some studies have found that, on average, short-term dieting results in a "meaningful" long-term weight-loss, although limited because of gradual 1 to 2 kg/year weight regain. Others have suggested that dieting is ineffective as a long-term intervention. For each individual, the results will be different, with some even regaining more weight than they lost, while a few others achieve a tremendous loss, so that the "average weight loss" of a diet is not indicative of the results other dieters may achieve. A 2001 meta-analysis of 29 American studies found that participants of structured weight-loss programs maintained an average of 23% (3 kg) of their initial weight loss after five years, representing an sustained 3.2% reduction in body mass. Unfortunately, patients are generally unhappy with weight loss of <10%, and reductions even as high as 10% are insufficient for changing someone with a "obese" BMI to a "normal weight" BMI. Long term losses from dieting are best maintained with continuing professional support, long term increases in physical activity, the use of anti-obesity medications, continued use of meal replacements, and additional periods of dieting to undo weight regain. The most effective approach to weight loss is an in-person, high-intensity, comprehensive lifestyle intervention: overweight or obese adults should maintain regular (at least monthly) contact with a trained interventionalist who can help them engage in exercise, monitor their body weight, and reduce their calorie consumption. For patients at high medical risk, bariatric surgery or medications may be warranted in addition to the lifestyle intervention, as dieting by itself may not lead to sustained weight loss. Many studies overestimate the benefits of calorie restriction because the studies confound exercise and diet (testing the effects of diet and exercise as a combined intervention, rather than the effects of diet alone). Adverse Effects Increased Mortality Rate A number of studies have found that intentional weight loss is associated with an increase in mortality in people without weight-related health problems. A 2009 meta-analysis of 26 studies found that "intentional weight loss had a small benefit for individuals classified as unhealthy (with obesity-related risk factors), especially unhealthy obese, but appeared to be associated with slightly increased mortality for healthy individuals, and for those who were overweight but not obese." Dietary Supplements Due to extreme or unbalanced diets, dietary supplements are sometimes taken in an attempt to replace missing vitamins or minerals. While some supplements could be helpful for people eating an unbalanced diet (if replacing essential nutrients, for example), overdosing on any dietary supplement can cause a range of side effects depending on the supplement and dose that is taken. Supplements should not replace foods that are important to a healthy diet. Eating disorders In an editorial for Psychological Medicine, George Hsu concludes that dieting is likely to lead to the development of an eating disorder in the presence of certain risk factors. A 2006 study found that dieting and unhealthy weight-control behaviors were predictive of obesity and eating disorders five years later, with the authors recommending a "shift away from dieting and drastic weight-control measures toward the long-term implementation of healthful eating and physical activity". Mechanism When the body is expending more energy than it is consuming (e.g. when exercising), the body's cells rely on internally stored energy sources, such as complex carbohydrates and fats, for energy. The first source to which the body turns is glycogen (by glycogenolysis). Glycogen is a complex carbohydrate, 65% of which is stored in skeletal muscles and the remainder in the liver (totaling about 2,000 kcal in the whole body). It is created from the excess of ingested macronutrients, mainly carbohydrates. When glycogen is nearly depleted, the body begins lipolysis, the mobilization and catabolism of fat stores for energy. In this process fats, obtained from adipose tissue, or fat cells, are broken down into glycerol	multiplied by the amount of carbohydrate. A meta-analysis by the Cochrane Collaboration concluded that low glycemic index or low glycemic load diets led to more weight loss and better lipid profiles but did not separate the effects of the load versus the index. Low-calorie Low-calorie diets usually produce an energy deficit of 500–1,000 calories per day, which can result in a weight loss per week. One of the most commonly used low-calorie diets is Weight Watchers. The National Institutes of Health reviewed 34 randomized controlled trials to determine the effectiveness of low-calorie diets. They found that these diets lowered total body mass by 8% in the short term, over 3–12 months. Women doing low-calorie diets should have at least 1,000 calories per day and men should have approximately 1,200 calories per day. These caloric intake values vary depending on additional factors, such as age and weight. Very low-calorie Very low calorie diets provide 200–800 calories per day, maintaining protein intake but limiting calories from both fat and carbohydrates. They subject the body to starvation and produce an average loss of per week. "2-4-6-8", a popular diet of this variety, follows a four-day cycle in which only 200 calories are consumed the first day, 400 the second day, 600 the third day, 800 the fourth day, and then totally fasting, after which the cycle repeats. There is some evidence that these diets results in considerable weight loss. These diets are not recommended for general use and should be reserved for the management of obesity as they are associated with adverse side effects such as loss of lean muscle mass, increased risks of gout, and electrolyte imbalances. People attempting these diets must be monitored closely by a physician to prevent complications. The concept of crash dieting is to drastically reduce calories, using a very-low-calorie diet. Crash dieting can be highly dangerous because it can cause various kind of issues for the human body. Crash dieting can produce weight loss but without professional supervision all along, the extreme reduction in calories and potential unbalance in the diet's composition can lead to detrimental effects, including sudden death. Fasting Fasting is when there is a long time interval between the meals. Lengthy fasting can also be dangerous due to the risk of malnutrition and should be carried out only under medical supervision. During prolonged fasting or very low calorie diets the reduction of blood glucose, the preferred energy source of the brain, causes the body to deplete its glycogen stores. Once glycogen is depleted the body begins to fuel the brain using ketones, while also metabolizing body protein (including but not limited to skeletal muscle) to be used to synthesize sugars for use as energy by the rest of the body. Most experts believe that a prolonged fast can lead to muscle wasting, although some dispute this. The use of short-term fasting, or various forms of intermittent fasting, have been used as a form of dieting to circumvent the issues of long fasting. Detox Detox diets are promoted with unsubstantiated claims that they can eliminate "toxins" from the human body. Many of these diets use herbs or celery and other juicy low-calorie vegetables. Environmentally sustainable Another kind of diet focuses not on the dieter's health effects, but on its environment. The One Blue Dot plan of the BDA offers recommendations towards reducing diets' environmental impacts, by: Reducing meat to 70g per person per day. Prioritising plant proteins. Promoting fish from sustainable sources. Moderate dairy consumption. Focusing on wholegrain starchy foods. Promoting seasonal locally sourced fruits and vegetables. Reducing high fat, sugar and salty foods overconsumption. Promoting tap water and unsweetened tea/coffee as the de facto choice for healthy hydration. Reducing food waste. Effectiveness Several diets are effective for weight loss of obese individuals, with diet success most predicted by adherence and little effect resulting from the type or brand of diet. As weight maintenance depends on calorie intake, diets emphasising certain macronutrients (low-fat, low-carbohydrate, etc.) have been shown to be no more effective than one another and no more effective than diets that maintain a typical mix of foods with smaller portions and perhaps some substitutions (e.g. low-fat milk, or less salad dressing). A meta-analysis of six randomized controlled trials found no difference between low-calorie,
(Holy Roman Empire), the imperial assembly of the princes of the Holy Roman Empire until 1806 Reichstag Reichstag (German Empire) (Reichstag), the Diet of the Empire, the legislative assembly of the German Empire, 1871–1917 Reichstag (Weimar Republic), (Reichstag), the Diet of the Weimar Republic, from 1919 to 1933 Reichstag (Nazi Germany), (Reichstag), the Diet of Nazi Germany, from 1933 to 1945, a purely ceremonial "parliament" in a totalitarian dictatorship without elections Television, film, or music "Diet", an episode of the Adult Swim animated television series, Aqua Teen Hunger Force The Diet (cartoon), a Beetle Bailey animated short "Diet", a 2020 single by Peakboy Other uses DIET, an open-source middleware for high-performance computing District Institute of Education and Training, in India DIET, direct electron transfer involving bacterial nanowires in species such as Geobacter See also Diets, a historical name for the Dutch language in general Dietsch (disambiguation), distinguishes the southern dialects in the	intake Diet food, foods that aid in creating a diet for weight loss or gain Healthy diet, the process of helping to maintain or improve overall health Politics Diet (assembly), a formal deliberative assembly Current National Diet, Japan's bicameral legislature, in its current form since 1947, composed of the House of Representatives and the House of Councillors Landtag, a diet of states and provinces in Germany, Austria, South Tyrol in Italy, and the national parliament of Liechtenstein Bundestag (Deutscher Bundestag), the lower house of Germany's Parliament, established in West
in May 1970. They claimed that they had synthesized more nuclei of element 105 and that the experiment confirmed their previous work. According to the paper, the isotope produced by JINR was probably 261105, or possibly 260105. This report included an initial chemical examination: the thermal gradient version of the gas-chromatography method was applied to demonstrate that the chloride of what had formed from the SF activity nearly matched that of niobium pentachloride, rather than hafnium tetrachloride. The team identified a 2.2-second SF activity in a volatile chloride portraying eka-tantalum properties, and inferred that the source of the SF activity must have been element 105. In June 1970, JINR made improvements on their first experiment, using a purer target and reducing the intensity of transfer reactions by installing a collimator before the catcher. This time, they were able to find 9.1 MeV alpha activities with daughter isotopes identifiable as either 256103 or 257103, implying that the original isotope was either 260105 or 261105. Naming controversy JINR did not propose a name after their first report claiming synthesis of element 105, which would have been the usual practice. This led LBL to believe that JINR did not have enough experimental data to back their claim. After collecting more data, JINR proposed the name nielsbohrium (Ns) in honor of the Danish nuclear physicist Niels Bohr, a founder of the theories of atomic structure and quantum theory. When LBL first announced their synthesis of element 105, they proposed that the new element be named hahnium (Ha) after the German chemist Otto Hahn, the "father of nuclear chemistry", thus creating an element naming controversy. In the early 1970s, both teams reported synthesis of the next element, element 106, but did not suggest names. JINR suggested establishing an international committee to clarify the discovery criteria. This proposal was accepted in 1974 and a neutral joint group formed. Neither team showed interest in resolving the conflict through a third party, so the leading scientists of LBL—Albert Ghiorso and Glenn Seaborg—traveled to Dubna in 1975 and met with the leading scientists of JINR—Georgy Flerov, Yuri Oganessian, and others— to try to resolve the conflict internally and render the neutral joint group unnecessary; after two hours of discussions, this failed. The joint neutral group never assembled to assess the claims and the conflict remained unsolved. In 1979, IUPAC suggested systematic element names to be used as placeholders until permanent names were established; under it, element 105 would be unnilpentium, from the Latin roots un- and nil- and the Greek root pent- (meaning "one", "zero", and "five", respectively, the digits of the atomic number). Both teams ignored it as they did not wish to weaken their outstanding claims. In 1981, the Gesellschaft für Schwerionenforschung (GSI; Society for Heavy Ion Research) in Darmstadt, Hesse, West Germany, claimed synthesis of element 107; their report came out five years after the first report from JINR but with greater precision, making a more solid claim on discovery. GSI acknowledged JINR's efforts by suggesting the name nielsbohrium for the new element. JINR did not suggest a new name for element 105, stating it was more important to determine its discoverers first. In 1985, the International Union of Pure and Applied Chemistry (IUPAC) and the International Union of Pure and Applied Physics (IUPAP) formed a Transfermium Working Group (TWG) to assess discoveries and establish final names for the controversial elements. The party held meetings with delegates from the three competing institutes; in 1990, they established criteria on recognition of an element, and in 1991, they finished the work on assessing discoveries and disbanded. These results were published in 1993. According to the report, the first definitely successful experiment was the April 1970 LBL experiment, closely followed by the June 1970 JINR experiment, so credit for the discovery of the element should be shared between the two teams. LBL said that the input from JINR was overrated in the review. They claimed JINR was only able to unambiguously demonstrate the synthesis of element 105 a year after they did. JINR and GSI endorsed the report. In 1994, IUPAC published a recommendation on naming the disputed elements. For element 105, they proposed joliotium (Jl) after the French physicist Frédéric Joliot-Curie, a contributor to the development of nuclear physics and chemistry; this name was originally proposed by the Soviet team for element 102, which by then had long been called nobelium. This recommendation was criticized by the American scientists for several reasons. Firstly, their suggestions were scrambled: the names rutherfordium and hahnium, originally suggested by Berkeley for elements 104 and 105, were respectively reassigned to elements 106 and 108. Secondly, elements 104 and 105 were given names favored by JINR, despite earlier recognition of LBL as an equal co-discoverer for both of them. Thirdly and most importantly, IUPAC rejected the name seaborgium for element 106, having just approved a rule that an element could not be named after a living person, even though the 1993 report had given the LBL team the sole credit for its discovery. In 1995, IUPAC abandoned the controversial rule and established a committee of national representatives aimed at finding a compromise. They suggested seaborgium for element 106 in exchange for the removal of all the other American proposals, except for the established name lawrencium for element 103. The equally entrenched name nobelium for element 102 was replaced by flerovium after Georgy Flerov, following the recognition by the 1993 report that that element had been first synthesized in Dubna. This was rejected by American scientists and the decision was retracted. The name flerovium was later used for element 114. In 1996, IUPAC held another meeting, reconsidered all names in hand, and accepted another set of recommendations; it was approved and published in 1997. Element 105 was named dubnium (Db), after Dubna in Russia, the location of the JINR; the American suggestions were used for elements 102, 103, 104, and 106. The name dubnium had been used for element 104 in the previous IUPAC recommendation. The American scientists "reluctantly" approved this decision. IUPAC pointed out that the Berkeley laboratory had already been recognized several times, in the naming of berkelium, californium, and americium, and that the acceptance of the names rutherfordium and seaborgium for elements 104 and 106 should be offset by recognizing JINR's contributions to the discovery of elements 104, 105, and 106. Isotopes Dubnium, having an atomic number of 105, is a superheavy element; like all elements with such high atomic numbers, it is very unstable. The longest-lasting known isotope of dubnium, 268Db, has a half-life of around a day. No stable isotopes have been seen, and a 2012 calculation by JINR suggested that the half-lives of all dubnium isotopes would not significantly exceed a day. Dubnium can only be obtained by artificial production. The short half-life of dubnium limits experimentation. This is exacerbated by the fact that the most stable isotopes are the hardest to synthesize. Elements with a lower atomic number have stable isotopes with a lower neutron–proton ratio than those with higher atomic number, meaning that the target and beam nuclei that could be employed to create the superheavy element have fewer neutrons than needed to form these most stable isotopes. (Different techniques based on rapid neutron capture and transfer reactions are being considered as of the 2010s, but those based on the collision of a large and small nucleus still dominate research in the area.) Only a few atoms of 268Db can be produced in each experiment, and thus the measured lifetimes vary significantly during the process. During three experiments, 23 atoms were created in total, with a resulting half-life of . The second most stable isotope, 270Db, has been produced in even smaller quantities: three atoms in total, with lifetimes of 33.4 h, 1.3 h, and 1.6 h. These two are the heaviest isotopes of dubnium to date, and both were produced as a result of decay of the heavier nuclei 288Mc and 294Ts rather than directly, because the experiments that yielded them were originally designed in Dubna for 48Ca beams. For its mass, 48Ca has by far the greatest neutron excess of all practically stable nuclei, both quantitative and relative, which correspondingly helps synthesize superheavy nuclei with more neutrons, but this gain is compensated by the decreased likelihood of fusion for high atomic numbers. Predicted properties According to the periodic law, dubnium should belong to group 5, with vanadium, niobium, and tantalum. Several studies have investigated the properties of element 105 and found that they generally agreed with the predictions of the periodic law. Significant deviations may nevertheless occur, due to relativistic effects, which dramatically change physical properties on both atomic and macroscopic scales. These properties have remained challenging to measure for several reasons: the difficulties of production of superheavy atoms, the low rates of production, which only allows for microscopic scales, requirements for a radiochemistry laboratory to test the atoms, short half-lives of those atoms, and the presence of many unwanted activities apart from those of synthesis of superheavy atoms. So far, studies have only been performed on single atoms. Atomic and physical A direct relativistic effect is that as the atomic numbers of elements increase, the innermost electrons begin to revolve faster around the nucleus as a result of an increase of electromagnetic attraction between an electron and a nucleus. Similar effects have been found for the outermost s orbitals (and p1/2 ones, though in dubnium they are not occupied): for example, the 7s orbital contracts by 25% in size and is stabilized by 2.6 eV. A more indirect effect is that the contracted s and p1/2 orbitals shield the charge of the nucleus more effectively, leaving less for the outer d and f electrons, which therefore move in larger orbitals. Dubnium is greatly affected by this: unlike the previous group 5 members, its 7s electrons are slightly more difficult to extract than its 6d electrons. Another effect is the spin–orbit interaction, particularly spin–orbit splitting, which splits the 6d subshell—the azimuthal quantum number ℓ of a d shell is 2—into two subshells, with four of the ten orbitals having their ℓ lowered to 3/2 and six raised to 5/2. All ten energy levels are raised; four of them are lower than the other six. (The three 6d electrons normally occupy the lowest energy levels, 6d3/2.) A singly ionized atom of dubnium (Db+) should lose a 6d electron compared to a neutral atom; the doubly (Db2+) or triply (Db3+) ionized atoms of dubnium should eliminate 7s electrons, unlike its lighter homologs. Despite the changes, dubnium is still expected to have five valence electrons; 7p energy levels have not been shown to influence dubnium and its properties. As the 6d orbitals of dubnium are more destabilized than the 5d ones of tantalum, and Db3+ is expected to have two 6d, rather than 7s, electrons remaining, the resulting +3 oxidation state is expected to be unstable and even rarer than that of tantalum. The ionization potential of dubnium in its maximum +5 oxidation state should be slightly lower than that of tantalum and the ionic radius of dubnium	in 1993 by an official investigation of the discovery claims by the Transfermium Working Group, formed by the International Union of Pure and Applied Chemistry and the International Union of Pure and Applied Physics, resulting in credit for the discovery being officially shared between both teams. The element was formally named dubnium in 1997 after the town of Dubna, the site of the JINR. Theoretical research establishes dubnium as a member of group 5 in the 6d series of transition metals, placing it under vanadium, niobium, and tantalum. Dubnium should share most properties, such as its valence electron configuration and having a dominant +5 oxidation state, with the other group 5 elements, with a few anomalies due to relativistic effects. A limited investigation of dubnium chemistry has confirmed this. Solution chemistry experiments have revealed that dubnium often behaves more like niobium rather than tantalum, breaking periodic trends. Introduction Discovery Background Uranium, element 92, is the heaviest element to occur in significant quantities in nature; heavier elements can only be practically produced by synthesis. The first synthesis of a new element—neptunium, element 93—was achieved in 1940 by a team of researchers in the United States. In the following years, American scientists synthesized the elements up to mendelevium, element 101, which was synthesized in 1955. From element 102, the priority of discoveries was contested between American and Soviet physicists. Their rivalry resulted in a race for new elements and credit for their discoveries, later named the Transfermium Wars. Reports The first report of the discovery of element 105 came from the Joint Institute for Nuclear Research (JINR) in Dubna, Moscow Oblast, Soviet Union, in April 1968. The scientists bombarded 243Am with a beam of 22Ne ions, and