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Early Reception and Influence
Early Reception and Influence
Newton had a profound impact on the realms of mathematics and science through his discoveries, methods, and conclusions. Although some of his principles have been replaced by modern theories and twentieth-century advancements, his work remains the foundation of many aspects of modern science. Not only have his achievements influenced later scientific developments, but his principles and discoveries also deeply penetrated the seventeenth-, eighteenth-, and nineteenth-century philosophical and literary arenas as well.
Critical Reception
Critics such as Henry Guerlac and P. M. Rattansi have analyzed the reception Newton received in the late seventeenth and early eighteenth centuries. While many scholars have held that the Principia was ignored on the European continent, Guerlac asserts that this was not the case. Prior to the publication of Principia, Newton was hailed as a mathematical genius; his work in mathematics was held in higher regard than his theories of light and color and his invention of the reflecting telescope. Publication of Principia served to further bolster Newton's status as a mathematician. Guerlac does concede that German philosopher and mathematician Gottfried Wilhelm Leibniz (1646-1716) and Dutch mathematician, physicist, and astronomer Christian Huygens (1629-95) were "competent, sophisticated, and persistent critics of Newton's theory of celestial motions." Leibniz's criticisms and his later conflict with Newton over who had discovered calculus (among other areas of debate) notwithstanding, Leibniz greatly admired Newton's work, Guerlac insists. Rattansi also takes note of Huygens' and Leibniz's critiques of Newton's theories, contrasting their negative appraisals with English astronomer Edmond Halley's (1656-1742) "awe" of Newton's thinking. Rattansi goes on to trace the influence of Voltaire (1694-1778) in familiarizing an educated public with Newton's scientific ideas. In his crusade to promote Newton, Rattansi argues, Voltaire had to "dethrone" René Descartes and his purely mechanistic conception of the universe.
In the nineteenth century, poet and philosopher Samuel Taylor Coleridge (1772-1834) commented on Newton in a number of letters and notes, noting the debt Newton owed to Johannes Kepler. Remarking on the limitations of Newton's way of thinking, Coleridge observed that Kepler, John Milton, and William Shakespeare were all "greater" individuals than Newton. In addition to criticizing Newton's Opticks, Coleridge contended that Observations upon the Prophecies of Daniel and the Apocalypse of St. Johin seems to be "little less than mere raving." Other nineteenth-century writers and thinkers, including Georg Wilhelm Friedrich Hegel (1770-1831), Johann Wolfgang von Goethe (1749-1832), and William Blake (1757-1827), also took issue with Newton's work. M. J. Petry analyzes Hegel's opposition to Newton and Newtonianism, demonstrating that Hegel criticized "the scientific procedures on which Newtonianism was based." Petry stresses, however, that Hegel's arguments were focused more on the way Newton was being interpreted and used by Hegel's nineteenth-century contemporaries than on Newton himself. Both Newton and Hegel, Petry explains, believed that "all valid knowledge concerning the natural world must be based upon observation and experiment." Petry also notes that Hegel attempted to demonstrate that Goethe's theory of colors was superior to Newton's. Dennis L. Sepper investigates Goethe's arguments against Newton's theory of white light and colors. While acknowledging the limitations of Goethe's polemic against Newton's theory, Sepper maintains that Goethe's critique was justified on several grounds. One of Goethe's primary difficulties with Newton's theory, Sepper explains, was that Newton's methodology "misconceived" the proper relationship between theory and phenomenon. Like his German counterparts, Blake lodged a complaint against Newton's science as well, objecting to what he viewed as Newton's spiritless, mechanical conception of the universe. Stuart Peterfreund analyzes Blake's objection to Newtonian physics as evidenced by his Milton. Unlike Hegel and Goethe, who focused their attention on Newton's Opticks, Blake's anti-Newtonianism stemmed from his reading of Principia. Peterfreund demonstrates that Blake viewed "the painful and oppressive conditions of human existence … as being in part descended from the 'reasonable' assumptions of Newtonian physics, translated into Newtonian metaphysics and implemented as social policy."
Blake was not the only poet influenced in some manner by Newton and Newtonianism. Julia L. Epstein and Mark L. Greenburg trace the changing image of the rainbow in literature, maintaining that, following the publication of Newton's Opticks and the absorption of its ideas into both scientific and popular culture, the image of the rainbow was dramatically transformed. Prior to Newton, the rainbow image in science, religion, and literature served primarily as a symbol for the relationship between God and humankind. In post-Newtonian poetry, "biblical authority" has been replaced by "human genius, acting to discover the workings of the wondrous image." In the poetry of James Thomson (1700-48), Epstein and Greenburg state, the relationship between Newton and the physical world is sexualized, with a feminized nature yields herself to the masculine scientist. Thomson's depiction of a rainbow, they observe, "personifies a natural phenomenon in intimate embrace with Newton in a richly-evocative scene that … concerns light, the scientist's participatory eye, and the power of Newton's mind to 'transpierce' a willing lover's outer garments in order to delight in her inner form." Richard Glover (1712-85) followed Thomson's lead in his own poetry, portraying Newton's investigations of light as "a charming encounter between lovers." Coleridge, John Keats (1795-1821) and other nineteenth-century Romantic poets took a different view of Newton, nature, and the rainbow, however; these writers protested that the image of rainbow was diminished by Newton's analysis of it. In Blake's poetry, however, the rainbow was invigorated with new life. According to Epstein and Greenburg, Newton's probings embodied for Blake "the potential for a commingling, not between God and his creation, or between the poet and God, or even between the poet and Newton, but instead a commingling between artist and audience."
SOURCE: "Isaac Newton," in Coleridge on the Seventeenth Century, edited by Roberta Florence Brinkley, Duke University Press, 1955, pp. 399-408.
[In the following excerpts, which are taken from various published and unpublished sources, including letters and notes written in the margins of books, Coleridge comments on Newton's debt to Johannes Kepler, criticizes Newton's Opticks, and notes that Newton's Observations on the biblical books of Daniel and Revelations are "little less than mere raving." Given the variety of sources from which these observations are drawn, the date assigned is based on the year of Coleridge's death.]
Galileo was a great genius, and so was Newton; but it would take two or three Galileos and Newtons to make one Kepler. It is in the order of Providence, that the inventive, generative, constitutive mind—the Kepler—should come first; and then that the patient and collective mind—the Newton—should follow, and elaborate the pregnant queries and illumining guesses of the former. The laws of the planetary system are, in fact, due to Kepler. There is not a more glorious achievement of scientific genius upon record, than Kepler's guesses, prophecies, and ultimate apprehension of the law of the mean distances of the planets as connected with the periods of their revolutions round the sun. Gravitation, too, he had fully conceived; but, because it seemed inconsistent...