reported 9.4 MeV (with a half-life of 0.1–3 seconds) and 9.7 MeV (t1/2 > 0.05 s) alpha activities followed by alpha activities similar to those of either 256103 or 257103. Based on prior theoretical predictions, the two activity lines were assigned to 261105 and 260105, respectively. + → 265−x105 + x (x = 4, 5) After observing the alpha decays of element 105, the researchers aimed to observe spontaneous fission (SF) of the element and study the resulting fission fragments. They published a paper in February 1970, reporting multiple examples of two such activities, with half-lives of 14 ms and . They assigned the former activity to 242mfAm and ascribed the latter activity to an isotope of element 105. They suggested that it was unlikely that this activity could come from a transfer reaction instead of element 105, because the yield ratio for this reaction was significantly lower than that of the 242mfAm-producing transfer reaction, in accordance with theoretical predictions. To establish that this activity was not from a (22Ne,xn) reaction, the researchers bombarded a 243Am target with 18O ions; reactions producing 256103 and 257103 showed very little SF activity (matching the established data), and the reaction producing heavier 258103 and 259103 produced no SF activity at all, in line with theoretical data. The researchers concluded that the activities observed came from SF of element 105. In April 1970, a team at Lawrence Berkeley Laboratory (LBL), in Berkeley, California, United States, claimed to have synthesized element 105 by bombarding californium-249 with nitrogen-15 ions, with an alpha activity of 9.1 MeV. To ensure this activity was not from a different reaction, the team attempted other reactions: bombarding 249Cf with 14N, Pb with 15N, and Hg with 15N. They stated no such activity was found in those reactions. The characteristics of the daughter nuclei matched those of 256103, implying that the parent nuclei were of 260105. + → 260105 + 4 These results did not confirm the JINR findings regarding the 9.4 MeV or 9.7 MeV alpha decay of 260105, leaving only 261105 as a possibly produced isotope. JINR then attempted another experiment to create element 105, published in a report in May 1970. They claimed that they had synthesized more nuclei of element 105 and that the experiment confirmed their previous work. According to the paper, the isotope produced by JINR was probably 261105, or possibly 260105. This report included an initial chemical examination: the thermal gradient version of the gas-chromatography method was applied to demonstrate that the chloride of what had formed from the SF activity nearly matched that of niobium pentachloride, rather than hafnium tetrachloride. The team identified a 2.2-second SF activity in a volatile chloride portraying eka-tantalum properties, and inferred that the source of the SF activity must have been element 105. In June 1970, JINR made improvements on their first experiment, using a purer target and reducing the intensity of transfer reactions by installing a collimator before the catcher. This time, they were able to find 9.1 MeV alpha activities with daughter isotopes identifiable as either 256103 or 257103, implying that the original isotope was either 260105 or 261105. Naming controversy JINR did not propose a name after their first report claiming synthesis of element 105, which would have been the usual practice. This led LBL to believe that JINR did not have enough experimental data to back their claim. After collecting more data, JINR proposed the name nielsbohrium (Ns) in honor of the Danish nuclear physicist Niels Bohr, a founder of the theories of atomic structure and quantum theory. When LBL first announced their synthesis of element 105, they proposed that the new element be named hahnium (Ha) after the German chemist Otto Hahn, the "father of nuclear chemistry", thus creating an element naming controversy. In the early 1970s, both teams reported synthesis of the next element, element 106, but did not suggest names. JINR suggested establishing an international committee to clarify the discovery criteria. This proposal was accepted in 1974 and a neutral joint group formed. Neither team showed interest in resolving the conflict through a third party, so the leading scientists of LBL—Albert Ghiorso and Glenn Seaborg—traveled to Dubna in 1975 and met with the leading scientists of JINR—Georgy Flerov, Yuri Oganessian, and others— to try to resolve the conflict internally and render the neutral joint group unnecessary; after two hours of discussions, this failed. The joint neutral group never assembled to assess the claims and the conflict remained unsolved. In 1979, IUPAC suggested systematic element names to be used as placeholders until permanent names were established; under it, element 105 would be unnilpentium, from the Latin roots un- and nil- and the Greek root pent- (meaning "one", "zero", and "five", respectively, the digits of the atomic number). Both teams ignored it as they did not wish to weaken their outstanding claims. In 1981, the Gesellschaft für Schwerionenforschung (GSI; Society for Heavy Ion Research) in Darmstadt, Hesse, West Germany, claimed synthesis of element 107; their report came out five years after the first report from JINR but with greater precision, making a more solid claim on discovery. GSI acknowledged JINR's efforts by suggesting the name nielsbohrium for the new element. JINR did not suggest a new name for element 105, stating it was more important to determine its discoverers first. In 1985, the International Union of Pure and Applied Chemistry (IUPAC) and the International Union of Pure and Applied Physics (IUPAP) formed a Transfermium Working Group (TWG) to assess discoveries and establish final names for the controversial elements. The party held meetings with delegates from the three competing institutes; in 1990, they established criteria on recognition of an element, and in 1991, they finished the work on assessing discoveries and disbanded. These results were published in 1993. According to the report, the first definitely successful experiment was the April 1970 LBL experiment, closely followed by the June 1970 JINR experiment, so credit for the discovery of the element should be shared between the two teams. LBL said that the input from JINR was overrated in the review. They claimed JINR was only able to unambiguously demonstrate the synthesis of element 105 a year after they did. JINR and GSI endorsed the report. In 1994, IUPAC published a recommendation on naming the disputed elements. For element 105, they proposed joliotium (Jl) after the French physicist Frédéric Joliot-Curie, a contributor to the development of nuclear physics and chemistry; this name was originally proposed by the Soviet team for element 102, which by then had long been called nobelium. This recommendation was criticized by the American scientists for several reasons. Firstly, their suggestions were scrambled: the names rutherfordium and hahnium, originally suggested by Berkeley for elements 104 and 105, were respectively reassigned to elements 106 and 108. Secondly, elements 104 and 105 were given names favored by JINR, despite earlier recognition of LBL as an equal co-discoverer for both of them. Thirdly and most importantly, IUPAC rejected the name seaborgium for element 106, having just approved a rule that an element could not be named after a living person, even though the 1993 report had given the LBL team the sole credit for its discovery. In 1995, IUPAC abandoned the controversial rule and established a committee of national representatives aimed at finding a compromise. They suggested seaborgium for element 106 in exchange for the removal of all the other American proposals, except for the established name lawrencium for element 103. The equally entrenched name nobelium for element 102 was replaced by flerovium after Georgy Flerov, following the recognition by the 1993 report that that element had been first synthesized in Dubna. This was rejected by American scientists and the decision was retracted. The name flerovium was later used for element 114. In 1996, IUPAC held another meeting, reconsidered all names in hand, and accepted another set of recommendations; it was approved and published in 1997. Element 105 was named dubnium (Db), after Dubna in Russia, the location of the JINR; the American suggestions were used for elements 102, 103, 104, and 106. The name dubnium had been used for element 104 in the previous IUPAC recommendation. The American scientists "reluctantly" approved this decision. IUPAC pointed out that the Berkeley laboratory had already been recognized several times, in the naming of berkelium, californium, and americium, and that the acceptance of the names rutherfordium and seaborgium for elements 104 and 106 should be offset by recognizing JINR's contributions to the discovery of elements 104, 105, and 106. Isotopes Dubnium, having an atomic number of 105, is a superheavy element; like all elements with such high atomic numbers, it is very unstable. The longest-lasting known isotope of dubnium, 268Db, has a half-life of around a day. No stable isotopes have been seen, and a 2012 calculation by JINR suggested that the half-lives of all dubnium isotopes would not significantly exceed a day. Dubnium can only be obtained by artificial production. The short half-life of dubnium limits experimentation. This is exacerbated by the fact that the most stable isotopes are the hardest to synthesize. Elements with a lower atomic number have stable isotopes with a lower neutron–proton ratio than
agent. Sucrose and trehalose are examples of non-reducing disaccharides because their glycosidic bond is between their respective hemiacetal carbon atoms. The reduced chemical reactivity of the non-reducing sugars in comparison to reducing sugars, may be an advantage where stability in storage is important. Formation The formation of a disaccharide molecule from two monosaccharide molecules proceeds by displacing a hydroxy group from one molecule and a hydrogen nucleus (a proton) from the other, so that the now vacant bonds on the monosaccharides join the two monomers together. Because of the removal of the water molecule from the product, the term of convenience for such a process is "dehydration reaction" (also "condensation reaction" or "dehydration synthesis"). For example, milk sugar (lactose) is a disaccharide made by condensation of one molecule of each of the monosaccharides glucose and galactose, whereas the disaccharide sucrose in sugar cane and sugar beet, is a condensation product of glucose and fructose. Maltose, another common disaccharide, is condensed from two glucose molecules. The dehydration reaction that bonds monosaccharides into disaccharides (and also bonds monosaccharides into more complex polysaccharides) forms what are called glycosidic bonds. Properties The glycosidic bond can be formed between any hydroxy group on the component monosaccharide. So, even if both component sugars are the same (e.g., glucose), different bond combinations (regiochemistry) and stereochemistry (alpha- or beta-) result in disaccharides that are diastereoisomers with different chemical and physical properties. Depending on the monosaccharide constituents, disaccharides are sometimes crystalline, sometimes water-soluble, and sometimes sweet-tasting and sticky-feeling. Disaccharides can serve as functional groups by forming glycosidic bonds with other organic compounds, forming biosides. Assimilation Digestion involves breakdown to the monosaccharides. Common disaccharides {\| class="wikitable" \|- ! Disaccharide !! Unit 1 !! Unit 2 !! Bond \|- \| Sucrose (table sugar, cane sugar, beet sugar, or saccharose) \| Glucose \|\| Fructose \|\| α(1→2)β \|- \| Lactose (milk sugar) \|\| Galactose \|\| Glucose \|\| β(1→4) \|- \| Maltose (malt sugar) \|\| Glucose \|\| Glucose \|\| α(1→4) \|- \| Trehalose \|\| Glucose \|\| Glucose \|\| α(1→1)α \|- \| Cellobiose \|\| Glucose \|\| Glucose \|\| β(1→4) \|- \| Chitobiose \|\| Glucosamine \|\| Glucosamine \|\| β(1→4) \|} Maltose, cellobiose, and chitobiose are hydrolysis products of the polysaccharides starch, cellulose, and chitin, respectively. Less common disaccharides include: {\| class="wikitable" \|- ! Disaccharide !! Units !! Bond \|- \| Kojibiose \|\| two glucose monomers \|\| α(1→2) \|- \| Nigerose \|\| two glucose monomers \|\| α(1→3) \|- \| Isomaltose \|\| two glucose monomers \|\| α(1→6) \|- \| β,β-Trehalose \|\| two glucose monomers \|\| β(1→1)β \|- \| α,β-Trehalose \|\| two glucose monomers \|\| α(1→1)β \|- \|	component monosaccharides bond through an acetal linkage between their anomeric centers. This results in neither monosaccharide being left with a hemiacetal unit that is free to act as a reducing agent. Sucrose and trehalose are examples of non-reducing disaccharides because their glycosidic bond is between their respective hemiacetal carbon atoms. The reduced chemical reactivity of the non-reducing sugars in comparison to reducing sugars, may be an advantage where stability in storage is important. Formation The formation of a disaccharide molecule from two monosaccharide molecules proceeds by displacing a hydroxy group from one molecule and a hydrogen nucleus (a proton) from the other, so that the now vacant bonds on the monosaccharides join the two monomers together. Because of the removal of the water molecule from the product, the term of convenience for such a process is "dehydration reaction" (also "condensation reaction" or "dehydration synthesis"). For example, milk sugar (lactose) is a disaccharide made by condensation of one molecule of each of the monosaccharides glucose and galactose, whereas the disaccharide sucrose in sugar cane and sugar beet, is a condensation product of glucose and fructose. Maltose, another common disaccharide, is condensed from two glucose molecules. The dehydration reaction that bonds monosaccharides into disaccharides (and also bonds monosaccharides into more complex polysaccharides) forms what are called glycosidic bonds. Properties The glycosidic bond can be formed between any hydroxy group on the component monosaccharide. So, even if both component sugars are the same (e.g., glucose), different bond combinations (regiochemistry) and stereochemistry (alpha- or beta-) result in disaccharides that are diastereoisomers with different chemical and physical properties. Depending on the monosaccharide constituents, disaccharides are sometimes crystalline, sometimes water-soluble, and sometimes sweet-tasting and sticky-feeling. Disaccharides can serve as functional groups by forming glycosidic bonds with other organic compounds, forming biosides. Assimilation Digestion involves breakdown to the monosaccharides. Common disaccharides
flowing narrative of epic. They are generally considered the most grandiose and formal meter. An English-language example of the dactylic hexameter, in quantitative meter: Down in a \| deep dark \| dell sat an \| old cow \| munching a \| beanstalk The preceding line follows the rules of Greek and Latin prosody. Syllables containing long vowels, diphthongs and short vowels followed by two or more consonants count as long; all other syllables count as short. Such values may not correspond with the rhythms of ordinary spoken English. In Greek The hexameter was first used by early Greek poets of the oral tradition, and the most complete extant examples of their works are the Iliad and the Odyssey, which influenced the authors of all later classical epics that survive today. Early epic poetry was also accompanied by music, and pitch changes associated with the accented Greek must have highlighted the melody, though the exact mechanism is still a topic of discussion. The Homeric poems arrange words so as to create an interplay between the metrical ictus—the first syllable of each foot—and the natural, spoken accent of words. If the ictus and accent coincide too frequently the hexameter becomes "sing-songy". Thus in general, word breaks occur in the middle of metrical feet, while ictus and accent coincide more often near the end of the line. The first line of Homer’s Iliad—"Sing, goddess, the anger of Peleus’ son Achilles"—provides an example: Dividing the line into metrical units: dactyl, dactyl, spondee, dactyl, dactyl, spondee. Note how the word endings do not coincide with the end of a metrical foot; for the early part of the line this forces the accent of each word to lie in the middle of a foot, playing against the ictus. This line also includes a masculine caesura after , a break that separates the line into two parts. Homer employs a feminine caesura more commonly than later writers: an example occurs in Iliad I.5 "...and every bird; thus the plan of Zeus came to fulfillment": Homer’s hexameters contain a higher proportion of dactyls than later hexameter poetry. They are also characterised by a laxer following of verse principles than later epicists almost invariably adhered to. For example, Homer allows spondaic fifth feet (albeit not often), whereas many later authors never do. Homer also altered the forms of words to allow them to fit the hexameter, typically by using a dialectal form: ptolis is an epic form used instead of the Attic polis as necessary for the meter. Proper names sometimes take forms to fit the meter, for example Pouludamas instead of the metrically unviable Poludamas. Some lines require a knowledge of the digamma for their scansion, e.g. Iliad I.108 "you have not yet spoken a good word nor brought one to pass": Here the word (epos) was originally (wepos) in Ionian; the digamma, later lost, lengthened the last syllable of the preceding (eipas) and removed the apparent defect in the meter. A digamma also saved the hiatus in the third foot. This example demonstrates the oral tradition of the Homeric epics that flourished before they were written down sometime in the 7th century BC. In spite of the occasional exceptions in early epic, most of the later rules of hexameter composition have their origins in the methods and practices of Homer. In Latin The hexameter came into Latin as an adaptation from Greek long after the practice of singing the epics had faded. Consequentially, the properties of the meter were learned as specific "rules" rather than as a natural result of musical expression. Also, because the Latin language generally has a higher proportion of long syllables than Greek, it is by nature more spondaic. Thus the Latin hexameter took on characteristics of its own. The earliest example of hexameter in Latin poetry is the Annales of Ennius, which established it as the standard for later Latin epics. Later Republican writers, such as Lucretius, Catullus and even Cicero, wrote hexameter compositions, and it was at this time that many of the principles of Latin hexameter were firmly established, and followed by later writers such as Virgil, Ovid, Lucan, and Juvenal. Virgil's opening line for the Aeneid is a classic example:: "I sing of arms and the man, who first from the shores of Troy..." As in Greek, lines were arranged so that the metrically long syllables—those occurring at the beginning of a foot—often avoided the natural stress of a word. In the earlier feet of a line, meter and stress were expected to clash, while in the later feet they were expected to resolve and coincide—an effect that gives each line a natural "dum-ditty-dum-dum" ("shave and a haircut") rhythm to close. Such an arrangement is a balance between an exaggerated emphasis on the metre—which would cause the verse to be sing-songy—and the need to provide some repeated rhythmic guide for skilled recitation. In the following example of Ennius's early Latin hexameter composition, metrical weight () falls on the first and last syllables of ; the ictus is therefore opposed to the natural stress on the second syllable when the word is pronounced. Similarly, the second syllable of the words and carry the metrical ictus even though the first is naturally stressed in typical pronunciation. In the closing feet of the line, the natural stress that falls on the third syllable of and the second syllable of coincide with the metrical ictus and produce the characteristic "shave and a haircut" ending: (Ennius, Annales 1.86) "they were disputing whether they should call the city 'Roma' or 'Remora'." Like their Greek predecessors, classical Latin poets avoided a large number of word breaks at the ends of foot divisions except between the fourth and fifth, where it was encouraged. In order to preserve the rhythmic close, Latin poets avoided the placement of a single syllable or four-syllable word at the end of a line. The caesura is also handled far more strictly, with Homer's feminine caesura becoming exceedingly rare, and the second-foot caesura always paired with one in the fourth. One example of the evolution of the Latin verse form can be seen in a comparative analysis of the use of spondees in Ennius' time vs. the Augustan age. The repeated use of the heavily spondaic line came to be frowned upon, as well as the use of a high proportion of spondees in both of the first two feet. The following lines of Ennius would not have been felt admissible by later authors since they both contain repeated spondees at the beginning of consecutive lines: (Annales 1.42f) "with these words: 'o daughter, tribulations must first be borne by you; later your fortune will rise again from the river.'" However, it is from Virgil that the following famous, heavily spondaic line (note the elision of hiatuses!) comes: (Aeneid III.658) "a huge, shapeless, horrendous monster, whose light [i.e., its eye] had been removed" Virgil and the Augustan poets By the age of Augustus, poets like Virgil closely followed the rules of the meter and approached it in a highly rhetorical way, looking for effects that can be exploited in skilled recitation. For example, the following line from the Aeneid (VIII.596) describes the movement of rushing horses and how "a hoof shakes the crumbling field with a galloping sound": This line is made up of five dactyls and a closing spondee, an unusual rhythmic arrangement that imitates the described action. A similar effect is found in VIII.452, where Virgil describes how the blacksmith sons of Vulcan "lift their arms with great strength one to another" in forging Aeneas' shield: The line consists of all spondees except for the usual dactyl in the fifth foot, and is meant to mimic the pounding sound of the work. A third example that mixes the two effects comes from I.42, where Juno pouts that Athena was allowed to	typically by using a dialectal form: ptolis is an epic form used instead of the Attic polis as necessary for the meter. Proper names sometimes take forms to fit the meter, for example Pouludamas instead of the metrically unviable Poludamas. Some lines require a knowledge of the digamma for their scansion, e.g. Iliad I.108 "you have not yet spoken a good word nor brought one to pass": Here the word (epos) was originally (wepos) in Ionian; the digamma, later lost, lengthened the last syllable of the preceding (eipas) and removed the apparent defect in the meter. A digamma also saved the hiatus in the third foot. This example demonstrates the oral tradition of the Homeric epics that flourished before they were written down sometime in the 7th century BC. In spite of the occasional exceptions in early epic, most of the later rules of hexameter composition have their origins in the methods and practices of Homer. In Latin The hexameter came into Latin as an adaptation from Greek long after the practice of singing the epics had faded. Consequentially, the properties of the meter were learned as specific "rules" rather than as a natural result of musical expression. Also, because the Latin language generally has a higher proportion of long syllables than Greek, it is by nature more spondaic. Thus the Latin hexameter took on characteristics of its own. The earliest example of hexameter in Latin poetry is the Annales of Ennius, which established it as the standard for later Latin epics. Later Republican writers, such as Lucretius, Catullus and even Cicero, wrote hexameter compositions, and it was at this time that many of the principles of Latin hexameter were firmly established, and followed by later writers such as Virgil, Ovid, Lucan, and Juvenal. Virgil's opening line for the Aeneid is a classic example:: "I sing of arms and the man, who first from the shores of Troy..." As in Greek, lines were arranged so that the metrically long syllables—those occurring at the beginning of a foot—often avoided the natural stress of a word. In the earlier feet of a line, meter and stress were expected to clash, while in the later feet they were expected to resolve and coincide—an effect that gives each line a natural "dum-ditty-dum-dum" ("shave and a haircut") rhythm to close. Such an arrangement is a balance between an exaggerated emphasis on the metre—which would cause the verse to be sing-songy—and the need to provide some repeated rhythmic guide for skilled recitation. In the following example of Ennius's early Latin hexameter composition, metrical weight () falls on the first and last syllables of ; the ictus is therefore opposed to the natural stress on the second syllable when the word is pronounced. Similarly, the second syllable of the words and carry the metrical ictus even though the first is naturally stressed in typical pronunciation. In the closing feet of the line, the natural stress that falls on the third syllable of and the second syllable of coincide with the metrical ictus and produce the characteristic "shave and a haircut" ending: (Ennius, Annales 1.86) "they were disputing whether they should call the city 'Roma' or 'Remora'." Like their Greek predecessors, classical Latin poets avoided a large number of word breaks at the ends of foot divisions except between the fourth and fifth, where it was encouraged. In order to preserve the rhythmic close, Latin poets avoided the placement of a single syllable or four-syllable word at the end of a line. The caesura is also handled far more strictly, with Homer's feminine caesura becoming exceedingly rare, and the second-foot caesura always paired with one in the fourth. One example of the evolution of the Latin verse form can be seen in a comparative analysis of the use of spondees in Ennius' time vs. the Augustan age. The repeated use of the heavily spondaic line came to be frowned upon, as well as the use of a high proportion of spondees in both of the first two feet. The following lines of Ennius would not have been felt admissible by later authors since they both contain repeated spondees at the beginning of consecutive lines: (Annales 1.42f) "with these words: 'o daughter, tribulations must first be borne by you; later your fortune will rise again from the river.'" However, it is from Virgil that the following famous, heavily spondaic line (note the elision of hiatuses!) comes: (Aeneid III.658) "a huge, shapeless, horrendous monster, whose light [i.e., its eye] had been removed" Virgil and the Augustan poets By the age of Augustus, poets like Virgil closely followed the rules of the meter and approached it in a highly rhetorical way, looking for effects that can be exploited in skilled recitation. For example, the following line from the Aeneid (VIII.596) describes the movement of rushing horses and how "a hoof shakes the crumbling field with a galloping sound": This line is made up of five dactyls and a closing spondee, an unusual rhythmic arrangement that imitates the described action. A similar effect is found in VIII.452, where Virgil describes how the blacksmith sons of Vulcan "lift their arms with great strength one to another" in forging Aeneas' shield: The line consists of all spondees except for the usual dactyl in the fifth foot, and is meant to mimic the pounding sound of the work. A third example that mixes the two effects comes from I.42, where Juno pouts that Athena was allowed to use Jove's thunderbolts to destroy Ajax ("she hurled Jove's quick fire from the clouds"): This line is nearly all dactyls except for the spondee at -lata e. This change in rhythm paired with the harsh elision is intended to emphasize the crash of Athena's thunderbolt. Virgil will occasionally deviate from the strict rules of the meter to produce a special effect. One example from I.105 describing a ship at sea during a storm has Virgil violating metrical standards to place a single-syllable word at the end of the line: The boat "gives its side to the waves; there comes next in a heap a steep mountain of water." By placing the monosyllable mons at the end of the line, Virgil interrupts the usual "shave and a haircut" pattern to produce a jarring rhythm, an effect that echoes the crash of a large wave against the side of a ship. The Roman poet Horace uses a similar trick to highlight the comedic irony that "Mountains will be in labor, and bring forth a ridiculous mouse" in this famous line from his Ars Poetica (line 139): Another amusing example that comments
galaxy of the Milky Way Galaxy, located at a distance of 179,000 light-years. It has been deformed by its gravitational interactions with the larger Milky Way. In 1987, it became host to SN 1987A, the first supernova of 1987 and the closest since 1604. This 25,000-light-year-wide galaxy contains over 10,000 million stars. All coordinates given are for Epoch J2000.0. N 180B is an emission nebula located in the Large Magellanic Cloud. NGC 1566 (RA 04h 20m 00s Dec -56° 56.3′) is a face-on spiral galaxy. It gives its name to the NGC 1566 Group of galaxies. NGC 1755 (RA 04h 55m 13s Dec -68° 12.2′) is a globular cluster. NGC 1763 (RA 04h 56m 49s Dec -68° 24.5′) is a bright nebula associated with three type B stars. NGC 1820 (RA 05h 04m 02s Dec -67° 15.9′) is an open cluster. NGC 1850 (RA 05h 08m 44s Dec -68° 45.7′) is a globular cluster. NGC 1854 (RA 05h 09m 19s Dec -68° 50.8′) is a globular cluster. NGC 1869 (RA 05h 13m 56s Dec -67° 22.8′) is an open cluster. NGC 1901 (RA 05h 18m 15s Dec -68° 26.2′) is an open cluster. NGC 1910 (RA 05h 18m 43s Dec -69° 13.9′) is an open cluster. NGC 1936 (RA 05h 22m 14s Dec -67° 58.7′) is a bright nebula and is one of four NGC objects in close proximity, the others being NGC 1929, NGC 1934 and NGC 1935. NGC 1978 (RA 05h 28m 36s Dec -66° 14.0′) is an open cluster. NGC 2002 (RA 05h 30m 17s Dec -66° 53.1′) is an open cluster. NGC 2014 (RA 05h 44m 12.7s Dec −67° 42′ 57″) is a red emission nebula. NGC 2020 (RA 05h 44m 12.7s Dec −67° 42′ 57″) is an HII region surrounding a Wolf–Rayet star. NGC 2027 (RA 05h 35m 00s Dec -66° 55.0′) is an open cluster. NGC 2032 (RA 05h 35m 21s Dec -67° 34.1′; also known as "Seagull Nebula") is a nebula complex that contains four NGC designations: NGC 2029, NGC 2032, NGC 2035 and NGC 2040. NGC 2074 (RA 05h 39m 03.0s, Dec −69° 29′ 54″) is an emission nebula. NGC 2080, also called the "Ghost Head Nebula", is an emission nebula that is 50 light-years wide in the Large Magellanic Cloud. It is named for the two distinct white patches that it possesses, which are regions of recent star formation. The western portion is colored green from doubly ionized oxygen, the southern portion is red from hydrogen alpha emissions, and the center region is colored yellow from both oxygen and hydrogen emissions. The western white patch, A1, has one massive, recently formed star inside. The eastern patch, A2, has several stars hidden in its dust. Tarantula Nebula is in the Large Magellanic Cloud, named for its spiderlike shape. It is also designated 30	Way/Magellanic Cloud system. Dorado is also the location of the South Ecliptic pole, which lies near the fish's head. The pole was called "Polus Doradinalis" by Willem Jansson Blaeu. Deep-sky objects Because Dorado contains part of the Large Magellanic Cloud, it is rich in deep sky objects. The Large Magellanic Cloud, 25,000 light-years in diameter, is a satellite galaxy of the Milky Way Galaxy, located at a distance of 179,000 light-years. It has been deformed by its gravitational interactions with the larger Milky Way. In 1987, it became host to SN 1987A, the first supernova of 1987 and the closest since 1604. This 25,000-light-year-wide galaxy contains over 10,000 million stars. All coordinates given are for Epoch J2000.0. N 180B is an emission nebula located in the Large Magellanic Cloud. NGC 1566 (RA 04h 20m 00s Dec -56° 56.3′) is a face-on spiral galaxy. It gives its name to the NGC 1566 Group of galaxies. NGC 1755 (RA 04h 55m 13s Dec -68° 12.2′) is a globular cluster. NGC 1763 (RA 04h 56m 49s Dec -68° 24.5′) is a bright nebula associated with three type B stars. NGC 1820 (RA 05h 04m 02s Dec -67° 15.9′) is an open cluster. NGC 1850 (RA 05h 08m 44s Dec -68° 45.7′) is a globular cluster. NGC 1854 (RA 05h 09m 19s Dec -68° 50.8′) is a globular cluster. NGC 1869 (RA 05h 13m 56s Dec -67° 22.8′) is an open cluster. NGC 1901 (RA 05h 18m 15s Dec -68° 26.2′) is an open cluster. NGC 1910 (RA 05h 18m 43s Dec -69° 13.9′) is an open cluster. NGC 1936 (RA 05h 22m 14s Dec -67° 58.7′) is a bright nebula and is one of four NGC objects in close proximity, the others being NGC 1929, NGC 1934 and NGC 1935. NGC 1978 (RA 05h 28m 36s Dec -66° 14.0′) is an open cluster. NGC 2002 (RA 05h 30m 17s Dec -66° 53.1′) is an open cluster. NGC 2014 (RA 05h 44m 12.7s Dec −67° 42′ 57″) is a red emission nebula. NGC 2020 (RA 05h 44m 12.7s Dec −67° 42′ 57″) is an HII region surrounding a Wolf–Rayet star. NGC 2027 (RA 05h 35m 00s Dec -66° 55.0′) is an open cluster. NGC 2032 (RA 05h 35m 21s Dec -67° 34.1′; also known as "Seagull Nebula") is a nebula complex that contains four NGC designations: NGC 2029, NGC 2032, NGC 2035 and NGC 2040. NGC 2074 (RA 05h 39m 03.0s, Dec
by Solon in the early 6th century BC, with the exception of the homicide law. Homicide law After much debate, the Athenians decided to revise the laws, including the homicide law, in 409 BC. The homicide law is a highly fragmented inscription, but states that it is up to the victim's relatives to prosecute a killer. According to the preserved part of the inscription, unintentional homicides received a sentence of exile. It is not clear whether Draco's law specified the punishment for intentional homicide. In 409 BC, intentional homicide was punished by death, but Draco's law begins, 'καὶ ἐὰμ μὲ ‘κ [π]ρονοί[α]ς [κ]τ[ένει τίς τινα, φεύγ]ε[ν]', which is ambiguous and difficult to translate. One possible translation offers, "Even if a man not intentionally kills another, he is exiled". Council of Four Hundred Draco introduced the lot-chosen Council of Four Hundred, distinct from the Areopagus, which evolved in later constitutions to play a large role in Athenian democracy. Aristotle notes that Draco, while having the laws written, merely legislated for an existing unwritten Athenian constitution such as setting exact qualifications for eligibility for office. Draco extended the franchise to all free men who could furnish themselves with a set of military equipment. They elected the Council of Four Hundred from among their number; nine archons and the treasurers were drawn from persons possessing an unencumbered property of not less than ten minas, the generals (strategoi) and commanders of cavalry (hipparchoi) from those who could show an unencumbered property of not less than a hundred minas and had children born in lawful wedlock over ten years of age. Thus, in the event of their death, their estate could pass to a competent heir. These officers were required to hold to account the prytanes (councillors), strategoi (generals) and hipparchoi (cavalry officers) of the preceding year until their accounts had been audited. "The Council of Areopagus was guardian of the laws, and kept watch over the magistrates to see that they executed their offices in accordance with the laws. Any person who felt himself wronged might lay an information before the Council of Areopagus, on declaring what law was broken by the wrong done to him. But, as has been said before, loans were secured upon the persons of the debtors, and the land was in the hands of a few." See also Ancient Greek law Hammurabi, a Babylonian who wrote some of the earliest codes of law Cruel and unusual punishment Retributive justice List of Ancient Greeks List of eponymous laws (those named after their inventor) References Further reading External links Decree to republish Draco’s law on homicide—Translation of original inscription 7th-century BC Athenians Ancient Greek law Ancient legislators Archaic Athens Government of ancient Athens Year of birth unknown	rules or laws, in Greek, English, and other European languages. Life During the 39th Olympiad, in 622 or 621 BC, Draco established the legal code with which he is identified. Little is known about Draco’s life. He may have belonged to the Greek nobility of Attica prior to the period of the Seven Sages of Greece, as per the 10th-century Byzantine encyclopedia, the Suda. The Suda chronicles a folkloric story of his death in the Aeginetan theatre: in a traditional ancient Greek show of approval, his supporters "threw so many hats and shirts and cloaks on his head that he suffocated, and was buried in that same theatre". The truth about his death is still unclear, but it is known that Draco was driven out of Athens by the Athenians to the neighbouring island of Aegina, where he spent the remainder of his life. Draconian constitution The laws ( – thesmoi) that he laid were the first written constitution of Athens. So that no one would be unaware of them, they were posted on wooden tablets ( – axones), where they were preserved for almost two centuries on steles of the shape of four-sided pyramids ( – kyrbeis). The tablets were called axones, perhaps because they could be pivoted along the pyramid's axis to read any side. The constitution featured several major innovations: Instead of oral laws known to a special class, arbitrarily applied and interpreted, all laws were written, thus being made known to all literate
properties. This approach can also be used to compute determinants by simplifying the matrices in question. Leibniz formula The Leibniz formula for the determinant of a matrix is the following: The rule of Sarrus is a mnemonic for this formula: the sum of the products of three diagonal north-west to south-east lines of matrix elements, minus the sum of the products of three diagonal south-west to north-east lines of elements, when the copies of the first two columns of the matrix are written beside it as in the illustration: This scheme for calculating the determinant of a matrix does not carry over into higher dimensions. n × n matrices The Leibniz formula for the determinant of an -matrix is a more involved, but related expression. It is an expression involving the notion of permutations and their signature. A permutation of the set is a function that reorders this set of integers. The value in the -th position after the reordering is denoted by . The set of all such permutations, the so-called symmetric group, is denoted . The signature of is defined to be whenever the reordering given by can be achieved by successively interchanging two entries an even number of times, and whenever it can be achieved by an odd number of such interchanges. Given the matrix and a permutation , the product is also written more briefly using Pi notation as . Using these notions, the definition of the determinant using the Leibniz formula is then a sum involving all permutations, where each summand is a product of entries of the matrix, multiplied with a sign depending on the permutation. The following table unwinds these terms in the case . In the first column, a permutation is listed according to its values. For example, in the second row, the permutation satisfies . It can be obtained from the standard order (1, 2, 3) by a single exchange (exchanging the second and third entry), so that its signature is . The sum of the six terms in the third column then reads This gives back the formula for -matrices above. For a general -matrix, the Leibniz formula involves (n factorial) summands, each of which is a product of n entries of the matrix. The Leibniz formula can also be expressed using a summation in which not only permutations, but all sequences of indices in the range occur. To do this, one uses the Levi-Civita symbol instead of the sign of a permutation This gives back the formula above since the Levi-Civita symbol is zero if the indices do not form a permutation. Properties of the determinant Characterization of the determinant The determinant can be characterized by the following three key properties. To state these, it is convenient to regard an -matrix A as being composed of its columns, so denoted as where the column vector (for each i) is composed of the entries of the matrix in the i-th column. , where is an identity matrix. The determinant is multilinear: if the jth column of a matrix is written as a linear combination of two column vectors v and w and a number r, then the determinant of A is expressible as a similar linear combination: The determinant is alternating: whenever two columns of a matrix are identical, its determinant is 0: If the determinant is defined using the Leibniz formula as above, these three properties can be proved by direct inspection of that formula. Some authors also approach the determinant directly using these three properties: it can be shown that there is exactly one function that assigns to any -matrix A a number that satisfies these three properties. This also shows that this more abstract approach to the determinant yields the same definition as the one using the Leibniz formula. To see this it suffices to expand the determinant by multi-linearity in the columns into a (huge) linear combination of determinants of matrices in which each column is a standard basis vector. These determinants are either 0 (by property 9) or else ±1 (by properties 1 and 12 below), so the linear combination gives the expression above in terms of the Levi-Civita symbol. While less technical in appearance, this characterization cannot entirely replace the Leibniz formula in defining the determinant, since without it the existence of an appropriate function is not clear. Immediate consequences These rules have several further consequences: The determinant is a homogeneous function, i.e., (for an matrix ). Interchanging any pair of columns of a matrix multiplies its determinant by −1. This follows from the determinant being multilinear and alternating (properties 2 and 3 above): This formula can be applied iteratively when several columns are swapped. For example Yet more generally, any permutation of the columns multiplies the determinant by the sign of the permutation. If some column can be expressed as a linear combination of the other columns (i.e. the columns of the matrix form a linearly dependent set), the determinant is 0. As a special case, this includes: if some column is such that all its entries are zero, then the determinant of that matrix is 0. Adding a scalar multiple of one column to another column does not change the value of the determinant. This is a consequence of multilinearity and being alternative: by multilinearity the determinant changes by a multiple of the determinant of a matrix with two equal columns, which determinant is 0, since the determinant is alternating. If is a triangular matrix, i.e. , whenever or, alternatively, whenever , then its determinant equals the product of the diagonal entries: Indeed, such a matrix can be reduced, by appropriately adding multiples of the columns with fewer nonzero entries to those with more entries, to a diagonal matrix (without changing the determinant). For such a matrix, using the linearity in each column reduces to the identity matrix, in which case the stated formula holds by the very first characterizing property of determinants. Alternatively, this formula can also be deduced from the Leibniz formula, since the only permutation which gives a non-zero contribution is the identity permutation. Example These characterizing properties and their consequences listed above are both theoretically significant, but can also be used to compute determinants for concrete matrices. In fact, Gaussian elimination can be applied to bring any matrix into upper triangular form, and the steps in this algorithm affect the determinant in a controlled way. The following concrete example illustrates the computation of the determinant of the matrix using that method: Combining these equalities gives Transpose The determinant of the transpose of equals the determinant of A: . This can be proven by inspecting the Leibniz formula. This implies that in all the properties mentioned above, the word "column" can be replaced by "row" throughout. For example, viewing an matrix as being composed of n rows, the determinant is an n-linear function. Multiplicativity and matrix groups Thus the determinant is a multiplicative map, i.e., for square matrices and of equal size, the determinant of a matrix product equals the product of their determinants: This key fact can be proven by observing that, for a fixed matrix , both sides of the equation are alternating and multilinear as a function depending on the columns of . Moreover, they both take the value when is the identity matrix. The above-mentioned unique characterization of alternating multilinear maps therefore shows this claim. A matrix is invertible precisely if its determinant is nonzero. This follows from the multiplicativity of and the formula for the inverse involving the adjugate matrix mentioned below. In this event, the determinant of the inverse matrix is given by . In particular, products and inverses of matrices with non-zero determinant (respectively, determinant one) still have this property. Thus, the set of such matrices (of fixed size ) forms a group known as the general linear group (respectively, a subgroup called the special linear group . More generally, the word "special" indicates the subgroup of another matrix group of matrices of determinant one. Examples include the special orthogonal group (which if n is 2 or 3 consists of all rotation matrices), and the special unitary group. The Cauchy–Binet formula is a generalization of that product formula for rectangular matrices. This formula can also be recast as a multiplicative formula for compound matrices whose entries are the determinants of all quadratic submatrices of a given matrix. Laplace expansion Laplace expansion expresses the determinant of a matrix in terms of determinants of smaller matrices, known as its minors. The minor is defined to be the determinant of the -matrix that results from by removing the -th row and the -th column. The expression is known as a cofactor. For every , one has the equality which is called the Laplace expansion along the th row. For example, the Laplace expansion along the first row () gives the following formula: Unwinding the determinants of these -matrices gives back the Leibniz formula mentioned above. Similarly, the Laplace expansion along the -th column is the equality Laplace expansion can be used iteratively for computing determinants, but this approach is inefficient for large matrices. However, it is useful for computing the determinants of highly symmetric matrix such as the Vandermonde matrix This determinant has been applied, for example, in the proof of Baker's theorem