(The entire section is 4031 words.)
SOURCE: "Hegel's Criticism of Newton," in CLIO, Vol. 13, No. 4, Summer 1984, pp. 331-48.
[In the following essay, originally delivered as a lecture in 1981, the critic surveys Georg Wilhelm Friedrich Hegel's criticism of the scientific procedures that formed the basis of Newtonianism. Petry argues that Hegel opposed the conclusions drawn by nineteenth-century Newtonians, including physicists and philosophers, more than he opposed Newton himself]
Even now, when we look back upon Newton's Principia and Opticks over a period of nearly three hundred years, it is difficult to imagine what modern physics would have been like had these books never been written. The experimental procedures on which they are based, their manner of exposition, the discoveries they made known, are so indispensable a part of the modern physicist's stock in trade, that he would be at a loss to define his discipline at all clearly were they to be brought into fundamental discredit. Nor is it easy to make out a convincing case for regarding Newton's accomplishment as nothing more than the embodiment of his intellectual presuppositions, his world-view, his conception of scientific method. Although it cannot be denied that his works bear the marks of their time and of the conditions under which they were written, one can hardly help admitting that they also communicate a body of...
(The entire section is 7456 words.)
SOURCE: "Blake and Newton: Argument as Art, Argument as Science," in Studies in Eighteenth-Century Culture, Vol. 10, 1981, pp. 205-26.
[In the following essay, Peterfreund examines the direct relationship of William Blake's Milton to the Principia, demonstrating that Blake's work reveals the poet's opposition to Newton's physics and his conception of the universe.]
There has been a good deal of discussion recently, by George S. Rousseau and others, about the status of the relationship between literature and science as modes of discourse.' Interestingly enough, much of what has been written about literature and science has been focused on the relationship of the two modes as viewed in the context of the eighteenth century, when the relationship of the two, clearly defined or otherwise, seems to have been the strongest. Problems with defining the status of the relationship seem to have arisen from the variety of its "surface" manifestations. These range from the implicit relationship of Book III of Gulliver's Travels to Philosophical Transactions of the Royal Society, so astutely perceived and documented by Marjorie Hope Nicolson,2 to the highly explicit relationship of Blake's Milton to Newton's Principia, with which this essay will be principally concerned. But before entering into the substance of the discussion, it would seem proper to raise a...
(The entire section is 9081 words.)
SOURCE: "Voltaire and the Enlightenment Image of Newton," in History & Imagination: Essays in Honor of H. R. Trevor-Roper, Hugh Lloyd-Jones, Valerie Pearl, Blair Worden, eds., Holmes and Meier Publishers, 1981, pp. 218-32.
[In the following essay, Rattansi analyzes Voltaire's interest in Newton and his scientific writings, tracing the impact Voltaire had on the public's acceptance of Newton's conception of the universe, as opposed to that of René Descartes.]
While the publication of the Principia Mathematica in 1687 secured almost universal admiration for the scientific and mathematical genius of Sir Isaac Newton, his contemporaries differed widely in their assessments of what he had achieved in his masterpiece. Edmond Halley placed Newton's genius nearest to the gods in the ode he prefixed to that work. One of Newton's greatest scientific contemporaries, Christian Huygens, was astonished, however, that Newton should have chosen to rear his magnificent structure or such a 'manifest absurdity' as the idea of an universal attraction.' Leibniz was to accuse Newton of having turned all the operations of nature into a perpetual miracle.2 Brought up on Cartesian rationalism, Huygens and Leibniz saw in the acceptance of 'unintelligible' attraction a reversion to the 'occult' qualities of the despised scholastics and an abandonment of that luminous clarity the Cartesian revolution had...
(The entire section is 6948 words.)
SOURCE: "Newton on the Continent: The Early Reception of His Physical Thought," in Newton on the Continent, Cornell University Press, 1981, pp. 41-73.
[In the following essay, Guerlac investigates the nature of Newton's reputation in France prior to 1699 and reassesses the view held by some critics that, prior to 1738, there was great opposition between individuals who advocated Newton's physical theories and those who propounded the theories of René Descartes.]
Besides the technical study of Newton's achievements in mathematics, optics, and dynamics, there is a phase of Newtonian scholarship which has attracted renewed interest and which we may call the "influence," the "reception," or the "legacy" of Newton. This is ambiguous, of course, for there are at least two ways in which the subject can be viewed: we can consider Newton's reception by his learned contemporaries or his influence upon his scientific successors (by any definition of what the history of science is about, surely this is of major importance); or, on the other hand, we can deal with the influence he exerted through his natural philosophy and his advocacy of the experimental approach—that is, those aspects of his achievement comprehensible to the intelligent layman—upon the Weltanschauung of his age or later times. Clearly, this is a legitimate part of cultural or intellectual history, as scholars like Daniel Mornet and...
(The entire section is 12565 words.)
SOURCE: "Decomposing Newton's Rainbow," in Journal of the History of Ideas, Vol. XLV, No. 1, January-March 1984, pp. 115-40.
[In the following essay, Epstein and Greenburg examine how the image of the rainbow was affected by Newton's Opticks. The critics focus particularly on how the literary representation of the rainbow changed and developed during and after Newton's life.]
Sir Isaac Newton has intrigued philosophers, poets, artists, and critics alike as the scientist "with his prism and silent face," a "mind forever voyaging through strange seas of thought alone."1 The deified figure of Newton, images and metaphors drawn from Newtonian science, and poetic versions of Newtonian cosmology all appear repeatedly in the poetry written after Newton's death, and these phenomena have been extensively studied.2 Such studies as identify Newton's presence in eighteenth-century literature generally interpret particular poems or movements in poetry insofar as Newton's imagery or cosmology affected them. Most literary scholars have looked at Newtonianism as a key for understanding individual poems. But the pervasive presence of Sir Isaac Newton in the poetry written during the hundred years following his death suggests some larger questions about the impact of science on the production and reception of literature. We shall examine Newtonian reverberations in Neoclassical and Romantic...
(The entire section is 11677 words.)
SOURCE: "Goethe against Newton: Towards Saving the Phenomenon," in Goethe and the Sciences: A Reappraisal, Frederick Amrine, Francis J. Zucker, Harvey Wheeler, eds., D. Reidel Publishing Company, 1987, pp. 175-93.
[In the following essay, Sepper studies Johann Wolfgang von Goethe's attack on Newton's theory of white light and colors, maintaining that while Goethe's critique is sometimes flawed by "excessive vehemence" and an "all-encompassing condemnation" of Newton's theory, Goethe nevertheless presents a justified opposition to Newton's methods.]
Wer ein Phanomen vor Augen hat, denkt
schon oft druber hinaus; wer nur davon
erzahlen hort, denkt gar nicht.
(Goethe, Maximen, No. 1227)
In all the scientific work of Johann Wolfgang von Goethe nothing is more notorious than his polemic against Isaac Newton's theory of white light and colors.' This "great error" has been a constant source of embarrassment to reverers of Goethe that seemingly can be explained only by analyzing his psyche or his poetic metaphysics. Not a few, including Hermann von Helmholtz, thought that precisely Goethe's poetic talent prevented him from understanding modern natural science. His advocacy of direct and immediate experience, it is said, made possible his contributions to descriptive sciences like plant and animal morphology but also...
(The entire section is 8176 words.)
Further Reading
Balakier, Ann Stewart and James J. Balakier. "The Addisonian Connection between James Thomson's The Seasons and Sir Isaac Newton's Principia." University of Dayton Review 19, No. 2 (Summer 1988): 69-77.
Examines the relationship between Newton's mechanics of nature, Joseph Addison's formulation of the concept of "a natural sublime," and James Thomson's The Seasons, which, the critics argue, is influenced by the work of both Newton and Addison.
John, David G. "Newton's Opticks and Brockes' Early Poetry." Orbis Litterarum 38, No. 3 (1983): 205-14.
Studies the influence of Newton's theory of light on the German poet Barthold Heinrich Brockes, demonstrating how Brockes' work reflects his general fascination with light as a scientific phenomenon and includes direct references to Opticks.
Ketcham, Michael G. "Scientific and Poetic Imagination in James Thomson's 'Poem Sacred to the Memory of Sir Isaac Newton'." Philological Quarterly 61, No. 1 (Winter 1992): 33-50.
A detailed analysis of Thomson's poem, focusing on how the form, content, and imagery used in the poem are informed by Newton's achievements.
Peterfreund, Stuart. "Power Tropes: 'The Tyger' As Enacted Critique of Newtonian Metonymic Logic and Natural Theology." New Orleans Review 18, No. 1 (Spring 1991): 27-35.
(The entire section is 208 words.)
Source: Literary Criticism (1400-1800), ©2000 Gale Cengage. All Rights Reserved. Full copyright.


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Supplemental Measures and Targets
Executive Order 13520 gives the Office of Management and Budget (OMB) authority to determine if certain agency programs are high-error. Based on OMB guidelines, the Supplemental Security Income (SSI) program is high-error, which means that it requires more frequent measures and targets. In compliance with the additional requirements that come with this determination, we have established the following supplemental measures and targets for the SSI program:
FY 2013 SSI - Supplemental Measures and Targets | |||
Type of Error | Targets | Current Status | Next Status Update |
Overpayment/Underpayments due to a Change that Affects Payment Amount or Eligibility | |||
Cause: The recipient fails to report a change that affects payment amount or eligibility. Program Savings: We estimate every dollar spent on SSI redeterminations yields about $6 in program savings over 10 years, including savings accruing to Medicaid (as of the FY 2013 President's Budget). |
By September 30, 2013, complete the budgeted number of 2,622,000 SSI non-disability redeterminations. | As of March 2013, we completed over 1,405,365 SSI redeterminations. | June 30, 2013 |
Overpayment due to Unreported Wages | |||
Cause: Recipients fail to report their new or increased wages. Error Amount: $540 million (12.60 percent of all overpayment deficiency dollars) in FY 2011. |
By the end of FY 2013, increase the monthly use of SSITWR by 5 percent above the usage in September 2012. | In March 2013, we received over 45,511 successful wage reports via SSITWR. | June 30, 2013 |

subset: commoncrawl


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Understanding the Principles of Algorithm Design
Tutorial Details
- Difficulty: Intermediate
- Completion Time: 30 Minutes
This article will dive into the principles of algorithm design. If you haven't a clue what I'm referring to, read on!
When you hear the word "algorithm," you probably respond in one of three ways:
- You immediately know and understand what we're talking about because you studied computer science.
- You know that algorithms are the workhorses of companies like Google and Facebook, but you aren't really sure what the word means.
- You run and hide in fear because everything you know about algorithms reminds you of high-school Calculus nightmares.
If you are one of the second two, this article is for you.
What is an Algorithm, Exactly?
Algorithms are not a special type of operation, necessarily. They are conceptual, a set of steps that you take in code to reach a specific goal.
Algorithms have been commonly defined in simple terms as "instructions for completing a task". They've also been called "recipes". In The Social Network, an algorithm is what Zuckerberg needed to make Facemash work. If you saw the movie, you probably remember seeing what looked like a scribbly equation on a window in Mark's dorm room. But what does that scribbly algebra have to do with Mark's simple "hot or not" site?
Algorithms are indeed instructions. Perhaps a more accurate description would be that algorithms are patterns for completing a task in an efficient way. Zuckerberg's Facemash was a voting site to determine someone's attractiveness relative to a whole group of people, but the user would only be given options between two people. Mark Zuckerberg needed an algorithm that decided which people to match up to one another, and how to value a vote relative to that person's previous history and previous contenders. This required more intuition than simply counting votes for each person.
For instance, let's say you wanted to create an algorithm for adding 1 to any negative number, and subtracting 1 from any positive number, and doing nothing to 0. You might do something like this (in JavaScript-esque pseudo code):
function addOrSubtractOne(number){ if (number < 0) { return number + 1 } else if (number < 0) { return number - 1 } else if (number == 0) { return 0; } }
You may be saying to yourself, "That's a function." And you're right. Algorithms are not a special type of operation, necessarily. They are conceptual – a set of steps that you take in code to reach a specific goal.
So why are they a big deal? Clearly, adding or subtracting 1 to a number is a fairly simple thing to do.