in the theory of transcendental numbers. Adjugate matrix The adjugate matrix is the transpose of the matrix of the cofactors, that is, For every matrix, one has Thus the adjugate matrix can be used for expressing the inverse of a nonsingular matrix: Block matrices The formula for the determinant of a -matrix above continues to hold, under appropriate further assumptions, for a block matrix, i.e., a matrix composed of four submatrices of dimension , , and , respectively. The easiest such formula, which can be proven using either the Leibniz formula or a factorization involving the Schur complement, is If is invertible (and similarly if is invertible), one has If is a -matrix, this simplifies to . If the blocks are square matrices of the same size further formulas hold. For example, if and commute (i.e., ), then there holds This formula has been generalized to matrices composed of more than blocks, again under appropriate commutativity conditions among the individual blocks. For and , the following formula holds (even if and do not commute) Sylvester's determinant theorem Sylvester's determinant theorem states that for A, an matrix, and B, an matrix (so that A and B have dimensions allowing them to be multiplied in either order forming a square matrix): where Im and In are the and identity matrices, respectively. From this general result several consequences follow. Sum The determinant of the sum of two square matrices of the same size is not in general expressible in terms of the determinants of A and of B. However, for positive semidefinite matrices , and of equal size, , for with the corollary Properties of the determinant in relation to other notions Eigenvalues and characteristic polynomial The determinant is closely related to two other central concepts in linear algebra, the eigenvalues and the characteristic polynomial of a matrix. Let be an -matrix with complex entries with eigenvalues . (Here it is understood that an eigenvalue with algebraic multiplicity occurs times in this list.) Then the determinant of is the product of all eigenvalues, The product of all non-zero eigenvalues is referred to as pseudo-determinant. The characteristic polynomial is defined as Here, is the indeterminate of the polynomial and is the identity matrix of the same size as . By means of this polynomial, determinants can be used to find the eigenvalues of the matrix : they are precisely the roots of this polynomial, i.e., those complex numbers such that A Hermitian matrix is positive definite if all its eigenvalues are positive. Sylvester's criterion asserts that this is equivalent to the determinants of the submatrices being positive, for all between and . Trace The trace tr(A) is by definition the sum of the diagonal entries of and also equals the sum of the eigenvalues. Thus, for complex matrices , or, for real matrices , Here exp() denotes the matrix exponential of , because every eigenvalue of corresponds to the eigenvalue exp() of exp(). In particular, given any logarithm of , that is, any matrix satisfying the determinant of is given by For example, for , , and , respectively, cf. Cayley-Hamilton theorem. Such expressions are deducible from combinatorial arguments, Newton's identities, or the Faddeev–LeVerrier algorithm. That is, for generic , the signed constant term of the characteristic polynomial, determined recursively from In the general case, this may also be obtained from where the sum is taken over the set of all integers satisfying the equation The formula can be expressed in terms of the complete exponential Bell polynomial of n arguments sl = −(l – 1)! tr(Al) as	satisfies these three properties. This also shows that this more abstract approach to the determinant yields the same definition as the one using the Leibniz formula. To see this it suffices to expand the determinant by multi-linearity in the columns into a (huge) linear combination of determinants of matrices in which each column is a standard basis vector. These determinants are either 0 (by property 9) or else ±1 (by properties 1 and 12 below), so the linear combination gives the expression above in terms of the Levi-Civita symbol. While less technical in appearance, this characterization cannot entirely replace the Leibniz formula in defining the determinant, since without it the existence of an appropriate function is not clear. Immediate consequences These rules have several further consequences: The determinant is a homogeneous function, i.e., (for an matrix ). Interchanging any pair of columns of a matrix multiplies its determinant by −1. This follows from the determinant being multilinear and alternating (properties 2 and 3 above): This formula can be applied iteratively when several columns are swapped. For example Yet more generally, any permutation of the columns multiplies the determinant by the sign of the permutation. If some column can be expressed as a linear combination of the other columns (i.e. the columns of the matrix form a linearly dependent set), the determinant is 0. As a special case, this includes: if some column is such that all its entries are zero, then the determinant of that matrix is 0. Adding a scalar multiple of one column to another column does not change the value of the determinant. This is a consequence of multilinearity and being alternative: by multilinearity the determinant changes by a multiple of the determinant of a matrix with two equal columns, which determinant is 0, since the determinant is alternating. If is a triangular matrix, i.e. , whenever or, alternatively, whenever , then its determinant equals the product of the diagonal entries: Indeed, such a matrix can be reduced, by appropriately adding multiples of the columns with fewer nonzero entries to those with more entries, to a diagonal matrix (without changing the determinant). For such a matrix, using the linearity in each column reduces to the identity matrix, in which case the stated formula holds by the very first characterizing property of determinants. Alternatively, this formula can also be deduced from the Leibniz formula, since the only permutation which gives a non-zero contribution is the identity permutation. Example These characterizing properties and their consequences listed above are both theoretically significant, but can also be used to compute determinants for concrete matrices. In fact, Gaussian elimination can be applied to bring any matrix into upper triangular form, and the steps in this algorithm affect the determinant in a controlled way. The following concrete example illustrates the computation of the determinant of the matrix using that method: Combining these equalities gives Transpose The determinant of the transpose of equals the determinant of A: . This can be proven by inspecting the Leibniz formula. This implies that in all the properties mentioned above, the word "column" can be replaced by "row" throughout. For example, viewing an matrix as being composed of n rows, the determinant is an n-linear function. Multiplicativity and matrix groups Thus the determinant is a multiplicative map, i.e., for square matrices and of equal size, the determinant of a matrix product equals the product of their determinants: This key fact can be proven by observing that, for a fixed matrix , both sides of the equation are alternating and multilinear as a function depending on the columns of . Moreover, they both take the value when is the identity matrix. The above-mentioned unique characterization of alternating multilinear maps therefore shows this claim. A matrix is invertible precisely if its determinant is nonzero. This follows from the multiplicativity of and the formula for the inverse involving the adjugate matrix mentioned below. In this event, the determinant of the inverse matrix is given by . In particular, products and inverses of matrices with non-zero determinant (respectively, determinant one) still have this property. Thus, the set of such matrices (of fixed size ) forms a group known as the general linear group (respectively, a subgroup called the special linear group . More generally, the word "special" indicates the subgroup of another matrix group of matrices of determinant one. Examples include the special orthogonal group (which if n is 2 or 3 consists of all rotation matrices), and the special unitary group. The Cauchy–Binet formula is a generalization of that product formula for rectangular matrices. This formula can also be recast as a multiplicative formula for compound matrices whose entries are the determinants of all quadratic submatrices of a given matrix. Laplace expansion Laplace expansion expresses the determinant of a matrix in terms of determinants of smaller matrices, known as its minors. The minor is defined to be the determinant of the -matrix that results from by removing the -th row and the -th column. The expression is known as a cofactor. For every , one has the equality which is called the Laplace expansion along the th row. For example, the Laplace expansion along the first row () gives the following formula: Unwinding the determinants of these -matrices gives back the Leibniz formula mentioned above. Similarly, the Laplace expansion along the -th column is the equality Laplace expansion can be used iteratively for computing determinants, but this approach is inefficient for large matrices. However, it is useful for computing the determinants of highly symmetric matrix such as the Vandermonde matrix This determinant has been applied, for example, in the proof of Baker's theorem in the theory of transcendental numbers. Adjugate matrix The adjugate matrix is the transpose of the matrix of the cofactors, that is, For every matrix, one has Thus the adjugate matrix can be used for expressing the inverse of a nonsingular matrix: Block matrices The formula for the determinant of a -matrix above continues to hold, under appropriate further assumptions, for a block matrix, i.e., a matrix composed of four submatrices of dimension , , and , respectively. The easiest such formula, which can be proven using either the Leibniz formula or a factorization involving the Schur complement, is If is invertible (and similarly if is invertible), one has If is a -matrix, this simplifies to . If the blocks are square matrices of the same size further formulas hold. For example, if and commute (i.e., ), then there holds This formula has been generalized to matrices composed of more than blocks, again under appropriate commutativity conditions among the individual blocks. For and , the following formula holds (even if and do not commute) Sylvester's determinant theorem Sylvester's determinant theorem states that for A, an matrix, and B, an matrix (so that A and B have dimensions allowing them to be multiplied in either order forming a square matrix): where Im and In are the and identity matrices, respectively. From this general result several consequences follow. Sum The determinant of the sum of two square matrices of the same size is not in general expressible in terms of the determinants of A and of B. However, for positive semidefinite matrices , and of equal size, , for with the corollary Properties of the determinant in relation to other notions Eigenvalues and characteristic polynomial The determinant is closely related to two other central concepts in linear algebra, the eigenvalues and the characteristic polynomial of a matrix. Let be an -matrix with complex entries with eigenvalues . (Here it is understood that an eigenvalue with algebraic multiplicity occurs times in this list.) Then the determinant of is the product of all eigenvalues, The product of all non-zero eigenvalues is referred to as pseudo-determinant. The characteristic polynomial is defined as Here, is the indeterminate of the polynomial and is the identity matrix of the same size as . By means of this polynomial, determinants can be used to find the eigenvalues of the matrix : they are precisely the roots of this polynomial, i.e., those complex numbers such that A Hermitian matrix is positive definite if all its eigenvalues are positive. Sylvester's criterion asserts that this is equivalent to the determinants of the submatrices being positive, for all between and . Trace The trace tr(A) is by definition the sum of the diagonal entries of and also equals the sum of the eigenvalues. Thus, for complex matrices , or, for real matrices , Here exp() denotes the matrix exponential of , because every eigenvalue of corresponds to the eigenvalue exp() of exp(). In particular, given any logarithm of , that is, any matrix satisfying the determinant of is given by For example, for , , and , respectively, cf. Cayley-Hamilton theorem. Such expressions are deducible from combinatorial arguments, Newton's identities, or the Faddeev–LeVerrier algorithm. That is, for generic , the signed constant term of the characteristic polynomial, determined recursively from In the general case, this may also be obtained from where the sum is taken over the set of all integers satisfying the equation The formula can be expressed in terms of the complete exponential Bell polynomial of n arguments sl = −(l – 1)! tr(Al) as This formula can also be used to find the determinant of a matrix with multidimensional indices and . The product and trace of such matrices are defined in a natural way as An important arbitrary dimension identity can be obtained from the Mercator series expansion of the logarithm when the expansion converges. If every eigenvalue of A is less than 1 in absolute value, where is the identity matrix. More generally, if is expanded as a formal power series in then all coefficients of for are zero and the remaining polynomial is . Upper and lower bounds For a positive definite matrix , the trace operator gives the following tight lower and upper bounds on the log determinant with equality if and only if . This relationship can be derived via the formula for the KL-divergence between two multivariate normal distributions. Also, These inequalities can be proved by expressing the traces and the determinant in terms of the eigenvalues. As such, they represent the well-known fact that the harmonic mean is less than the geometric mean, which is less than the arithmetic mean, which is, in turn, less than the root mean square. Derivative The Leibniz formula shows that the determinant of real (or analogously for complex) square matrices is a polynomial function from to . In particular, it is everywhere differentiable. Its derivative can be expressed using Jacobi's formula: where denotes the adjugate of . In particular, if is invertible, we have Expressed in terms of the entries of , these are Yet another equivalent formulation is , using big O notation. The special case where , the identity matrix, yields This identity is used in describing Lie algebras associated to certain matrix Lie groups. For example, the special linear group is defined by the equation . The above formula shows that its Lie algebra is the special linear Lie algebra consisting of those matrices having trace zero. Writing a -matrix as where are column vectors of length 3, then the gradient over one of the three vectors may be written as the cross product of the other two: History Historically, determinants were used long before matrices: A determinant was originally defined as a property of a system of linear equations. The determinant "determines" whether the system has a unique solution (which occurs precisely if the determinant is non-zero). In this sense, determinants were first used in the Chinese mathematics textbook The Nine Chapters on the Mathematical Art (九章算術, Chinese scholars, around the 3rd century BCE). In Europe, solutions of linear systems of two equations were expressed by Cardano in 1545 by a determinant-like entity. Determinants proper originated from the work of Seki Takakazu in 1683 in Japan and parallelly of Leibniz in 1693. stated, without proof, Cramer's rule. Both Cramer and also were led to determinants by the question of plane curves passing through a given set of points. Vandermonde (1771) first recognized determinants as independent functions. gave the general method of expanding a determinant in terms of its complementary minors: Vandermonde had already given a special case. Immediately following, Lagrange (1773) treated determinants of the second and third order and applied it to questions of elimination theory; he proved many special cases of general identities. Gauss (1801) made the next advance. Like Lagrange, he made much use of determinants in the theory of numbers. He introduced the word "determinant" (Laplace had used "resultant"), though not in the present signification, but rather as applied to the discriminant of a quantic. Gauss also arrived at the notion of reciprocal (inverse) determinants, and came very near the multiplication theorem. The next contributor of importance is Binet (1811, 1812), who formally stated the theorem relating to the product of two matrices of m columns and n rows, which for the special case of reduces to the multiplication theorem. On the same day (November 30, 1812) that Binet presented his paper to the Academy, Cauchy also presented one on the subject. (See Cauchy–Binet formula.) In this he used the word "determinant" in its present sense, summarized and simplified what was then known on the subject, improved the notation, and gave the multiplication theorem with a proof more satisfactory than Binet's. With him begins the theory in its generality. used the functional determinant which Sylvester later called the Jacobian. In his memoirs in Crelle's Journal for 1841 he specially treats this subject, as well as the class of alternating functions which Sylvester has called alternants. About the time of Jacobi's last memoirs, Sylvester (1839) and Cayley began their work. introduced the modern notation for the determinant using vertical bars. The study of special forms of determinants has been the natural result of the completion of the general theory. Axisymmetric determinants have been studied by Lebesgue, Hesse, and Sylvester; persymmetric determinants by Sylvester and Hankel; circulants by Catalan, Spottiswoode, Glaisher, and Scott; skew determinants and Pfaffians, in connection with the theory of orthogonal transformation, by Cayley; continuants by Sylvester; Wronskians (so called by Muir) by Christoffel and Frobenius; compound determinants by Sylvester, Reiss, and Picquet; Jacobians and Hessians by Sylvester; and symmetric gauche determinants by Trudi. Of the textbooks on the subject Spottiswoode's was the first. In America, Hanus (1886), Weld (1893), and Muir/Metzler (1933) published treatises. Applications Cramer's rule Determinants can be used to describe the solutions of a linear system of equations, written in matrix form as . This equation has a unique solution if and only if is nonzero. In this case, the solution is given by Cramer's rule: where is the matrix formed by replacing the -th column of by the column vector . This follows immediately by column expansion of the determinant, i.e. where the vectors are the columns of A. The rule is also implied by the identity Cramer's rule can be implemented in time, which is comparable to more common methods of solving systems of linear equations, such as LU, QR, or singular value decomposition. Linear independence Determinants can be used to characterize linearly dependent vectors: is zero if and only if the column vectors (or, equivalently, the row vectors) of the matrix are linearly dependent. For example, given two linearly independent vectors , a third vector lies in the plane spanned by the former two vectors exactly if the determinant of the -matrix consisting of the three vectors is zero. The same idea is also used in the theory of differential equations: given functions (supposed to be times differentiable), the Wronskian is defined to be It is non-zero (for some ) in a specified interval if and only if the given functions and all their derivatives up to order are linearly independent. If it can be shown that the Wronskian is zero everywhere on an interval then, in the case of analytic functions, this implies the given functions are linearly dependent. See the Wronskian and linear independence. Another such use of the determinant is the resultant, which gives a criterion when two polynomials have a common root. Orientation of a basis The determinant can be thought of as assigning a number to every sequence of n vectors in Rn, by using the square matrix whose columns are the given vectors. For instance, an orthogonal matrix with entries in Rn represents an orthonormal basis in Euclidean space. The determinant of such a matrix determines whether the orientation of the basis is consistent with or opposite to the orientation of the standard basis. If the determinant is +1, the basis has the same orientation. If it is −1, the basis has the opposite orientation. More generally, if the determinant of A is positive, A represents an orientation-preserving linear transformation (if A is an orthogonal or matrix, this is a rotation), while if it is negative, A switches the orientation of the basis. Volume and Jacobian determinant As pointed out above, the absolute value of the determinant of real vectors is equal to the volume of the parallelepiped spanned by those vectors. As a consequence, if is the linear map given by multiplication with a matrix , and is any measurable subset, then the volume of is given by times the volume of . More generally, if the linear map is represented by the -matrix , then the -dimensional volume of is given by: By calculating the volume of the tetrahedron bounded by four points, they can be used to identify skew lines. The volume of any tetrahedron, given its vertices , , or any other combination of pairs of vertices that form a spanning tree over the vertices. For a general differentiable function, much of the above carries over by considering the Jacobian matrix of f. For the Jacobian matrix is the matrix whose entries are given by the partial derivatives Its determinant, the Jacobian determinant, appears in the higher-dimensional version of integration by substitution: for suitable functions f and an open subset U of Rn (the domain of f), the integral over f(U) of some other function is given by The Jacobian also occurs in the inverse function theorem. When applied to the field of Cartography, the determinant can be used