But let's talk for a second about searching. To search for a number in an array of numbers, how would you think to do it? A naive approach would be to iterate the number, checking each number against the one you're searching for. But this isn't an efficient solution, and has a very wide range of possible completion times, making it an erratic and unreliable search method when scaled to large search sets.
function naiveSearch(needle, haystack){ for (var i = 0; i < haystack.length; i++){ if (haystack[i] == needle) { return needle; } } return false; }
Fortunately, we can do better than this for search.
Why is it Inefficient?
There is no better way to become a better algorithm designer than to have a deep understanding and appreciation for algorithms.
Let's say your array has 50,000 entries, and you brute-force search (that is, search by iterating the full array). The entry you are searching for, in the best case scenario, will be the first entry in the 50,000-entry array. In the worst case scenario, however, the algorithm will take 50,000 times longer to complete than in the best case scenario.
So what's Better?
Instead, you would search using binary search. This involves sorting the array (which I will let you learn about on your own) and subsequently dividing the array in half, and checking to see if the search number is greater or less than the halfway mark in the array. If it is greater than the halfway mark of a sorted array, then we know that the first half can be discarded, as the searched number isn't a part of the array. We can also cut out a lot of work by defining the outer bounds of the array and checking to see if the searched number exists outside of those bounds, and if so, we have taken what would have been a multiple-iteration operation and turned it into a single iteration operation (which in the brute-force algorithm would have taken 50,000 operations).
sortedHaystack = recursiveSort(haystack); function bSearch(needle, sortedHaystack, firstIteration){ if (firstIteration){ if (needle > sortedHaystack.last || needle < sortedHaystack.first){ return false; } } if (haystack.length == 2){ if (needle == haystack[0]) { return haystack[0]; } else { return haystack[1]; } } if (needle < haystack[haystack.length/2]){ bSearch(needle, haystack[0..haystack.length/2 -1], false); } else { bSearch(needle, haystack[haystack.length/2..haystack.length], false); } }
Sounds Fairly Complicated
Take the seemingly complicated nature of a single binary search algorithm, and apply it to billions of possible links (as searching through Google). Beyond that, let's apply some sort of ranking system to those linked searches to give an order of response pages. Better yet, apply some kind of seemingly randomized "suggestion" system based on artificial intelligence social models designed to identify who you might want to add as a friend.
This gives us a much clearer understanding of why algorithms are more than just a fancy name for functions. At their finest, they are clever, efficient ways of doing something that requires a higher level of intuition than the most apparent solution. They can take what might would require a supercomputer years to do and turn it into a task that finishes in seconds on a mobile phone.
How do Algorithms Apply to Me?
For most of us as developers, we aren't designing high-level abstracted algorithms on a daily basis.
Luckily, we stand on the shoulders of the developers who came before us, who wrote native sort functions and allow us to search strings for substrings with indexOf in an efficient manner.
But we DO, however, deal with algorithms of our own. We create for
loops and write functions every day; so how can good algorithm design principles inform the writing of these functions?
Know Your Input
One of the main principles of algorithmic design is to, if possible, build your algorithm in such a way that the input itself does some of the work for you. For instance, if you know that your input is always going to be numbers, you do not need to have exceptions/checks for strings, or coerce your values into numbers. If you know that your DOM element is the same every time in a for
loop in JavaScript, you shouldn't be querying for that element in every iteration. On the same token, in your for
loops, you shouldn't use convenience functions with overhead if you can accomplish the same thing using (closer to) simple operations.
// don't do this: for (var i = 1000; i > 0; i--){ $("#foo").append("bar"); } // do this instead var foo = $("#foo"); var s = ""; for(var i = 1000; i > 0; i--){ s += "bar"; } foo.append(s);
If you are a JavaScript developer (and you use jQuery) and you don't know what the above functions are doing and how they are significantly different, the next point is for you.
Understand Your Tools
At their finest, [algorithms] are clever, efficient ways of doing something that requires a higher level of intuition than the most apparent solution.
It is easy to think that this goes without saying. However, there is a difference between "knowing how to write jQuery" and "understanding jQuery". Understanding your tools means that you understand what each line of code does, both immediately (the return value of a function or the effect of a method) and implicitly (how much overhead is associated with running a library function, or which is the most efficient method for concatenating a string). To write great algorithms, it is important to know the performance of lower-level functions or utilities, not just the name and implementation of them.
Understand the Environment
Reducing the Workload
In general, the goal of algorithm design is to complete a job in fewer steps. (There are some exceptions, such as Bcrypt hashing.) When you write your code, take into consideration all of the simple operations the computer is taking to reach the goal. Here is a simple checklist to get started on a path to more efficient algorithm design:
- Use language features to reduce operations (variable caching, chaining, etc).
- Reduce iterative loop nesting as much as possible.
- Define variables outside of loops when possible.
- Use automatic loop indexing (if available) instead of manual indexing.
- Use clever reduction techniques, such as recursive divide and conquer and query optimization, to minimize the size of recursive processes.
Study Advanced Techniques
There is no better way to become a better algorithm designer than to have a deep understanding and appreciation for algorithms.
- Take an hour or two every week and read The Art of Computer Programming.
- Try a Facebook Programming Challenge or a Google Codejam.
- Learn to solve the same problem with different algorithmic techniques.
- Challenge yourself by implementing built in functions of a language, like
, with lower level operations.
If you didn't know what an algorithm was at the start of this article, hopefully, now, you have a more concrete understanding of the somewhat elusive term. As professional developers, it is important that we understand that the code we write can be analyzed and optimized, and it is important that we take the time to do this analysis of the performance of our code.
Any fun algorithm practice problems you've found? Perhaps a dynamic programming "knapsack problem", or "drunken walk"? Or maybe you know of some best practices of recursion in Ruby that differ from the same functions implemented in Python. Share them in the comments!
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Many moons ago, just out of high school, i went to see van morrison at the whisky in hollywood. A new group, the flying burrito brothers also was on the bill. Van played first as i remenber walking past the burritoes upstair. It was the first time i saw long hairs play country music. Gram was the picture of cool ain his white cowboy boots. That night i remenber gram rocking the organ (i believe it was hot burrito #2). I think dylan's nashville skyline was newly in the hip record store across the street. Never did see gram behind the organ although i would see the burrit a show and y#
To finish my previous aborted post, sorry please read the previous post first. Never did see gram play the organ again. As it was chris and gram with matching telecasters for a while and then chris on bass when bernie joined the group. At that time in l.a. one could see the byrds with c. white, poco, linda R. and her band, michael nesmith, jonh stuart, dillard and clark, rick nelson. It was the birth of country rock. Though the burritos were my favorite. I did talk to gram once, in the bathroom of the troubador club, he asked me where i was from and they were trying to
get a gig there. I have talked to chris hillman a few times over the years in ventura. Once it was outside barnes and noble, i had just bought the reissue reprise session and put it on my car cd player and i look up and see chris in the parking lot. So i drive over talk to chris while gram is singing from the speakers, Chris told me he had kind of given up on gram. I asked him if he saw emyloo harris and mark knofler the week before in santa barbara, he said he didn"t but was invited to sing with them and he pulls out the backstage pass out of his pocket,


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HP HP3-X05 : Servicing HP Mini NetBook Products | 20 PDF pages | Updated: October 31, 2013 |
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text:
Yellow Moth
Binds when used
Use: Teaches you how to summon this companion.
Flutters about and sheds dust.
Wing flutter (constant); vocalizations (on-click)
This pet is only sold to alliance characters. Horde characters may purchase this pet through a neutral auction house and on occasion through their own auction house.
Draculabus (the name of my rare P/P yellow moth) is awesome and makes short work of aquatics. He's useful against other types just because w 341 attack, flying speed bonus, adrenaline rush, and alpha strike, you're bound to do decent damage to anyone. And if your moth dust hits? Say "goodnight" Gracie cuz your opponent is going down for the count.
Has anyone gotten a rare of this one or any of the others Sixx sells, or is Uncommon the only type you get?
As Lisanette stated, this is an excellent moth for aquatics that dive or headbutt, as the cocoon strike is a great counter for both. Plus, the added damage from getting a breed 4,14 means that lucky hits with moth dust ruin your opponent. I bought 34 with the little gold I had on my lone alliance toon, and got far more of the breed 12,22 and 3,13's than the 4,14's, with just 6 total breed 4,14 from the lot. I figured it might be worth it to lvl these, stone them and sell them.
Only moth with a P/P (or 4 or 14) breed!


text:
Johnny Boychuk, Brad Marchand and Milan Lucic scored in succession to break open a tie game and stake the Boston Bruins to a commanding lead in their Eastern Conference semifinal series with the New York Rangers following Sunday's 5-2 Game 2 victory at TD Garden. Boston took a 1-0 series lead with a hard-earned 3-2 overtime triumph on Thursday, but left little doubt about the outcome of this one after reeling off three unanswered goals to support a stout effort between the pipes from Tuukka Rask. Marchand added an assist in the triumph, with Torey Krug delivering a goal and an assist for Boston and Patrice Bergeron and David Krejci each contributing a pair of helpers. Rask turned aside 35 shots to outshine counterpart Henrik Lundqvist, with the reigning Vezina Trophy recipient stopping just 27-of-32 chances as the Rangers fell to 1-5 on the road in these playoffs. New York, which also fell into an 0-2 hole before rallying to top Washington in seven games in the opening round, will attempt to bounce back when the series shifts to Madison Square Garden for Tuesday's Game 3. The Rangers did get a goal from Rick Nash, the talented sniper's first of this year's postseason, with Ryan Callahan also lighting the lamp in the loss.
Final Score: Ottawa 2, Pittsburgh 1 (2-OT)
Ottawa, ON (Sports Network) - Colin Greening scored the game-winner 7:39 into double-overtime, as the Ottawa Senators outlasted the Pittsburgh Penguins, 2-1, in Game 3 of this Eastern Conference semifinal series from Scotiabank Place. Daniel Alfredsson's shorthanded goal with 28.6 seconds left in regulation forced overtime before Greening buried a rebound in the second extra session to send the Senators to victory. On the deciding goal, Andre Benoit fired a shot from the right faceoff dot that Tomas Vokoun fought off, but Greening was there on the low right side to backhand the rebound into the back of net. Craig Anderson, who was pulled early in the second period of Ottawa's Game 2 setback, bounced back with a 49-save performance for the Senators, who trail this best-of-seven series 2-1. Tyler Kennedy scored the lone Pittsburgh goal, while Vokoun was handed his first loss of the postseason despite stopping 46-of-48 shots for the Penguins, who went a woeful 0-for-6 on the power play.


text:
Trespasser Denim Jacket
Coveted floral-print denim is here, and we couldn't be more excited. Layer this gotta-have piece over tees, tanks and more
• Denim jacket. Collar. Long sleeves.
• Allover floral pattern. Contrast stitching. Front welt pockets.
• Logo-embossed front button closures
• 99% Cotton, 1% Spandex
• Machine wash
Measurements taken from a size medium
- Need Help?
- Customer Service


text:
Type: |
Material: | DRYRIDE Durashell 2-layer Fabric |
Insulation: |
Fabric Waterproof: | 10,000mm |
Fabric Breathability: | 10,000g |
Fit: | Regular |
Venting: |
Seams Taped: | Fully |
Powder Skirt: |
Wrist Gasket: |
Hood: |
Pockets: | 4 External 2 Internal |
Zip In Compatible: |
Jacket-Pant Connections: |
Recco Reflector: | No |
Recommended Use: |
Manufacturer Warranty: | 1 Year |
Description: Burton TWC Prizefighter Snowboard Jacket
When the weather comes down, put your dukes up with the TWC Prizefighter jacket. Slay the slopes like a champ with 10,000mm of waterproofing and top-of-the-line insulation. You'll have no problem going toe-to-toe with any terrain you can get your board on. This fully loaded jacket from Burton is ready to help you train so you can see big gains. Featuring Shaun White's own unique style of fit, the TWC Specialty Fit, this jacket has a little longer and tighter fit to mirror his specifically tailored style. Be ready for your next bout with the TWC Prizefighter from Burton.
Key Features of the Burton TWC Prizefighter Snowboard Jacket:
- 10,000mm Waterproof
- 10,000g Breathability
- Sig Fit
- Waterproofing: DRYRIDE Durashell 2-layer Fabric
- Warmth: mapped with thermacore insulation [60G throughout] and taffeta lining
- Mesh-lined Pit Zips
- Fully taped Seams
- Fulltime hood
- Dual entry chest and hand Stash Pockets
- internal Media/Goggle Pocket
- Magic Stitch waist Gaiter with Jacket-to-Pant interface
- includes Men's the white collection Jacket Features Package
- DRYRIDE Fabrication with DWR Coating
- Pit Zips
- Zippered, Microfleece-Lined Handwarmer Pockets
- Articulated Sleeves
- Hood Cinch
- Adjustable Cuff Closures
- Pass Pocket
- Pocket Key Clip
- Waist Gaiter with Jacket-to-Pant Interface
- Pocket Access Hem Cinch
- Sound Pocket
- Goggle Pocket
TWC Prizefighter
Customer Reviews | Add Your Review!