economy. Ricardo advocated for the productive powers of labor to be held in high concern as the most influential of devices that played a role in the progression of the American Economy along with others. In addition, Ricardo made notable advancements in the concept build involving reactions in the open market when considering banking altercations, stock investments, or other considerable impacting events. Ricardo wanted to establish a firm ground between the bank and the control over monetary policy because there was power within the banking system that Ricardo believed needed to be considered carefully. In 1816, Ricardo said “In the present state of the law, they have the power, without any control whatever, of increasing or reducing the circulation in any degree they may think proper: a power which should neither be entrusted to the State itself, nor to anybody in it; as there can be no security for the uniformity in the value of the currency, when its augmentation or diminution depends solely on the will of the issuers.” Ricardo felt the circulation of money and the decision behind how much is available at any time should not be entrusted to either the State, or any individual. Ricardo argued for the most even distribution possible with the highest control readily available. David Ricardo, The Principles of Political Economy and Taxation Value theory David Ricardo worked to fix the issues he felt were most concerning with Adam Smith’s Labour Theory of Value. Both men worked with the assumption that land, labour, and capital were the three basic factors of production. However, Smith narrowed in on labour as the determinant of value. Ricardo believes that with production having 3 main factors it is impossible for only one of them to determine value on its own. Ricardo illustrates his point by adapting Smith's deer beaver analogy to show that even when labour is the only factor of production the hardship and tools of the labour will drive a wedge in the relative value of the good. Due to his criticisms of the Labour Theory of Value George Stigler called his theory a "93% labor theory of value". Ricardo's most famous work is his Principles of Political Economy and Taxation (1817). He advanced a labour theory of value: The value of a commodity, or the quantity of any other commodity for which it will exchange, depends on the relative quantity of labour which is necessary for its production, and not on the greater or less compensation which is paid for that labour. Ricardo's note to Section VI: Mr. Malthus appears to think that it is a part of my doctrine, that the cost and value of a thing be the same;—it is, if he means by cost, "cost of production" including profit. Rent Ricardo contributed to the development of theories of rent, wages, and profits. He defined rent as "the difference between the produce obtained by the employment of two equal quantities of capital and labour." Ricardo believed that the process of economic development, which increased land use and eventually led to the cultivation of poorer land, principally benefited landowners. According to Ricardo, such premium over "real social value" that is reaped due to ownership constitutes value to an individual but is at best a paper monetary return to "society". The portion of such purely individual benefit that accrues to scarce resources Ricardo labels "rent". Ricardo's theories of wages and profits In his Theory of Profit, Ricardo stated that as real wages increase, real profits decrease because the revenue from the sale of manufactured goods is split between profits and wages. He said in his Essay on Profits, "Profits depend on high or low wages, wages on the price of necessaries, and the price of necessaries chiefly on the price of food." Ricardian theory of international trade Between 1500 and 1750 most economists advocated Mercantilism, which promoted the idea of international trade for the purpose of earning bullion by running a trade surplus with other countries. Ricardo challenged the idea that the purpose of trade was merely to accumulate gold or silver. With "comparative advantage" Ricardo argued in favour of industry specialisation and free trade. He suggested that industry specialization combined with free international trade always produces positive results. This theory expanded on the concept of absolute advantage. Ricardo suggested that there is mutual national benefit from trade even if one country is more competitive in every area than its trading counterpart and that a nation should concentrate resources only in industries where it has a comparative advantage, that is in those industries in which it has the greatest efficiency of production relative to its own alternative uses of resources, rather than industries where it holds a competitive edge compared to rival nations. Ricardo suggested that national industries which were, in fact, mildly profitable and marginally internationally competitive should be jettisoned in favour of the industries that made the best use of limited resources – the assumption being that subsequent economic growth due to better resource use would more than offset any short-run economic dislocation which would result from closing mildly profitable and marginally competitive national industries. Ricardo attempted to prove theoretically that international trade is always beneficial. Paul Samuelson called the numbers used in Ricardo's example dealing with trade between England and Portugal the "four magic numbers". "In spite of the fact that the Portuguese could produce both cloth and wine with less amount of labour, Ricardo suggested that both countries would benefit from trade with each other". As for recent extensions of Ricardian models, see Ricardian trade theory extensions. Comparative advantage Ricardo's theory of international trade was reformulated by John Stuart Mill.<ref>Mill, J. S. (1844) Essays on some unsettled questions of political economy. London, John W. Parker; Mill, J. S. (1848) The principles of political economy.</i> (vol. I and II) Boston: C.C.Little & J. Brown.</ref> The term "comparative advantage" was started by J. S. Mill and his contemporaries. John Stuart Mill started a neoclassical turn of international trade theory, i.e. his formulation was inherited by Alfred Marshall and others and contributed to the resurrection of anti-Ricardian concept of law of supply and demand and induce the arrival neoclassical theory of value. New interpretation Ricardo's four magic numbers have long been interpreted as comparison of two ratios of labour (or other input in fixed supply) coefficients. This interpretation is now considered as overly simplistic by modern economists. The point was rediscovered by Roy J. Ruffin in 2002 and re-examined and explained in detail in Andrea Maneschi in 2004. The more flexible approach is now known as the new interpretation, despite having been previously mentioned by Piero Sraffa in 1930 and by Kenzo Yukizawa in 1974. The new interpretation affords a totally new reading of Ricardo's Principles of Political Economy and Taxation with regards to trade theory, although it does not change the mathematics of optimal resource allocation. Protectionism Like Adam Smith, Ricardo was an opponent of protectionism for national economies, especially for agriculture. He believed that the British "Corn Laws" – imposing tariffs on agricultural products – ensured that less-productive domestic land would be cultivated and rents would be driven up . Thus, profits would be directed toward landlords and away from the emerging industrial capitalists. Ricardo believed landlords tended to squander their wealth on luxuries, rather than invest. He believed the Corn Laws were leading to the stagnation of the British economy. In 1846, his nephew John Lewis Ricardo, MP for Stoke-upon-Trent, advocated free trade and the repeal of the Corn Laws. Modern empirical analysis of the Corn Laws yields mixed results. Parliament repealed the Corn Laws in 1846. Technological change Ricardo was concerned about the impact of technological change on labour in the short-term. In 1821, he wrote that he had become "convinced that the substitution of machinery for human labour, is often very injurious to the interests of the class of labourers," and that "the opinion entertained by the labouring class, that the employment of machinery is frequently detrimental to their interests, is not founded on prejudice and error, but is conformable to the correct principles of political economy." Criticism of the Ricardian theory of trade Ricardo himself was the first to recognize that comparative advantage is a domain-specific theory, meaning that it applies only when certain conditions are met. Ricardo noted that the theory applies only in situations where capital is immobile. Regarding his famous example, he wrote: it would undoubtedly be advantageous to the capitalists [and consumers] of England… [that] the wine and cloth should both be made in Portugal [and that] the capital and labour of England employed in making cloth should be removed to Portugal for that purpose. Ricardo recognized that applying his theory in situations where capital was mobile would result in offshoring, and thereby economic decline and job loss. To correct for this, he argued that (i) "most men of property [will be] satisfied with a low rate of profits in their own country, rather than seek[ing] a more advantageous employment for their wealth in foreign nations", and (ii) capital was functionally immobile. Ricardo's argument in favour of free trade has also been attacked by those who believe trade restriction can be necessary for the economic development of a nation. Utsa Patnaik claims that Ricardian theory of international trade contains a logical fallacy. Ricardo assumed that in both countries two goods are producible and actually are produced, but developed and underdeveloped countries often trade those goods which are not producible in their own country. In these cases, one cannot define which country has comparative advantage. Critics also argue that Ricardo's theory of comparative advantage is flawed in that it assumes production	Portarlington's seat in Parliament for £4,000, as part of the terms of a loan of £25,000. His record in Parliament was that of an earnest reformer. He held the seat until his death five years later. Ricardo was a close friend of James Mill. Other notable friends included Jeremy Bentham and Thomas Malthus, with whom Ricardo had a considerable debate (in correspondence) over such things as the role of landowners in a society. He also was a member of Malthus' Political Economy Club, and a member of the King of Clubs. He was one of the original members of The Geological Society. His youngest sister was author Sarah Ricardo-Porter (e.g., Conversations in Arithmetic). Parliamentary record As MP for Portarlington, he voted with the opposition in support of the liberal movements in Naples, 21 February, and Sicily, 21 June, and for inquiry into the administration of justice in Tobago, 6 June. He divided for repeal of the Blasphemous and Seditious Libels Act, 8 May, inquiry into the Peterloo massacre, 16 May, and abolition of the death penalty for forgery, 25 May 4 June 1821. He adamantly supported the implementation of free trade. He voted against renewal of the sugar duties, 9 Feb, and objected to the higher duty on East as opposed to West Indian produce, 4 May 1821. He opposed the timber duties. He voted silently for parliamentary reform, 25 Apr and 3 June, and spoke in its favour at the Westminster anniversary reform dinner, 23 May 1822. He again voted for criminal law reform, 4 June. David Ricardo believed an increase in imports boosted the happiness of mankind through an increase in the number of goods available for consumption. Ricardo was said to have "possessed an extraordinary quickness in perceiving in the turns of the market any accidental difference which might arise between the relative price of different stocks" and Ricardo was able to grow his wealth dealing in securities during the Revolutionary and Napoleonic wars. As the Napoleonic Wars waged on, David Ricardo developed a disdain for the Corn Laws imposed by the British to encourage exports. Government intervention on the grain trade can be witnessed as far back as the 1400s, and trade has been controlled, regulated, and taxed. England was a capitalist economy involving workers and landlords consuming entire incomes and capital accumulation that depended entirely on capitalists’ profits that were under perpetual pressure during the eighteenth and early nineteenth centuries. Political reform was necessary as agriculture output was struggling to keep the pace of the population growth. The Corn Laws created barriers to imports that increased the subsistence costs that created higher wages. The higher wages reduced the profits and a further effect of a reduction of capital investment and a stationary economy state. Rising rents, attributed to the Corn Laws by Ricardo came at the expense of the nations' economic profits. Free trade was the answer to the stationarity from David Ricardo, and he anticipated Britain would import agriculture products in exchange for manufactured goods. After Ricardo's death, the laws were eventually repealed, and his free-trade plan became public policy in Britain. His friend John Louis Mallett commented: " … he meets you upon every subject that he has studied with a mind made up, and opinions in the nature of mathematical truths. He spoke of parliamentary reform and ballot as a man who would bring such things about, and destroy the existing system tomorrow, if it were in his power, and without the slightest doubt on the result … It is this very quality of the man’s mind, his entire disregard of experience and practice, which makes me doubtful of his opinions on political economy." Death and legacy Ten years after retiring and four years after entering Parliament, Ricardo died from an infection of the middle ear that spread into his brain and induced septicaemia. He was 51. He and his wife Priscilla had eight children together including Osman Ricardo (1795–1881; MP for Worcester 1847–1865), David Ricardo (1803–1864, MP for Stroud 1832–1833) and Mortimer Ricardo, who served as an officer in the Life Guards and was a deputy lieutenant for Oxfordshire. Ricardo is buried in an ornate grave in the churchyard of Saint Nicholas in Hardenhuish, now a suburb of Chippenham, Wiltshire. At the time of his death his assets were estimated at £675,000–£775,000. Ideas He wrote his first economics article at 37, firstly in The Morning Chronicle advocating reduction in the note-issuing of the Bank of England and then publishing The High Price of Bullion, a Proof of the Depreciation of Bank Notes in 1810. He was also an abolitionist, speaking at a meeting of the Court of the East India Company in March 1823, where he said he regarded slavery as a stain on the character of the nation. Banking Adam Smith argued that free commercial banking, such as the banking system in Scotland which had no central bank when Wealth of Nations was written in 1776, was favorable to economic growth. Writing just a few decades later, Ricardo argued for a central bank, a cause that was taken up by his students, including John Stuart Mill, who was known to favor the laissez-faire policies in every place but banking. Ricardo wrote the Plan for the Establishment of a National Bank in 1824 arguing for the autonomy of the central bank as the issuer of money. Ricardo proposes that a ratio of gold and Treasury bills, and a fixed claim (asset) against the government, would secure the central bank's liquidity: The public, or the Government on behalf of the public, is indebted to the Bank in a sum of money larger than the whole amount of Bank notes in circulation; for the Government not only owes the Bank fifteen million, its original capital, which is lent at 3 per cent. interest, but also many more millions which are advanced on Exchequer bills, on half-pau and pension annuities, and on other securities. It is evident, therefore, that if the Government itself were to be the sole issuer of paper money instead of borrowing it of the Bank, the only difference would be with respect to the interest: the Bank would no longer receive interest and the Government would no longer pay it; but all other classes in the community would be exactly in the same position in which they now stand. Ricardo was a man of many trades, economically and financially speaking. Ricardo was able to recognize and identify the problem presented through banking within regulations and debauched standards of approval at certain times. Ricardo knew that banks in rural areas as well as the Bank of England had increased note lending and overall lending in 1810. Through this, Ricardo proved subsequent changes in price level through the market was also affected and thus new regulations needed to be made available. Furthermore, Ricardo was able to understand and distinguish the socioeconomic makeup that created and established parameters around different classes within the economy. Ricardo advocated for the productive powers of labor to be held in high concern as the most influential of devices that played a role in the progression of the American Economy along with others. In addition, Ricardo made notable advancements in the concept build involving reactions in the open market when considering banking altercations, stock investments, or other considerable impacting events. Ricardo wanted to establish a firm ground between the bank and the control over monetary policy because there was power within the banking system that Ricardo believed needed to be considered carefully. In 1816, Ricardo said “In the present state of the law, they have the power, without any control whatever, of increasing or reducing the circulation in any degree they may think proper: a power which should neither be entrusted to the State itself, nor to anybody in it; as there can be no security for the uniformity in the value of the currency, when its augmentation or diminution depends solely on the will of the issuers.” Ricardo felt the circulation of money and the decision behind how much is available at any time should not be entrusted to either the State, or any individual. Ricardo argued for the most even distribution possible with the highest control readily available. David Ricardo, The Principles of Political Economy and Taxation Value theory David Ricardo worked to fix the issues he felt were most concerning with Adam Smith’s Labour Theory of Value. Both men worked with the assumption that land, labour, and capital were the three basic factors of production. However, Smith narrowed in on labour as the determinant of value. Ricardo believes that with production having 3 main factors it is impossible for only one of them to determine value on its own. Ricardo illustrates his point by adapting Smith's deer beaver analogy to show that even when labour is the only factor of production the hardship and tools of the labour will drive a wedge in the relative value of the good. Due to his criticisms of the Labour Theory of Value George Stigler called his theory a "93% labor theory of value". Ricardo's most famous work is his Principles of Political Economy and Taxation (1817). He advanced a labour theory of value: The value of a commodity, or the quantity of any other commodity for which it will exchange, depends on the relative quantity of labour which is necessary for its production, and not on the greater or less compensation which is paid for that labour. Ricardo's note to Section VI: Mr. Malthus appears to think that it is a part of my doctrine, that the cost and value of a thing be the same;—it is, if he means by cost, "cost of production" including profit. Rent Ricardo contributed to the development of theories of rent, wages, and profits. He defined rent as "the difference between the produce obtained by the employment of two equal quantities of capital and labour." Ricardo believed that the process of economic development, which increased land use and eventually led to the cultivation of poorer land, principally benefited landowners. According to Ricardo, such premium over "real social value" that is reaped due to ownership constitutes value to an individual but is at best a paper monetary return to "society". The portion of such purely individual benefit that accrues to scarce resources Ricardo labels "rent". Ricardo's theories of wages and profits In his Theory of Profit, Ricardo stated that as real wages increase, real profits decrease because the revenue from the sale of manufactured goods is split between profits and wages. He said in his Essay on Profits, "Profits depend on high or low wages, wages on the price of necessaries, and the price of necessaries chiefly on the price of food." Ricardian theory of international trade Between 1500 and 1750 most economists advocated Mercantilism, which promoted the idea of international trade for the purpose of earning bullion by running a trade surplus with other countries. Ricardo challenged the idea that the purpose of trade was merely to accumulate gold or silver. With "comparative advantage" Ricardo argued in favour of industry specialisation and free trade. He suggested that industry specialization combined with free international trade always produces positive results. This theory expanded on the concept of absolute advantage. Ricardo suggested that there is mutual national benefit from trade even if one country is more competitive in every area than its trading counterpart and that a nation should concentrate resources only in industries where it has a comparative advantage, that is in those industries in which it has the greatest efficiency of production relative to its own alternative uses of resources, rather than industries where it holds a competitive edge compared to rival nations. Ricardo suggested that national industries which were, in fact, mildly profitable and marginally internationally competitive should be jettisoned in favour of the industries that made the best use of limited resources – the assumption being that subsequent economic growth due to better resource use would more than offset any short-run economic dislocation which would result from closing mildly profitable and marginally competitive national industries. Ricardo attempted to prove theoretically that international trade is always beneficial. Paul Samuelson called the numbers used in Ricardo's example dealing with trade between England and Portugal the "four magic numbers". "In spite of the fact that the Portuguese could produce both cloth and wine with less amount of labour, Ricardo suggested that both countries would benefit from trade with each other". As for recent extensions of Ricardian models, see Ricardian trade theory extensions. Comparative advantage Ricardo's theory of international trade was reformulated by John Stuart Mill.<ref>Mill, J. S. (1844) Essays on some unsettled questions of political economy. London, John
small amateur telescope. The secondary, also described as green, is 10 arcseconds from the primary. Struve 2725, called the "Ghost Double", is a pair that appears similar but dimmer. Its components of magnitudes 7.6 and 8.4 are separated by 6 arcseconds and are 15 arcminutes from Gamma Delphini itself. Delta Delphini is a type A7 IIIp star of magnitude 4.43. Epsilon Delphini, Deneb Dulfim (lit. "tail [of the] Dolphin"), or Aldulfin, is a star of stellar class B6 III and magnitude 4, at 330 ly. Zeta Delphini, blue-white main-sequence star of magnitude 4.6, was in 2014 discovered to have a brown dwarf orbiting around it. Zeta Delphini B has a mass of 50±15 . In Delphinus, in extremes of distance, Gliese 795 is the closest known star at 54.95 ly and rapidly moves east over a period of centuries (863±3 arcseconds per year); whereas the giant of blue colour, W Delphini is at 2203.81 ly at 9.76 magnitude. Its brightness ranges from a magnitude of 12.3 to a magnitude of 9.7 over its variable period as it is a Beta Persei star-type semi-detached system. Other variable stars of large amateur telescopic visibility include R Delphini, a Mira-type variable star with a period of 285.5 days. Its magnitude ranges between a maximum 7.6 and a minimum 13.8. Rho Aquilae at magnitude 4.94 is at about 150 light years. Due to its proper motion it has been in the (round-figure parameter) bounds of the constellation since 1992. HR Delphini was a nova that brightened to magnitude 3.5 in December 1967. It took an unusually long time for the nova to reach peek brightness which indicate that it barely satisfied the conditions for a thermonuclear runaway. Another nova by the name V339 Delphini was detected in 2013; it peaked at magnitude 4.3 and was the first nova observed to produce lithium. Musica, also known by its Flamsteed designation 18 Delphini, is one of the five stars with known planets located in Delphinus. Arion, the planet, is a very dense and massive planet with a mass at least 10.3 times greater than Jupiter. Arion was part of the first NameExoWorlds contest where the public got the opportunity to suggest names for exoplanets and their host stars. Deep-sky objects Its rich Milky Way star field means many modestly deep-sky objects. NGC 6891 is a planetary nebula of magnitude 10.5; another is NGC 6905 or the Blue Flash nebula. NGC 6934 is a globular cluster of magnitude 9.75. At a distance of about 185,000 light-years, the globular cluster NGC 7006 is at the outer reaches of the galaxy. It is also fairly dim at magnitude 11.5. See also Delphinus (Chinese astronomy) Notes Citations References Ian Ridpath and Wil Tirion (2017). Stars and Planets Guide, Collins, London. . Princeton University Press, Princeton. . University of Wisconsin, "Delphinus" External links The Deep Photographic Guide to the Constellations: Delphinus The clickable Delphinus Star Tales – Delphinus Warburg Institute Iconographic Database (medieval and early modern images of Delphinus) Constellations Northern constellations Constellations listed by Ptolemy Legendary mammals Constellation Articles containing	two cultures recognized Delphinus as a constellation. In Pukapuka, it was called Te Toloa and in the Tuamotus, it was called Te Uru-o-tiki. In Hindu astrology, the Delphinus corresponds to the Nakshatra, or lunar mansion, of Dhanishta. Characteristics Delphinus is bordered by Vulpecula to the north, Sagitta to the northwest, Aquila to the west and southwest, Aquarius to the southeast, Equuleus to the east and Pegasus to the east. Covering 188.5 square degrees, corresponding to 0.457% of the sky, it ranks 69th of the 88 constellations in size. The three-letter abbreviation for the constellation, as adopted by the IAU in 1922, is "Del". The official constellation boundaries, as set by Eugène Delporte in 1930, are defined by a polygon of 14 segments. In the equatorial coordinate system, the right ascension coordinates of these borders lie between and , while the declination coordinates are between and . The whole constellation is visible to observers north of latitude 69°S. Features Stars Delphinus has two stars above fourth (apparent) magnitude; its brightest star is of magnitude 3.6. The main asterism in Delphinus is Job's Coffin, nearly a 45°-apex lozenge diamond of the four brightest stars: Alpha, Beta, Gamma, and Delta Delphini. Delphinus is in a rich Milky Way star field. Alpha and Beta Delphini have 19th century names Sualocin and Rotanev, read backwards: Nicolaus Venator, the Latinized name of a Palermo Observatory director, Niccolò Cacciatore (d. 1841). Alpha Delphini is a blue-white hued main sequence star of magnitude 3.8, 241 light-years from Earth. Beta Delphini, called Rotanev. The gap between its close binary stars is visible from large amateur telescopes. To the unaided eye, it appears to be a white star of magnitude 3.6. It has a period of 27 years and is 97 light-years from Earth. Gamma Delphini is a celebrated binary star among amateur astronomers. The primary is orange-gold of magnitude 4.3; the secondary is a light yellow star of magnitude 5.1. The pair form a true binary with an estimated orbital period of over 3,000 years. 125 light-years away, the
drive can use to store onto the disk itself. The data is then passed to a chip on the circuit board that controls the access to the drive. The drive is divided into sectors of data stored onto one of the sides of one of the internal disks. An HDD with two disks internally will typically store data on all four surfaces. The hardware on the drive tells the actuator arm where it is to go for the relevant track and the compressed information is then sent down to the head which changes the physical properties, optically or magnetically for example, of each byte on the drive, thus storing the information. A file is not stored in a linear manner, rather, it is held in the best way for quickest retrieval. Rotation speed and track layout Mechanically there are two different motions occurring inside the drive. One is the rotation of the disks inside the device. The other is the side-to-side motion of the head across the disk as it moves between tracks. There are two types of disk rotation methods: constant linear velocity (used mainly in optical storage) varies the rotational speed of the optical disc depending upon the position of the head, and constant angular velocity (used in HDDs, standard FDDs, a few optical disc systems, and vinyl audio records) spins the media at one constant speed regardless of where the head is positioned. Track positioning also follows two different methods across disk storage devices. Storage devices focused on holding computer data, e.g., HDDs, FDDs, Iomega zip drives, use concentric tracks to store data. During a sequential read or write operation, after the drive accesses all the sectors in a track it repositions the head(s) to the next track. This will cause a momentary delay in the flow of data between the device and the computer. In contrast, optical audio and video discs use a single spiral track that starts at the inner most point on the disc and flows continuously to the outer edge. When reading or writing data there is no need to stop the flow of data to switch tracks. This is similar to vinyl records except vinyl records started at the outer edge and spiraled in toward the center. Interfaces The disk drive interface is the mechanism/protocol of communication between the rest of the system and the disk	heads, meaning that more tracks could be stored on each of the disks. Advancements in data compression methods permitted more information to be stored in each of the individual sectors. The drive stores data onto cylinders, heads, and sectors. The sectors unit is the smallest size of data to be stored in a hard disk drive and each file will have many sectors units assigned to it. The smallest entity in a CD is called a frame, which consists of 33 bytes and contains six complete 16-bit stereo samples (two bytes × two channels × six samples = 24 bytes). The other nine bytes consist of eight CIRC error-correction bytes and one subcode byte used for control and display. The information is sent from the computer processor to the BIOS into a chip controlling the data transfer. This is then sent out to the hard drive via a multi-wire connector. Once the data is received onto the circuit board of the drive, they are translated and compressed into a format that the individual drive can use to store onto the disk itself. The data is then passed to a chip on the circuit board that controls the access to the drive. The drive is divided into sectors of data stored onto one of the sides of one of the internal disks. An HDD with two disks internally will typically store data on all four surfaces. The hardware on the drive tells the actuator arm where it is to go for the relevant track and the compressed information is then sent down to the head which changes the physical properties, optically or magnetically for example, of each byte on the drive, thus storing the information. A file is not stored in a linear manner, rather, it is held in the best way for quickest retrieval. Rotation speed and track layout Mechanically there are two different motions occurring inside the drive. One is the rotation of the disks inside the device. The other is the side-to-side motion of the head across the disk as it moves between tracks. There are two types of disk rotation methods: constant linear velocity (used mainly in optical storage) varies the rotational speed of the optical disc depending upon the position of the head, and constant angular velocity (used in HDDs, standard FDDs, a few optical disc systems, and vinyl audio
Andalusia, and combined the troops of Soult and Marmont. Thus combined, the French outnumbered the British, putting the British forces in a precarious position. Wellington withdrew his army and, joined with the smaller corps commanded by Rowland Hill, began to retreat to Portugal. Marshal Soult declined to attack. 1813–1814 In 1813, Wellington led a new offensive, this time against the French line of communications. He struck through the hills north of Burgos, the Tras os Montes, and switched his supply line from Portugal to Santander on Spain's north coast; this led to the French abandoning Madrid and Burgos. Continuing to outflank the French lines, Wellington caught up with and smashed the army of King Joseph Bonaparte in the Battle of Vitoria, for which he was promoted to field marshal on 21 June. He personally led a column against the French centre, while other columns commanded by Sir Thomas Graham, Rowland Hill and the Earl of Dalhousie looped around the French right and left (this battle became the subject of Beethoven's orchestral piece, the Wellington's Victory (Opus 91). The British troops broke ranks to loot the abandoned French wagons instead of pursuing the beaten foe. This gross abandonment of discipline caused an enraged Wellington to write in a famous despatch to Earl Bathurst, "We have in the service the scum of the earth as common soldiers". Although later, when his temper had cooled, he extended his comment to praise the men under his command saying that though many of the men were, "the scum of the earth; it is really wonderful that we should have made them to the fine fellows they are". After taking the small fortresses of Pamplona, Wellington invested San Sebastián but was frustrated by the obstinate French garrison, losing 693 dead and 316 captured in a failed assault and suspending the siege at the end of July. Soult's relief attempt was blocked by the Spanish Army of Galicia at San Marcial, allowing the Allies to consolidate their position and tighten the ring around the city, which fell in September after a second spirited defence. Wellington then forced Soult's demoralised and battered army into a fighting retreat into France, punctuated by battles at the Pyrenees, Bidassoa and Nivelle. Wellington invaded southern France, winning at the Nive and Orthez. Wellington's final battle against his rival Soult occurred at Toulouse, where the Allied divisions were badly mauled storming the French redoubts, losing some 4,600 men. Despite this momentary victory, news arrived of Napoleon's defeat and abdication and Soult, seeing no reason to continue the fighting, agreed on a ceasefire with Wellington, allowing Soult to evacuate the city. Hailed as the conquering hero by the British, on 3 May 1814 Wellington was made Duke of Wellington, in the county of Somerset, together with the subsidiary title of Marquess Douro, in said County. He received some recognition during his lifetime (the title of "Duque de Ciudad Rodrigo" and "Grandee of Spain") and the Spanish King Ferdinand VII allowed him to keep part of the works of art from the Royal Collection which he had recovered from the French. His equestrian portrait features prominently in the Monument to the Battle of Vitoria, in present-day Vitoria-Gasteiz. His popularity in Britain was due to his image and his appearance as well as to his military triumphs. His victory fitted well with the passion and intensity of the Romantic movement, with its emphasis on individuality. His personal style influenced the fashions on Britain at the time: his tall, lean figure and his plumed black hat and grand yet classic uniform and white trousers became very popular. In late 1814, the Prime Minister wanted him to take command in Canada and with the assignment of winning the War of 1812 against the United States. Wellesley replied that he would go to America, but he believed that he was needed more in Europe. He stated: He was appointed Ambassador to France, then took Lord Castlereagh's place as first plenipotentiary to the Congress of Vienna, where he strongly advocated allowing France to keep its place in the European balance of power. On 2 January 1815 the title of his Knighthood of the Bath was converted to Knight Grand Cross upon the expansion of that order. Hundred Days Waterloo On 26 February 1815, Napoleon escaped from Elba and returned to France. He regained control of the country by May and faced a renewed alliance against him. Wellington left Vienna for what became known as the Waterloo Campaign. He arrived in the Netherlands to take command of the British-German army and their allied Dutch, all stationed alongside the Prussian forces of Generalfeldmarschall Gebhard Leberecht von Blücher. Napoleon's strategy was to isolate the Allied and Prussian armies and annihilate each one separately before the Austrians and Russians arrived. In doing so the vast superiority in numbers of the Coalition would be greatly diminished. He would then seek the possibility of peace with Austria and Russia. The French invaded the Netherlands, with Napoleon defeating the Prussians at Ligny, and Marshal Ney engaging indecisively with Wellington at the Battle of Quatre Bras. The Prussians retreated 18 miles north to Wavre whilst Wellington's Anglo-Allied army withdrew 15 miles north to a site he had noted the previous year as favourable for a battle: the north ridge of a shallow valley on the Brussels road, just south of the small town of Waterloo. On 17 June there was torrential rain, which severely hampered movement and had a considerable effect the next day, 18 June, when the Battle of Waterloo was fought. This was the first time Wellington had encountered Napoleon; he commanded an Anglo-Dutch-German army that consisted of approximately 73,000 troops, 26,000 of whom were British. Approximately 30 percent of that 26,000 were Irish. Battle of Waterloo The Battle of Waterloo commenced with a diversionary attack on Hougoumont by a division of French soldiers. After a barrage of 80 cannons, the first French infantry attack was launched by Comte D'Erlon's I Corps. D'Erlon's troops advanced through the Allied centre, resulting in Allied troops in front of the ridge retreating in disorder through the main position. D'Erlon's corps stormed the most fortified Allied position, La Haye Sainte, but failed to take it. An Allied division under Thomas Picton met the remainder of D'Erlon's corps head to head, engaging them in an infantry duel in which Picton fell. During this struggle Lord Uxbridge launched two of his cavalry brigades at the enemy, catching the French infantry off guard, driving them to the bottom of the slope, and capturing two French Imperial Eagles. The charge, however, over-reached itself, and the British cavalry, crushed by fresh French horsemen hurled at them by Napoleon, were driven back, suffering tremendous losses. A little before 16:00, Marshal Ney noted an apparent exodus from Wellington's centre. He mistook the movement of casualties to the rear for the beginnings of a retreat, and sought to exploit it. Ney at this time had few infantry reserves left, as most of the infantry had been committed either to the futile Hougoumont attack or to the defence of the French right. Ney therefore tried to break Wellington's centre with a cavalry charge alone. At about 16:30, the first Prussian corps arrived. Commanded by Freiherr von Bülow, IV Corps arrived as the French cavalry attack was in full spate. Bülow sent the 15th Brigade to link up with Wellington's left flank in the Frichermont–La Haie area while the brigade's horse artillery battery and additional brigade artillery deployed to its left in support. Napoleon sent Lobau's corps to intercept the rest of Bülow's IV Corps proceeding to Plancenoit. The 15th Brigade sent Lobau's corps into retreat to the Plancenoit area. Von Hiller's 16th Brigade also pushed forward with six battalions against Plancenoit. Napoleon had dispatched all eight battalions of the Young Guard to reinforce Lobau, who was now seriously pressed by the enemy. Napoleon's Young Guard counter-attacked and, after very hard fighting, secured Plancenoit, but were themselves counter-attacked and driven out. Napoleon then resorted to sending two battalions of the Middle and Old Guard into Plancenoit and after ferocious fighting they recaptured the village. The French cavalry attacked the British infantry squares many times, each at a heavy cost to the French but with few British casualties. Ney himself was displaced from his horse four times. Eventually, it became obvious, even to Ney, that cavalry alone were achieving little. Belatedly, he organised a combined-arms attack, using Bachelu's division and Tissot's regiment of Foy's division from Reille's II Corps plus those French cavalry that remained in a fit state to fight. This assault was directed along much the same route as the previous heavy cavalry attacks. Meanwhile, at approximately the same time as Ney's combined-arms assault on the centre-right of Wellington's line, Napoleon ordered Ney to capture La Haye Sainte at whatever the cost. Ney accomplished this with what was left of D'Erlon's corps soon after 18:00. Ney then moved horse artillery up towards Wellington's centre and began to attack the infantry squares at short-range with canister. This all but destroyed the 27th (Inniskilling) Regiment, and the 30th and 73rd Regiments suffered such heavy losses that they had to combine to form a viable square. Wellington's centre was now on the verge of collapse and wide open to an attack from the French. Luckily for Wellington, Pirch I's and Zieten's corps of the Prussian Army were now at hand. Zieten's corps permitted the two fresh cavalry brigades of Vivian and Vandeleur on Wellington's extreme left to be moved and posted behind the depleted centre. Pirch I Corps then proceeded to support Bülow and together they regained possession of Plancenoit, and once more the Charleroi road was swept by Prussian round shot. The value of this reinforcement is held in high regard. The French army now fiercely attacked the Coalition all along the line with the culminating point being reached when Napoleon sent forward the Imperial Guard at 19:30. The attack of the Imperial Guards was mounted by five battalions of the Middle Guard, and not by the Grenadiers or Chasseurs of the Old Guard. Marching through a hail of canister and skirmisher fire and severely outnumbered, the 3,000 or so Middle Guardsmen advanced to the west of La Haye Sainte and proceeded to separate into three distinct attack forces. One, consisting of two battalions of Grenadiers, defeated the Coalition's first line and marched on. Chassé's relatively fresh Dutch division was sent against them, and Allied artillery fired into the victorious Grenadiers' flank. This still could not stop the Guard's advance, so Chassé ordered his first brigade to charge the outnumbered French, who faltered and broke. Further to the west, 1,500 British Foot Guards under Maitland were lying down to protect themselves from the French artillery. As two battalions of Chasseurs approached, the second prong of the Imperial Guard's attack, Maitland's guardsmen rose and devastated them with point-blank volleys. The Chasseurs deployed to counter-attack but began to waver. A bayonet charge by the Foot Guards then broke them. The third prong, a fresh Chasseur battalion, now came up in support. The British guardsmen retreated with these Chasseurs in pursuit, but the latter were halted as the 52nd Light Infantry wheeled in line onto their flank and poured a devastating fire into them and then charged. Under this onslaught, they too broke. The last of the Guard retreated headlong. Mass panic ensued through the French lines as the news spread: "La Garde recule. Sauve qui peut!" ("The Guard is retreating. Every man for himself!"). Wellington then stood up in Copenhagen's stirrups, and waved his hat in the air to signal an advance of the Allied line just as the Prussians were overrunning the French positions to the east. What remained of the French army then abandoned the field in disorder. Wellington and Blücher met at the inn of La Belle Alliance, on the north–south road which bisected the battlefield, and it was agreed that the Prussians should pursue the retreating French army back to France. The Treaty of Paris was signed on 20 November 1815. After the victory, the Duke supported proposals that a medal be awarded to all British soldiers who participated in the Waterloo campaign, and on 28 June 1815 he wrote to the Duke of York suggesting: ... the expediency of giving to the non-commissioned officers and soldiers engaged in the Battle of Waterloo a medal. I am convinced it would have the best effect in the army, and if the battle should settle our concerns, they will well deserve it.The Waterloo Medal was duly authorised and distributed to all ranks in 1816. Controversy Much historical discussion has been made about Napoleon's decision to send 33,000 troops under Marshal Grouchy to intercept the Prussians, but—having defeated Blücher at Ligny on 16 June and forced the Allies to retreat in divergent directions—Napoleon may have been strategically astute in a judgement that he would have been unable to beat the combined Allied forces on one battlefield. Wellington's comparable strategic gamble was to leave 17,000 troops and artillery, mostly Dutch, away at Halle, north-west of Mont-Saint-Jean, in case of a French advance up the Mons-Hal-Brussels road. The campaign led to numerous other controversies. Issues concerning Wellington's troop dispositions prior to Napoleon's invasion of the Netherlands, whether Wellington misled or betrayed Blücher by promising, then failing, to come directly to Blücher's aid at Ligny, and credit for the victory between Wellington and the Prussians. These and other such issues concerning Blücher's, Wellington's, and Napoleon's decisions during the campaign were the subject of a strategic-level study by the Prussian political-military theorist Carl von Clausewitz, Feldzug von 1815: Strategische Uebersicht des Feldzugs von 1815, (English title: The Campaign of 1815: Strategic Overview of the Campaign.) Written c.1827, this study was Clausewitz's last such work and is widely considered to be the best example of Clausewitz's mature theories concerning such analyses. It attracted the attention of Wellington's staff, who prompted the Duke to write a published essay on the campaign (other than his immediate, official after-action report, "The Waterloo Dispatch".) This was published as the 1842 "Memorandum on the Battle of Waterloo". While Wellington disputed Clausewitz on several points, Clausewitz largely absolved Wellington of accusations levelled against him. This exchange with Clausewitz was quite famous in Britain in the 19th century, particularly in Charles Cornwallis Chesney's work the Waterloo Lectures, but was largely ignored in the 20th century due to hostilities between Britain and Germany. Politics Prime Minister Wellington entered politics again when he was appointed Master-General of the Ordnance in the Tory government of Lord Liverpool on 26 December 1818. He also became Governor of Plymouth on 9 October 1819. He was appointed Commander-in-Chief of the British Army on 22 January 1827 and Constable of the Tower of London on 5 February 1827. Along with Robert Peel, Wellington became an increasingly influential member of the Tory party, and in 1828 he resigned as Commander-in-Chief and became prime minister. During his first seven months as prime minister, he chose not to live in the official residence at 10 Downing Street, finding it too small. He moved in only because his own home, Apsley House, required extensive renovations. During this time he was largely instrumental in the foundation of King's College London. On 20 January 1829 Wellington was appointed Lord Warden of the Cinque Ports. Reform His term was marked by Roman Catholic Emancipation: the restoration of most civil rights to Roman Catholics in the United Kingdom of Great Britain and