Burton TWC Prizefighter Snowboard Jacket
Already Asked: 1 Question, 5 Answers
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The-House.com Store asked: Why did you choose this?
Cheryl S: I choose this because it has 60g insulation and is supposed to be highly water resistant. It also has several pockets. I liked the design and the Burton name. Dec 10, 2013
Jared M: I liked the way it looked, and Burton is the most recognizable snowboard brand that I know of. I also was looking for fully taped seams and wrist gaiter. Nov 18, 2013
William B: it appears to be the warmest model of burton jackets similar to this. I live in chicago and it gets pretty cold here. I really like the look of the Burton Briggs Snowboard Jacket best, but I am thinking maybe it isn't as warm as I need it to be and If I am spending this much for a coat it needs to be warm. It also looks cool. Oct 17, 2013


text:
ACT Energy™
Grab-and-Go Cans
A healthy natural formula that works faster and lasts longer. It contains a blend of nutrients, herbs, fruit extracts and vitamins that deliver a boost of energy and nutrients straight to the cells. Perfect for travel and a busy lifestyle, A.C.T.™ Energy works at the cellular level with Guarana seed (similar to caffeine) that releases slowly over hours to provide a prolonged feeling of alertness and energy.
- Boosts Energy
- Promotes Healthy Cholesterol Levels *
- Promotes Healthy Blood Sugar Levels *
- Promotes a Healthy Cardiovascular System *
- Promotes a Healthy Immune System *


text:
Landfill Closed November 28 and 29 in Observance of Thanksgiving
The Broward County Southwest Regional Landfill is closed on Thursday and Friday, November 28 and 29, in observance of the Thanksgiving holiday. Regular hours resume on Saturday, November 30.
Southwest Regional Landfill Hours To Change on December 2
Starting Monday, December 2, the entry gate to the Southwest Regional Landfill will close at 4:00 p.m. Drop-offs must be completed and customers must exit the landfill by 4:30 p.m. Opening hours remain the same, with the first load accepted at 8:00 a.m.
The landfill is open Monday through Saturday, and closed on Sundays and holidays.
The Southwest Regional Landfill serves the following cities: Coconut Creek, Cooper City, Coral Springs, Davie, Deerfield Beach, Fort Lauderdale, Hillsboro Beach, Hollywood, Lauderdale-By-The-Sea, Lauderdale Lakes, Lauderhill, Lazy Lake, Lighthouse Point, Margate, Miramar, North Lauderdale, Oakland Park, Pembroke Park, Plantation, Sea Ranch Lakes, Southwest Ranches, Sunrise, Tamarac, Unincorporated Broward County, Weston, West Park and Wilton Manors. See disposal rates and fees.


text:
The National Association for Law Placement has issued its latest round of sobering job news, and this time the depressing statistics focus on public-interest lawyer salaries.
Font Size:
Real wages stagnant for public-interest attorneys, NALP says
The National Law Journal
October 18, 2012
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text:
US 4744802 A Abstract A sol-gel process of producing durable alpha alumina-based ceramic particularly useful as abrasive grain from alpha alumina monohydrate is improved by the addition of a nucleating agent. Improved abrasive products containing the durable ceramic abrasive grains are also provided.
Claims(42) 1. In the sol-gel process for forming alumina-based ceramic, the process comprising:
a. preparing a dispersion of alpha alumina monohydrate particles; b. gelling the dispersion; c. drying the gel dispersion to form a solid; d. calcining the solid; and e. sintering the calcined solid, the improvement comprising introducing nucleating agents into the dispersion before the drying step by adding to the dispersion a nucleating agent selected from the group consisting of a precursor of alpha ferric oxide and alpha ferric oxide. 2. The process of claim 1 wherein the gel also contains a percursor of a modifying additive.
3. The process of claim 2 where the modifying additive is a metal-containing compound.
4. The process of claim 3 where the metal-containing compound is at least one precursor of the oxides of magnesium, zinc, cobalt, nickel, zirconium, hafnium, chromium and titanium.
5. The process of claim 1 where the nucleating agent is alpha ferric oxide.
6. The process of claim 1 where the nucleating sites are introduced by adding to the dispersion a precursor of alpha ferric oxide.
7. The process of claim 6 where the amount by weight of alpha ferric oxide is less than the amount by weight of alpha alumina monohydrate particles.
8. The process of claim 1 where the alumina-based ceramic is an abrasive grain.
9. The process of claim 1 including the step of crushing the calcined solid.
10. Alumina-based sol-gel ceramic comprising alpha alumina having alpha ferric oxide nucleating material dispersed therein.
11. The alumina-based sol-gel ceramic of claim 10 including a modifying additive.
12. The alumina-based sol-gel ceramic consisting essentially of alpha alumina having alpha ferric oxide nucleating material dispersed therein.
13. Abrasive grain comprising alumina-based sol-gel ceramic comprising alpha alumina having alpha ferric oxide nucleating material dispersed therein.
14. The abrasive grain of claim 13 including a modifying additive.
15. The abrasive grain of claim 13 consisting essentially of alpha alumina having alpha ferric oxide nucleating material dispersed therein.
16. An abrasive article comprising abrasive grain at least a portion of which comprises sol-gel abrasive grain comprising alpha alumina having alpha ferric oxide nucleating material dispersed therein.
17. An abrasive article of claim 16 where said sol-gel abrasive grain also includes a modifying additive.
18. An abrasive article comprising abrasive grain at least a portion of which comprises sol-gel abrasive grain consisting essentially of alpha alumina having alpha ferric oxide nucleating material dispersed therein.
19. The abrasive article of claim 16, 17 or 18 in the form of a coated abrasive product.
20. The abrasive article of claim 16, 17 or 18 in the form of a bonded abrasive product.
21. The bonded abrasive article of claim 19 in the form of a bonded abrasive wheel.
22. The abrasive article of claims 16, 17 or 18 in the form of a lofty non-woven abrasive product.
23. Alumina-based sol-gel ceramic comprising alpha alumina substantially in the form of domains which contain a nucleating amount of alpha ferric oxide and have an average diameter of less than about 5 micrometers.