Ireland. The change was prompted by the landslide by-election win of Daniel O'Connell, an Roman Catholic Irish proponent of emancipation, who was elected despite not being legally allowed to sit in Parliament. In the House of Lords, facing stiff opposition, Wellington spoke for Catholic Emancipation, and according to some sources, gave one of the best speeches of his career. Wellington was born in Ireland and so had some understanding of the grievances of the Roman Catholic majority there; as Chief Secretary, he had given an undertaking that the remaining Penal Laws would only be enforced as "mildly" as possible. In 1811 Catholic soldiers were given freedom of worship and 18 years later the Catholic Relief Act 1829 was passed with a majority of 105. Many Tories voted against the Act, and it passed only with the help of the Whigs. Wellington had threatened to resign as prime minister if King George IV did not give Royal Assent. The Earl of Winchilsea accused the Duke of "an insidious design for the infringement of our liberties and the introduction of Popery into every department of the State". Wellington responded by immediately challenging Winchilsea to a duel. On 21 March 1829, Wellington and Winchilsea met on Battersea fields. When the time came to fire, the Duke took aim and Winchilsea kept his arm down. The Duke fired wide to the right. Accounts differ as to whether he missed on purpose, an act known in dueling as a delope. Wellington claimed he did. However, he was noted for his poor aim and reports more sympathetic to Winchilsea claimed he had aimed to kill. Winchilsea discharged his pistol into the air, a plan he and his second had almost certainly decided upon before the duel. Honour was saved and Winchilsea wrote Wellington an apology. The nickname "Iron Duke" originated from this period, when he experienced a high degree of personal and political unpopularity. Its repeated use in Freeman's Journal throughout June 1830 appears to bear reference to his resolute political will, with taints of disapproval from its Irish editors. During this time, Wellington was greeted by a hostile reaction from the crowds at the opening of the Liverpool and Manchester Railway. Wellington's government fell in 1830. In the summer and autumn of that year, a wave of riots swept the country. The Whigs had been out of power for most years since the 1770s, and saw political reform in response to the unrest as the key to their return. Wellington stuck to the Tory policy of no reform and no expansion of suffrage, and as a result, lost a vote of no confidence on 15 November 1830. The Whigs introduced the first Reform Bill while Wellington and the Tories worked to prevent its passage. The Whigs could not get the bill past its second reading in the British House of Commons, and the attempt failed. An election followed in direct response and the Whigs were returned with a landslide majority. A second Reform Act was introduced and passed in the House of Commons but was defeated in the Tory-controlled House of Lords. Another wave of near-insurrection swept the country. Wellington's residence at Apsley House was targeted by a mob of demonstrators on 27 April 1831 and again on 12 October, leaving his windows smashed. Iron shutters were installed in June 1832 to prevent further damage by crowds angry over rejection of the Reform Bill, which he strongly opposed. The Whig Government fell in 1832 and Wellington was unable to form a Tory Government partly because of a run on the Bank of England. This left King William IV no choice but to restore Earl Grey to the premiership. Eventually, the bill passed the House of Lords after the King threatened to fill that House with newly created Whig peers if it were not. Wellington was never reconciled to the change; when Parliament first met after the first election under the widened franchise, Wellington is reported to have said "I never saw so many shocking bad hats in my life". Wellington opposed the Jewish Civil Disabilities Repeal Bill, and he stated in Parliament on 1 August 1833 that England "is a Christian country and a Christian legislature, and that the effect of this measure would be to remove that peculiar character." The Bill was defeated by 104 votes to 54. Government Wellington was gradually superseded as leader of the Tories by Robert Peel, while the party evolved into the Conservatives. When the Tories were returned to power in 1834, Wellington declined to become prime minister because he thought membership in the House of Commons had become essential. The king reluctantly approved Peel, who was in Italy. Hence, Wellington acted as interim leader for three weeks in November and December 1834, taking the responsibilities of prime minister and most of the other ministries. In Peel's first cabinet (1834–1835), Wellington became foreign secretary, while in the second (1841–1846) he was a minister without portfolio and Leader of the House of Lords. Wellington was also re-appointed Commander-in-Chief of the British Army on 15 August 1842 following the resignation of Lord Hill. Wellington served as the leader of the Conservative party in the House of Lords from 1828 to 1846. Some historians have belittled him as a befuddled reactionary, but a consensus in the late 20th century depicts him as a shrewd operator who hid his cleverness behind the façade of a poorly informed old soldier. Wellington worked to transform the Lords from unstinting support of the Crown to an active player in political manoeuvring, with a commitment to the landed aristocracy. He used his London residence as a venue for intimate dinners and private consultations, together with extensive correspondence that kept him in close touch with party leaders in the Commons, and the main persona in the Lords. He gave public rhetorical support to Ultra-Tory anti-reform positions, but then deftly changed positions toward the party's centre, especially when Peel needed support from the upper house. Wellington's success was based on the 44 elected peers from Scotland and Ireland, whose election he controlled. Later life Family Wellesley was married by his brother Gerald, a clergyman, to Kitty Pakenham in St George's Church, Dublin on 10 April 1806. They had two children: Arthur was born in 1807 and Charles was born in 1808. The marriage proved unsatisfactory and the two spent years apart, while Wellesley was campaigning and afterward. Kitty grew depressed, and Wellesley pursued other sexual and romantic partners. The couple largely lived apart, with Kitty spending most of her time at their country home, Stratfield Saye House and Wellesley at their London home, Apsley House. Kitty's brother Edward Pakenham served under Wellesley throughout the Peninsular War, and Wellesley's regard for him helped to smooth his relations with Kitty, until Pakenham's death at the Battle of New Orleans in 1815. Retirement Wellington retired from political life in 1846, although he remained Commander-in-Chief, and returned briefly to the spotlight in 1848 when he helped organise a military force to protect London during that year of European revolution. The Conservative Party had split over the Repeal of the Corn Laws in 1846, with Wellington and most of the former Cabinet still supporting Peel, but most of the MPs led by Lord Derby supporting a protectionist stance. Early in 1852 Wellington, by then very deaf, gave Derby's first government its nickname by shouting "Who? Who?" as the list of inexperienced Cabinet ministers was read out in the House of Lords. He became Chief Ranger and Keeper of Hyde Park and St James's Park on 31 August 1850. He was also colonel of the 33rd Regiment of Foot from 1 February 1806 and colonel of the Grenadier Guards from 22 January 1827. Kitty died of cancer in 1831; despite their generally unhappy relations, which had led to an effective separation, Wellington was said to have been greatly saddened by her death, his one comfort being that after "half a lifetime together, they had come to understand each other at the end". He had found consolation for his unhappy marriage in his warm friendship with the diarist Harriet Arbuthnot, wife of his colleague Charles Arbuthnot. Harriet's death in the cholera epidemic of 1834 was almost as great a blow to Wellington as it was to her husband. The two widowers spent their last years together at Apsley House. Death and funeral Wellington died at Walmer Castle in Kent, his residence as Lord Warden of the Cinque Ports and reputedly his favourite home, on 14 September 1852. He was found to be unwell on that morning and was helped from his campaign bed, which he had used throughout his military career, and seated in his chair where he died. His death was recorded as being due to the after-effects of a stroke culminating in a series of seizures. He was aged 83. Although in life he hated travelling by rail, having witnessed the death of William Huskisson, one of the first railway accident casualties, his body was taken by train to London, where he was given a state funeral – one of a small number of British subjects to be so honoured (other examples include Lord Nelson and Sir Winston Churchill). The funeral took place on 18 November 1852. Before the funeral, the Duke's body lay in state at the Royal Hospital Chelsea. Members of the royal family, including Queen Victoria, the Prince Consort, the Prince of Wales, and the Princess Royal, visited to pay their respects. When viewing opened to the public, crowds thronged to visit and several people were killed in the crush. At his funeral there was little space to stand due to the number of attendees, and the praise given him in Tennyson's "Ode on the Death of the Duke of Wellington" attests to his reputation at the time of his death. He was buried in a sarcophagus of luxulyanite in St Paul's Cathedral next to Lord Nelson. A bronze memorial was sculpted by Alfred Stevens, and features two intricate supports: "Truth tearing the tongue out of the mouth of False-hood", and "Valour trampling Cowardice underfoot". Stevens did not live to see it placed in its home under one of the arches of the cathedral. Wellington's casket was decorated with banners which were made for his funeral procession. Originally, there was one from Prussia, which was removed during World War I and never reinstated. In the procession, the "Great Banner" was carried by General Sir James Charles Chatterton of the 4th Dragoon Guards on the orders of Queen Victoria. Most of the book A Biographical Sketch of the Military and Political Career of the Late Duke of Wellington by Weymouth newspaper proprietor Joseph Drew is a detailed contemporary account of his death, lying in state and funeral. After his death, Irish and English newspapers disputed whether Wellington had been born an Irishman or an Englishman. In 2002, he was number 15 in the BBC's poll of the 100 Greatest Britons. Owing to its links with Wellington, as the former commanding officer and colonel of the regiment, the title "33rd (The Duke of Wellington's) Regiment" was granted to the 33rd Regiment of Foot, on 18 June 1853 (the 38th anniversary of the Battle of Waterloo) by Queen Victoria. Wellington's battle record is exemplary; he participated in some 60 battles during the course of his military career. Personality Wellington always rose early; he "couldn't bear to lie awake in bed", even if the army was not on the march. Even when he returned to civilian life after 1815, he slept in a camp bed, reflecting his lack of regard for creature comforts; it remains on display in Walmer Castle. General Miguel de Álava complained that Wellington said so often that the army would march "at daybreak" and dine on "cold meat" that he began to dread those two phrases. While on campaign, he seldom ate anything between breakfast and dinner. During the retreat to Portugal in 1811, he subsisted on "cold meat and bread", to the despair of his staff who dined with him. He was, however, renowned for the quality of the wine that he drank and served, often drinking a bottle with his dinner (not a great quantity by the standards of his day). Álava was a witness to an incident just before the Battle of Salamanca. Wellington was eating a chicken leg while observing the manoeuvres of the French army through a spyglass. He spotted an overextension in the French left flank, and realised that he could launch a successful attack there. He exclaimed "By God, that will do!" and threw the drumstick in the air. After the Battle of Toulouse, Colonel Frederick Ponsonby brought him the news of Napoleon's abdication, and Wellington broke into an impromptu flamenco dance, spinning around on his heels and clicking his fingers. Military historian Charles Dalton recorded that, after a hard-fought battle in Spain, a young officer made the comment, "I am going to dine with Wellington tonight", which was overheard by the Duke as he rode by. "Give me at least the prefix of Mr. before my name," Wellington said. "My Lord," replied the officer, "we do not speak of Mr. Caesar or Mr. Alexander, so why should I speak of Mr. Wellington?" While known for his stern countenance and iron-handed discipline, Wellington was by no means unfeeling. While he is said to have disapproved of soldiers cheering as "too nearly an expression of opinion" Wellington nevertheless cared for his men: he refused to pursue the French after the battles of Porto and Salamanca, foreseeing an inevitable cost to his army in chasing a diminished enemy through rough terrain. The only time that he ever showed grief in public was after the storming of Badajoz: he cried at the sight of the British dead in the breaches. In this context, his famous despatch after the Battle of Vitoria, calling them the "scum of the earth" can be seen to be fuelled as much by disappointment at their breaking ranks as by anger. He shed tears after Waterloo on presentation of the list of British fallen by Dr John Hume. Later with his family, unwilling to be congratulated for his victory, he broke down in tears, his fighting spirit diminished by the high cost of the battle and	the official residence at 10 Downing Street, finding it too small. He moved in only because his own home, Apsley House, required extensive renovations. During this time he was largely instrumental in the foundation of King's College London. On 20 January 1829 Wellington was appointed Lord Warden of the Cinque Ports. Reform His term was marked by Roman Catholic Emancipation: the restoration of most civil rights to Roman Catholics in the United Kingdom of Great Britain and Ireland. The change was prompted by the landslide by-election win of Daniel O'Connell, an Roman Catholic Irish proponent of emancipation, who was elected despite not being legally allowed to sit in Parliament. In the House of Lords, facing stiff opposition, Wellington spoke for Catholic Emancipation, and according to some sources, gave one of the best speeches of his career. Wellington was born in Ireland and so had some understanding of the grievances of the Roman Catholic majority there; as Chief Secretary, he had given an undertaking that the remaining Penal Laws would only be enforced as "mildly" as possible. In 1811 Catholic soldiers were given freedom of worship and 18 years later the Catholic Relief Act 1829 was passed with a majority of 105. Many Tories voted against the Act, and it passed only with the help of the Whigs. Wellington had threatened to resign as prime minister if King George IV did not give Royal Assent. The Earl of Winchilsea accused the Duke of "an insidious design for the infringement of our liberties and the introduction of Popery into every department of the State". Wellington responded by immediately challenging Winchilsea to a duel. On 21 March 1829, Wellington and Winchilsea met on Battersea fields. When the time came to fire, the Duke took aim and Winchilsea kept his arm down. The Duke fired wide to the right. Accounts differ as to whether he missed on purpose, an act known in dueling as a delope. Wellington claimed he did. However, he was noted for his poor aim and reports more sympathetic to Winchilsea claimed he had aimed to kill. Winchilsea discharged his pistol into the air, a plan he and his second had almost certainly decided upon before the duel. Honour was saved and Winchilsea wrote Wellington an apology. The nickname "Iron Duke" originated from this period, when he experienced a high degree of personal and political unpopularity. Its repeated use in Freeman's Journal throughout June 1830 appears to bear reference to his resolute political will, with taints of disapproval from its Irish editors. During this time, Wellington was greeted by a hostile reaction from the crowds at the opening of the Liverpool and Manchester Railway. Wellington's government fell in 1830. In the summer and autumn of that year, a wave of riots swept the country. The Whigs had been out of power for most years since the 1770s, and saw political reform in response to the unrest as the key to their return. Wellington stuck to the Tory policy of no reform and no expansion of suffrage, and as a result, lost a vote of no confidence on 15 November 1830. The Whigs introduced the first Reform Bill while Wellington and the Tories worked to prevent its passage. The Whigs could not get the bill past its second reading in the British House of Commons, and the attempt failed. An election followed in direct response and the Whigs were returned with a landslide majority. A second Reform Act was introduced and passed in the House of Commons but was defeated in the Tory-controlled House of Lords. Another wave of near-insurrection swept the country. Wellington's residence at Apsley House was targeted by a mob of demonstrators on 27 April 1831 and again on 12 October, leaving his windows smashed. Iron shutters were installed in June 1832 to prevent further damage by crowds angry over rejection of the Reform Bill, which he strongly opposed. The Whig Government fell in 1832 and Wellington was unable to form a Tory Government partly because of a run on the Bank of England. This left King William IV no choice but to restore Earl Grey to the premiership. Eventually, the bill passed the House of Lords after the King threatened to fill that House with newly created Whig peers if it were not. Wellington was never reconciled to the change; when Parliament first met after the first election under the widened franchise, Wellington is reported to have said "I never saw so many shocking bad hats in my life". Wellington opposed the Jewish Civil Disabilities Repeal Bill, and he stated in Parliament on 1 August 1833 that England "is a Christian country and a Christian legislature, and that the effect of this measure would be to remove that peculiar character." The Bill was defeated by 104 votes to 54. Government Wellington was gradually superseded as leader of the Tories by Robert Peel, while the party evolved into the Conservatives. When the Tories were returned to power in 1834, Wellington declined to become prime minister because he thought membership in the House of Commons had become essential. The king reluctantly approved Peel, who was in Italy. Hence, Wellington acted as interim leader for three weeks in November and December 1834, taking the responsibilities of prime minister and most of the other ministries. In Peel's first cabinet (1834–1835), Wellington became foreign secretary, while in the second (1841–1846) he was a minister without portfolio and Leader of the House of Lords. Wellington was also re-appointed Commander-in-Chief of the British Army on 15 August 1842 following the resignation of Lord Hill. Wellington served as the leader of the Conservative party in the House of Lords from 1828 to 1846. Some historians have belittled him as a befuddled reactionary, but a consensus in the late 20th century depicts him as a shrewd operator who hid his cleverness behind the façade of a poorly informed old soldier. Wellington worked to transform the Lords from unstinting support of the Crown to an active player in political manoeuvring, with a commitment to the landed aristocracy. He used his London residence as a venue for intimate dinners and private consultations, together with extensive correspondence that kept him in close touch with party leaders in the Commons, and the main persona in the Lords. He gave public rhetorical support to Ultra-Tory anti-reform positions, but then deftly changed positions toward the party's centre, especially when Peel needed support from the upper house. Wellington's success was based on the 44 elected peers from Scotland and Ireland, whose election he controlled. Later life Family Wellesley was married by his brother Gerald, a clergyman, to Kitty Pakenham in St George's Church, Dublin on 10 April 1806. They had two children: Arthur was born in 1807 and Charles was born in 1808. The marriage proved unsatisfactory and the two spent years apart, while Wellesley was campaigning and afterward. Kitty grew depressed, and Wellesley pursued other sexual and romantic partners. The couple largely lived apart, with Kitty spending most of her time at their country home, Stratfield Saye House and Wellesley at their London home, Apsley House. Kitty's brother Edward Pakenham served under Wellesley throughout the Peninsular War, and Wellesley's regard for him helped to smooth his relations with Kitty, until Pakenham's death at the Battle of New Orleans in 1815. Retirement Wellington retired from political life in 1846, although he remained Commander-in-Chief, and returned briefly to the spotlight in 1848 when he helped organise a military force to protect London during that year of European revolution. The Conservative Party had split over the Repeal of the Corn Laws in 1846, with Wellington and most of the former Cabinet still supporting Peel, but most of the MPs led by Lord Derby supporting a protectionist stance. Early in 1852 Wellington, by then very deaf, gave Derby's first government its nickname by shouting "Who? Who?" as the list of inexperienced Cabinet ministers was read out in the House of Lords. He became Chief Ranger and Keeper of Hyde Park and St James's Park on 31 August 1850. He was also colonel of the 33rd Regiment of Foot from 1 February 1806 and colonel of the Grenadier Guards from 22 January 1827. Kitty died of cancer in 1831; despite their generally unhappy relations, which had led to an effective separation, Wellington was said to have been greatly saddened by her death, his one comfort being that after "half a lifetime together, they had come to understand each other at the end". He had found consolation for his unhappy marriage in his warm friendship with the diarist Harriet Arbuthnot, wife of his colleague Charles Arbuthnot. Harriet's death in the cholera epidemic of 1834 was almost as great a blow to Wellington as it was to her husband. The two widowers spent their last years together at Apsley House. Death and funeral Wellington died at Walmer Castle in Kent, his residence as Lord Warden of the Cinque Ports and reputedly his favourite home, on 14 September 1852. He was found to be unwell on that morning and was helped from his campaign bed, which he had used throughout his military career, and seated in his chair where he died. His death was recorded as being due to the after-effects of a stroke culminating in a series of seizures. He was aged 83. Although in life he hated travelling by rail, having witnessed the death of William Huskisson, one of the first railway accident casualties, his body was taken by train to London, where he was given a state funeral – one of a small number of British subjects to be so honoured (other examples include Lord Nelson and Sir Winston Churchill). The funeral took place on 18 November 1852. Before the