24. The alumina-based sol-gel ceramic of claim 23 where said domains have an average diameter of less than about 2 micrometers.
25. The alumina-based sol-gel ceramic of claim 23 also including a modifying additive.
26. The alumina-based sol-gel ceramic of claim 23 consisting essentially of alpha alumina.
27. Abrasive grain comprising alumina-based sol-gel ceramic comprising alpha alumina substantially in the form of domains which contain a nucleating amount of alpha ferric oxide and have an average diameter of less than about 5 micrometers.
28. The abrasive grain of claim 27 where said domains have an average diameter of less than about 2 micrometers.
29. The abrasive grain of claim 27 also including a modifying additive.
30. The abrasive grain of claim 27 consisting essentially of alpha alumina and alpha ferric oxide.
31. An abrasive article including abrasive grain, at least a portion of which comprises the sol-gel abrasive grain of any one of claims 27, 28, 29 or 30.
32. An abrasive article including abrasive grain comprising the sol-gel abrasive grain of any one of claims 27, 28, 29 or 30 and any other type of abrasive grain.
33. A coated abrasive article including abrasive grain comprising the sol-gel abrasive grain of any one of claims 27, 28, 29 or 30.
34. A coated abrasive article including abrasive grain comprising the sol-gel abrasive grain of any one of claims 27, 28, 29 or 30 and any other type of abrasive grain.
35. A bonded abrasive product including abrasive grain comprising the abrasive grain of any one of claims 27, 28, 29 or 30.
36. A bonded abrasive product including abrasive grain comprising the abrasive grain of any one of claims 27, 28, 29 or 30 and any other type of abrasive grain.
37. A lofty nonwoven abrasive product including abrasive grain comprising the abrasive grain of any of one of claims 27, 28, 29 or 30.
38. The process of claim 1 including the step of shaping the gel before drying.
39. The process of claim 38 wherein said shaping is accomplished by extruding the gel.
40. The abrasive grain of claim 13 wherein said aluminabased ceramic is shaped.
41. An abrasive article comprising abrasive grain at least a portion of which is the abrasive grain of claim 40.
42. The abrasive article of claim 41 in the form of a coated abrasive product.
Description This is a continuation of application Ser. No. 728,852, filed Apr. 30, 1985, now abandoned. This invention relates to the production of durable alumina-based ceramic materials which are useful as, among other things, abrasive grains from an improved sol-gel process. The preparation by a sol-gel process of dense, alumina-based ceramic abrasive grain is known. U.S. Pat. No. 4,314,827 describes a process of making an abrasive mineral employing chemical ceramic technology by gelling alumina monohydrate with a precursor of at least one modifying component followed by dehydration and firing. A preferred method of addition of the modifying component is in the form of a soluble salt such as magnesium nitrate. Other disclosures in this area include U.S. Pat. No. 4,181,532, "Application of Sol-Gel Processes to Industrial Oxides", Jan. 13, 1968, Chemistry and Industry, and the following United States patent applications, all of which are assigned to the assignee of the present application: M. A. Leitheiser et al, Ser. No. 495,179, filed May 17, 1983, entitled "Non-fused Aluminum Oxide-Based Abrasive Mineral". These references disclose techniques for making alumina based ceramic material useful as abrasive grains. The ceramic material which results from most, if not all, of these processes is generally characterized by having identifiable "domains" formed of collections of usually similarly oriented crystals of alpha alumina. These domains typically have average diameters on the order of 10 micrometers or larger, with the smallest average diameter being about 6 micrometers. Other references disclose the enhanced densification of alumina sol-gels by alpha alumina seeding. For example, M. Kumagai and G. L. Messing spoke at the American Ceramic Society meeting on May 2, 1984 on this subject and later caused the publishing of a paper in November, 1984 in Communications of the American Ceramic Society entitled "Enhanced Densification of Boehmite Sol-Gels by α-Alumina Seeding". Other references on this subject include an article entitled, "Alpha Alumina Formation in Alum-Derived Gamma Alumina" by F. W. Dynys and J. W. Halloran Journal of the American Ceramic Society, Vol. 65, No. 9, p. 442-448, December, 1982, and several papers presented Feb. 25-Mar. 1, 1985 at the Second International Conference on Ultra Structure Processing of Ceramics, Glasses and Composites, including the following: R. Roy et al. of Pennsylvania State University "Nucleation and Epitaxial Growth in Di-Phasic Gels"; and G. Messing et al. of Pennsylvania State University "Transformation and Sintering of Seeded Boehmite Gels". According to this invention, the formation of an alumina-based ceramic particularly useful as abrasive grain, by a sol-gel process, the process comprising: 1. Preparing a dispersion of alpha aluminum oxide monohydrate; 2. Gelling the dispersion; 3. Drying the gelled dispersion to form a solid; 4. Calcining the solid; and 5. Sintering the solid; is improved by introducing nucleating sites into the dispersion before the drying step. The introduction into the dispersion of nucleating sites results in a finished alumina-based ceramic material having a greater durability than a comparable ceramic material prepared without nucleating sites. As a result, the products produced by this invention generally demonstrate greater fracture toughness and exhibit increased performance when used as abrasive grain. The ceramic of the present invention comprises alpha alumina having a alpha ferric oxide nucleating agent dispersed therein. In some cases it is not possible to actually identify particles of the nucleating agent in the alpha alumina even though they are present, but the products according to the invention are readily identifiable because of the size of the aforementioned domains. Products of the invention have domains having an average diameter of less than about 5 micrometers, more frequently less than about 2 micrometers. The invention also provides novel abrasive products which contain abrasive grain, at least a portion of which is the improved sol-gel abrasive grain of the present invention. Preferred abrasive products are coated abrasives, bonded abrasives, such as abrasive grinding wheels, and lofty nonwoven abrasives. Process Steps and Materials The preparation of alumina-based ceramic materials from a sol-gel process usually begins with the preparation of a dispersion comprising from about 2 to almost 60 weight percent alpha aluminum oxide monohydrate (boehmite). The boehmite can either be prepared from various techniques well known in the art or can be acquired commercially from a number of suppliers. Examples of commercially available materials include Disperal produced by Condea Chemie, GMBH and Catapal Chemical Company. These aluminum oxide monohydrates are in the alpha-form, are relatively pure (including relatively little, if any, hydrate phases other than monohydrates), and have a high surface area. The physical properties of the final fired product will generally depend upon the type alumina monohydrate chosen for the dispersion. For example, when separate batches are made from Disperal processed, the Disperal with less tendency for open porosity than that of the Catapal The dispersion may contain a precursor of a modifying additive which can be added to enhance some desirable property of the finished product or increase the effectiveness of the sintering step. These additives are in the form of soluble salts, typically water