funeral, the Duke's body lay in state at the Royal Hospital Chelsea. Members of the royal family, including Queen Victoria, the Prince Consort, the Prince of Wales, and the Princess Royal, visited to pay their respects. When viewing opened to the public, crowds thronged to visit and several people were killed in the crush. At his funeral there was little space to stand due to the number of attendees, and the praise given him in Tennyson's "Ode on the Death of the Duke of Wellington" attests to his reputation at the time of his death. He was buried in a sarcophagus of luxulyanite in St Paul's Cathedral next to Lord Nelson. A bronze memorial was sculpted by Alfred Stevens, and features two intricate supports: "Truth tearing the tongue out of the mouth of False-hood", and "Valour trampling Cowardice underfoot". Stevens did not live to see it placed in its home under one of the arches of the cathedral. Wellington's casket was decorated with banners which were made for his funeral procession. Originally, there was one from Prussia, which was removed during World War I and never reinstated. In the procession, the "Great Banner" was carried by General Sir James Charles Chatterton of the 4th Dragoon Guards on the orders of Queen Victoria. Most of the book A Biographical Sketch of the Military and Political Career of the Late Duke of Wellington by Weymouth newspaper proprietor Joseph Drew is a detailed contemporary account of his death, lying in state and funeral. After his death, Irish and English newspapers disputed whether Wellington had been born an Irishman or an Englishman. In 2002, he was number 15 in the BBC's poll of the 100 Greatest Britons. Owing to its links with Wellington, as the former commanding officer and colonel of the regiment, the title "33rd (The Duke of Wellington's) Regiment" was granted to the 33rd Regiment of Foot, on 18 June 1853 (the 38th anniversary of the Battle of Waterloo) by Queen Victoria. Wellington's battle record is exemplary; he participated in some 60 battles during the course of his military career. Personality Wellington always rose early; he "couldn't bear to lie awake in bed", even if the army was not on the march. Even when he returned to civilian life after 1815, he slept in a camp bed, reflecting his lack of regard for creature comforts; it remains on display in Walmer Castle. General Miguel de Álava complained that Wellington said so often that the army would march "at daybreak" and dine on "cold meat" that he began to dread those two phrases. While on campaign, he seldom ate anything between breakfast and dinner. During the retreat to Portugal in 1811, he subsisted on "cold meat and bread", to the despair of his staff who dined with him. He was, however, renowned for the quality of the wine that he drank and served, often drinking a bottle with his dinner (not a great quantity by the standards of his day). Álava was a witness to an incident just before the Battle of Salamanca. Wellington was eating a chicken leg while observing the manoeuvres of the French army through a spyglass. He spotted an overextension in the French left flank, and realised that he could launch a successful attack there. He exclaimed "By God, that will do!" and threw the drumstick in the air. After the Battle of Toulouse, Colonel Frederick Ponsonby brought him the news of Napoleon's abdication, and Wellington broke into an impromptu flamenco dance, spinning around on his heels and clicking his fingers. Military historian Charles Dalton recorded that, after a hard-fought battle in Spain, a young officer made the comment, "I am going to dine with Wellington tonight", which was overheard by the Duke as he rode by. "Give me at least the prefix of Mr. before my name," Wellington said. "My Lord," replied the officer, "we do not speak of Mr. Caesar or Mr. Alexander, so why should I speak of Mr. Wellington?" While known for his stern countenance and iron-handed discipline, Wellington was by no means unfeeling. While he is said to have disapproved of soldiers cheering as "too nearly an expression of opinion" Wellington nevertheless cared for his men: he refused to pursue the French after the battles of Porto and Salamanca, foreseeing an inevitable cost to his army in chasing a diminished enemy through rough terrain. The only time that he ever showed grief in public was after the storming of Badajoz: he cried at the sight of the British dead in the breaches. In this context, his famous despatch after the Battle of Vitoria, calling them the "scum of the earth" can be seen to be fuelled as much by disappointment at their breaking ranks as by anger. He shed tears after Waterloo on presentation of the list of British fallen by Dr John Hume. Later with his family, unwilling to be congratulated for his victory, he broke down in tears, his fighting spirit diminished by the high cost of the battle and great personal loss. Wellington's soldier servant, a gruff German called Beckerman, and his long-serving valet, James Kendall, who served him for 25 years and was with him when he died, were both devoted to him. (A story that he never spoke to his servants and preferred instead to write his orders on a note pad on his dressing table in fact probably refers to his son, the 2nd Duke. It was recorded by the 3rd Duke's niece, Viva Seton Montgomerie (1879–1959), as being an anecdote she heard from an old retainer, Charles Holman who was said greatly to resemble Napoleon. Holman is recorded as a servant of the Dukes of Wellington from 1871 to 1905). Following an incident when, as Master-General of the Ordnance he had been close to a large explosion, Wellington began to experience deafness and other ear-related problems. In 1822, he had an operation to improve the hearing of the left ear. The result, however, was that he became permanently deaf on that side. It is claimed that he was "never quite well afterwards". Perhaps because of his unhappy marriage, Wellington came to enjoy the company of a variety of intellectual and attractive women and had many amorous liaisons, particularly after the Battle of Waterloo and his subsequent ambassadorial position in Paris. In the days following Waterloo he had an affair with the notorious Lady Caroline Lamb, sister of one of his severely wounded officers and favourites, Col Frederick Ponsonby. He corresponded for many years with Lady Georgiana Lennox, later Lady de Ros, 26 years his junior and daughter of the Duchess of Richmond (who held the famous ball on the eve of Waterloo) and, though there are hints, it has not been clearly determined if the relationship was ever sexual. The British press lampooned the amorous side of the national hero. In 1824, one liaison came back to haunt him, when Wellington received a letter from a publisher, John Joseph Stockdale offering to refrain from issuing an edition of the rather racy memoirs of one of his mistresses Harriette Wilson, in exchange for money. It is said that the Duke promptly returned the letter, after scrawling across it, "Publish and be damned". However, Hibbert notes in his biography that the letter can be found among the Duke's papers, with nothing written on it. It is certain that Wellington reply, and the tone of a further letter from the publisher, quoted by Longford, suggests that he had refused in the strongest language to submit to blackmail. He was also a remarkably practical man who spoke concisely. In 1851, it was discovered that there were a great many sparrows flying about in the Crystal Palace just before the Great Exhibition was to open. His advice to Queen Victoria was "Sparrowhawks, ma'am". Wellington has often been portrayed as a defensive general, even though many, perhaps most, of his battles were offensive (Argaum, Assaye, Oporto, Salamanca, Vitoria, Toulouse). However, for most of the Peninsular War, where he earned his fame, his army lacked the numbers for a strategically offensive posture. Titles and tributes Nicknames The Iron Duke This commonly used nickname originally related to his consistent political resolve rather than to any particular incident. In various cases its editorial use appears to be disparaging. It is likely that its use became more widespread after an incident in 1832 in which he installed metal shutters to prevent rioters breaking windows at Apsley House. The term may have been made increasingly popular by Punch cartoons published in 1844–45. Other nicknames In the popular ballads of the day Wellington was called "Nosey" or "Old Nosey". Tsar Alexander I of Russia called Wellington "Le vainqueur du vainqueur du monde", the conqueror of the world's conqueror, the phrase "the world's conqueror" referring to Napoleon. Lord Tennyson uses a similar reference in his "Ode on the Death of the Duke of Wellington", referring to him as "the great World-victor's victor". Officers under his command called him "The Beau", as he was a fine dresser. Spanish troops called him "The Eagle", while Portuguese troops called him "Douro Douro" after his river crossing at Oporto in 1809. "Beau Douro"; Wellington found this amusing when hearing it used by a Colonel of the Coldstream Guards. "Sepoy General"; Napoleon used this term as an insult to Wellington's military service in India, publicly considering him an unworthy opponent. The name was used in the French newspaper Le Moniteur Universel, as a means of propaganda. "The Beef"; It is a theory that the Beef Wellington dish is a reference to Wellington, although some chefs dispute this. "Europe's Liberator" "Saviour of the Nations" See also Military career of Arthur Wellesley, 1st Duke of Wellington Army Gold Medal Military General Service Medal Seringapatam medal Cotiote War Notes References This on-line text contains Clausewitz's 58-chapter study of the Campaign of 1815 and Wellington's lengthy 1842 essay written in response to Clausewitz, as well as supporting documents and essays by the editors. Davies, Huw J. (2012). Wellington's Wars: The Making of a Military Genius. London: Yale University Press. . Weller, Jac (1993) [1st pub. 1972]. Wellington in India. London: Greenhill Books. . Further reading Goldsmith, Thomas. "The Duke of Wellington and British Foreign Policy 1814-1830." (PhD Diss. University of East Anglia, 2016). online Lambert, A. "Politics, administration and decision-making: Wellington and the navy, 1828–30" Wellington Studies IV, ed. C. M. Woolgar, (Southampton, 2008), pp. 185–243. Longford, Elizabeth. Wellington: Pillar of State (1972), vol 2 of her biography; online Muir, Rory. Wellington: The Path to Victory 1769–1814 (2013) vol 1 of two-volume scholarly biography excerpt and text search
capacity was available even without the command interpreter, by using BASIC extended commands. Disc Filing System (DFS) This was an optional component for the Acorn BBC Micro, offered as a kit with a disk controller chip, a ROM chip, and a handful of logic chips, to be installed inside the computer Advanced Disc Filing System (ADFS) was a successor to Acorn's DFS. AMSDOS for the Amstrad CPC computers. GDOS and G+DOS, for the +D and DISCiPLE disk interfaces for the ZX Spectrum. Disk operating systems that were the main OSs Some disk operating systems were the operating systems for the entire computer system. The Burroughs Master Control Program (MCP) for the B5000 originally ran from a drum, but starting with the B5500 it ran from a disk. It is the basis for the MCP on the B6500, B7500 and their successor systems. The SIPROS, Chippewa Operating System (COS), SCOPE, MACE and KRONOS operating systems on the Control Data Corporation (CDC) 6000 series and 7600 were all disk operating systems. KRONOS evolved into NOS and SCOPE evolved into NOS/BE. The GECOS operating system for the GE 600 family of mainframe computers (it later became GCOS). The IBM Basic Operating System/360 (BOS/360), Disk Operating System/360 (DOS/360) and Operating System/360 (OS/360) were standard for all but the smallest System/360 installations. BOS is gone, DOS has evolved into z/VSE and OS has evolved into z/OS. The DOS-11 operating system for DEC PDP-11 minicomputers. CP/M was a disk operating system--even though it was not named as such--used as the main or alternate operating system for numerous microcomputers of the 1970s and 1980s. TRSDOS was the operating system for the TRS-80 line of computers from Tandy. MS-DOS for IBM PC compatibles with Intel x86 CPUs. It started as 86-DOS, which was modeled on CP/M, and then itself served as the basis for Microsoft's MS-DOS, and was rebranded by IBM as IBM PC DOS until 1993. Various compatible systems were later produced by different organizations, starting with DR-DOS in	provide a file system for organizing, reading, and writing files on the storage disk. Strictly speaking, this definition does not apply to current generations of operating systems, such as versions of Microsoft Windows in use, and is more appropriately used only for older generations of operating systems. Disk operating systems were available for mainframes, minicomputers, microprocessors and home computers and were usually loaded from the disks themselves as part of the boot process. History In the early days of computers, there were no disk drives, floppy disks or modern flash storage devices. Early storage devices such as delay lines, core memories, punched cards, punched tape, magnetic tape, and magnetic drums were used instead. And in the early days of microcomputers and home computers, paper tape or audio cassette tape (see Kansas City standard) or nothing were used instead. In the latter case, program and data entry was done at front panel switches directly into memory or through a computer terminal / keyboard, sometimes controlled by a BASIC interpreter in ROM; when power was turned off any information was lost. In the early 1960s, as disk drives became larger and more affordable, various mainframe and minicomputer vendors began introducing disk operating systems and modifying existing operating systems to exploit disks. Both hard disks and floppy disk drives require software to manage rapid access to block storage of sequential and other data. For most microcomputers, a disk drive of any kind was an optional peripheral; systems could be used with a tape drive or booted without a storage device at all.
Acronyms and other uses Dual (brand), a manufacturer of Hifi equipment DUAL (cognitive architecture), an artificial intelligence design model DUAL algorithm, or diffusing update algorithm, used to update Internet protocol routing tables Dual language, alternative spelling of the Australian Aboriginal Dhuwal language DUAL table, a special one-row and one-column database table Dual-Ghia, US-brand of luxury-car of the late 1950s Media Dual (2008 film), a 2008 western drama film Dual (upcoming film), upcoming (2021) science fiction thriller film "Dual" (Heroes), an episode of Heroes Dual! Parallel Trouble Adventure, an anime series Dual (album), an album of traditional Scottish and Irish music recorded by Éamonn Doorley, Muireann Nic Amhlaoibh, Julie Fowlis and Ross Martin, released 2008 Dual (EP),	manufacturer of Hifi equipment DUAL (cognitive architecture), an artificial intelligence design model DUAL algorithm, or diffusing update algorithm, used to update Internet protocol routing tables Dual language, alternative spelling of the Australian Aboriginal Dhuwal language DUAL table, a special one-row and one-column database table Dual-Ghia, US-brand of luxury-car of the late 1950s Media Dual (2008 film), a 2008 western drama film Dual (upcoming film), upcoming (2021) science fiction thriller film "Dual" (Heroes), an episode of Heroes Dual! Parallel Trouble Adventure, an anime series Dual (album), an
"doubletalk", also referring to deliberately ambiguous speech, did exist at the time Orwell wrote his book, but the usage of "doublespeak", as well as of "doubletalk", in the sense emphasizing ambiguity clearly postdates the publication of Nineteen Eighty-Four. Parallels have also been drawn between doublespeak and Orwell's classic essay Politics and the English Language, which discusses the distortion of language for political purposes. In it he observes that political language serves to distort and obfuscate reality. Orwell's description of political speech is extremely similar to the contemporary definition of doublespeak: The writer Edward S. Herman cited what he saw as examples of doublespeak and doublethink in modern society. Herman describes in his book Beyond Hypocrisy the principal characteristics of doublespeak: Examples In politics Edward S. Herman and Noam Chomsky comment in their book Manufacturing Consent: the Political Economy of the Mass Media that Orwellian doublespeak is an important component of the manipulation of the English language in American media, through a process called dichotomization, a component of media propaganda involving "deeply embedded double standards in the reporting of news." For example, the use of state funds by the poor and financially needy is commonly referred to as "social welfare" or "handouts," which the "coddled" poor "take advantage of." These terms, however, are not as often applied to other beneficiaries of government spending such as military spending. The bellicose language used interchangeably with calls for peace towards Armenia by Azerbaijani president Aliyev after the 2020 Nagorno-Karabakh War were described as doublespeak in media. In advertising Advertisers can use doublespeak to mask their commercial intent from users, as users' defenses against advertising become more entrenched. Some are attempting to counter this technique with a number of systems offering diverse views and information to highlight the manipulative and dishonest methods that advertisers employ. According to Jacques Ellul, "the aim is not to even modify people’s ideas on a given subject, rather, it is to achieve conformity in the way that people act." He demonstrates this view by offering an example from drug advertising. Use of doublespeak in advertisements resulted in aspirin production rates rising by almost 50 percent from over 23 million pounds in 1960 to over 35 million pounds in 1970. In comedy Doublespeak, particularly when exaggerated, can be used as a device in satirical comedy and social commentary to ironically parody political or bureaucratic establishments' intent on obfuscation or prevarication. The television series Yes Minister is notable for its use of this device. Oscar Wilde was an early proponent of this device and a significant influence on Orwell. Intensify/downplay pattern This pattern was formulated by Hugh Rank and is a simple tool designed to teach some basic patterns of persuasion used in political propaganda and commercial advertising. The function of the intensify/downplay pattern is not to dictate what should be discussed but to encourage coherent thought and systematic organization. The pattern works in two ways: intensifying and downplaying. All people intensify, and this is done via repetition, association and composition. Downplaying is commonly done via omission, diversion and confusion as they communicate in words, gestures, numbers, et cetera. Individuals can better cope with organized persuasion by recognizing the common ways whereby communication is intensified or downplayed, so as to counter doublespeak. Doublespeak Award Doublespeak is often used by politicians for the advancement of their agenda. The Doublespeak Award is an "ironic tribute to public speakers who have perpetuated language that is grossly deceptive, evasive, euphemistic, confusing, or self-centered." It has been issued by the National Council of Teachers of English (NCTE) since 1974. The	gestures, numbers, et cetera. Individuals can better cope with organized persuasion by recognizing the common ways whereby communication is intensified or downplayed, so as to counter doublespeak. Doublespeak Award Doublespeak is often used by politicians for the advancement of their agenda. The Doublespeak Award is an "ironic tribute to public speakers who have perpetuated language that is grossly deceptive, evasive, euphemistic, confusing, or self-centered." It has been issued by the National Council of Teachers of English (NCTE) since 1974. The recipients of the Doublespeak Award are usually politicians, national administration or departments. An example of this is the United States Department of Defense, which won the award three times in 1991, 1993, and 2001. For the 1991 award, the United States Department of Defense "swept the first six places in the Doublespeak top ten" for using euphemisms like "servicing the target" (bombing) and "force packages" (warplanes). Among the other phrases in contention were "difficult exercise in labor relations", meaning a strike, and "meaningful downturn in aggregate output", an attempt to avoid saying the word "recession". NCTE Committee on Public Doublespeak The National Council of Teachers of English (NCTE) Committee on Public Doublespeak was formed in 1971, in the midst of the Watergate scandal. It was at a point when there was widespread skepticism about the degree of truth which characterized relationships between the public and the worlds of politics, the military, and business. NCTE passed two resolutions. One called for the Council to find means to study dishonest and inhumane uses of language and literature by advertisers, to bring offenses to public attention, and to propose classroom techniques for preparing children to cope with commercial propaganda. The other called for the Council to find means to study the relationships between language and public policy and to track, publicize, and combat semantic distortion by public officials, candidates for office, political commentators, and all others whose language is transmitted through the mass media. The two resolutions were accomplished by forming NCTE's Committee on Public Doublespeak, a body which has made significant contributions in describing the need for reform where clarity in communication has been deliberately distorted. Hugh Rank Hugh Rank helped form the Doublespeak committee in 1971 and was its first chairman. Under his editorship, the committee produced a book called Language and Public Policy (1974), with the aim of informing readers of the extensive scope of doublespeak being used to deliberately mislead and deceive the audience. He highlighted the deliberate public misuses of language and provided strategies for countering doublespeak by focusing on educating people in the English language so as to help them identify when doublespeak is being put into play. He was also the founder of the Intensify/Downplay pattern that has been widely used to identify instances of doublespeak being used. Daniel Dieterich Daniel Dieterich served as the second chairman of the Doublespeak committee after Hugh Rank in 1975. He served as editor of its second publication, Teaching about Doublespeak (1976), which carried forward the Committee's charge to inform teachers of ways of teaching students how to recognize and combat language designed to mislead and misinform. William D. Lutz William D. Lutz has served as the third chairman of the Doublespeak Committee since 1975. In 1989, both his own book Doublespeak and, under his editorship, the committee's third book, Beyond Nineteen Eighty-Four, were published. Beyond Nineteen Eighty-Four consists of 220 pages and eighteen articles contributed by long-time Committee members and others whose bodies of work have contributed to public understanding about language, as well as a bibliography of 103 sources on doublespeak. Lutz was also the former editor of the now defunct Quarterly Review of Doublespeak, which examined the use of vocabulary by public officials to obscure the underlying meaning of what they tell