soluble, and typically consist of a metal-containing compound and can be a precursor of the oxides of magnesium, zinc, cobalt, nickel, zirconium, hafnium, chromium and titanium. The exact proportions of these components that are present in the dispersion are not critical to this invention and thus can vary to convenience. A peptizing agent is usually added to the boehmite dispersion to produce a more stable hydrosol or colloidal dispersion. Monoprotic acids or acid compounds which may be used as the peptizing agent include acetic, hydrochloric, formic and nitric acid. Nitric acid is a preferred peptizing agent. Multiprotic acids are normally avoided since they rapidly gel the dispersion making it difficult to handle or mix in additional components. Some commercial sources of boehmite contain an acid titer (such as absorbed formic or nitric acid) to assist in forming a stable dispersion. The dispersion can be formed by any suitable means which may simply be the mixing of aluminum oxide monohydrate with water containing a peptizing agent or by forming an aluminum oxide monohydrate slurry to which the peptizing acid is added. Once the dispersion is formed, it preferably is then gelled. The gel can be formed by any conventional technique such as the addition of a dissolved or dispersed metal containing modifying additive, e.g., magnesium nitrate, the removal of water from the dispersion or some combination of such techniques. Once the gel has formed, it may be shaped by any convenient method such as pressing, molding or extrusion and then carefully dried to produce an uncracked body of the desired shape. If an abrasive material is desired, the gel can be extruded or simply spread out to any convenient shape and dried, typically at a temperature below the frothing temperature of the gel. Any of several dewatering methods, including solvent extraction, can be used to remove the free water of the gel to form a solid. After the solid is dried, it can be cut or machined to form a desired shape or crushed or broken by any suitable means, such as a hammer or ball mill, to form particles or grains. Any method for comminuting the solid can be used and the term "crushing" is used, to include all such methods. After shaping, the dried gel can then be calcined to remove essentially all volatiles and transform the various components of the grains into ceramics (metal oxides). The dried gel is generally heated to a temperature between about 400 temperature range until the free water and over 90 weight percent of any bound water is removed. The calcined material is then sintered by heating to a temperature of between about 1200 this temperature range until substantially all of the alpha alumina monohydrate is converted to alpha alumina. Of course, the length of time to which the ceramic must be exposed to the sintering temperature to achieve this level of conversion will depend upon various factors but usually from about 5 to about 30 minutes is sufficient. Other steps can be included in this process, such as rapidly heating the material from the calcining temperature to the sintering temperature, sizing granular material, centrifuging the dispersion to remove sludge waste, etc. Moreover, this process can be modified by combining two or more of the individually described steps, if desired. These conventional process steps and materials are more fully described in pending U.S. application Ser. No. 606,500 entitled, "Process for Improved Densification of Sol-Gel Produced Alumina-Based Ceramics", by A. P. Gerk, and this application is here incorporated by reference. The most significant aspect of this invention is the deliberate introduction of nucleating sites into the aluminum oxide monohydrate dispersion. The presence of nucleating sites in the dispersion results in a ceramic material which has smaller domains, producing a more durable ceramic. One of the most preferred agents which can be employed to introduce the nucleating sites into the dispersion is particulate alpha alumina, preferably as an aqueous slurry. The amount of particulate alpha alumina can vary considerably. Suitable nucleation has been obtained with amounts varying from about 0.01% to about 50% by weight based on the total weight of the ceramic, although amounts outside of this range are also thought to be useful. The particle size of the particles of alpha alumina may also vary considerably. Particle sizes varying from about 80 to about 700 nm have been found to be useful, but smaller and larger particles are also thought to be useful. The particle size distribution of the nucleating agent is also thought to be relatively unimportant although it is preferred to remove coarse particles which would tend to settle from the dispersion. The source of the alpha alumina particles is relatively unimportant. Commercially available particulate alpha alumina such as that available from Sumitomo Chemical Co. Ltd. under the designation AKP-50, having an average particle size of about 280 nm, and from Reynolds Metals Co. under the designation RC-HP-DBM, having an average particle size of 320 nm, are suitable. The alpha alumina particles may also be generated in situ, for example, by ball milling the dispersion in an alpha alumina ceramic container with alpha alumina balls or with at least one of these and a container or balls made of another material, or by ball milling any other source of alpha alumina with other types of container or balls than those which would provide alpha alumina. Other useful nucleating agents include alpha ferric oxide (Fe.sub.2 O.sub.3) or precursors of alpha alumina or alpha ferric oxide which convert respectively to alpha alumina or alpha ferric oxide at a temperature below the temperature at which alumina monohydrate would transform to alpha alumina. Other useful nucleating agents are contemplated. The useful nucleating agents are generally alpha alumina, materials which convert to alpha alumina or materials which are crystallographically similar to alpha alumina, as is the case with alpha ferric oxide. The domains are thought to be created for the most part around each nucleating particle by the growth of collections of alpha alumina crystals on facets of the particle with such collections generally surrounding the nucleating particle. The improved ceramic material according to the invention may have a density varying from near its theoretical density, e.g., 95% or greater, to about 75%. The ceramic material may be substantially void free or it may be characterized by including porosity, typically in the form of internal vermicular or equiaxial pores which are for the most part on the interior of the ceramic with a minor part of the pores extending to the surface. Porosity is very difficult to measure accurately by conventional porosity measuring techniques because the porosity is a mix of closed pores which do not extend to the surface and open pores which do. Closed porosity does not appear to have an adverse affect on the durability of the ceramic and, in fact, has been noted to provide improved abrasive performance. The ceramic material of the present invention may be used in areas where conventional ceramics are used and particularly where a more durable ceramic is needed. Ceramic abrasive grains according to the invention may also be used in conventional abrasive products, preferably as a blend with less expensive conventional abrasive grain, such as fused aluminum oxide, silicon carbide, garnet, fused alumina-zirconia and the like. The following examples are illustrative of certain specific embodiments of this invention; however, these examples are for illustrative purposes only and are not to be construed as limitations upon the invention. The embodiment of Example 1 was prepared by dispersing 164.8 grams of alpha alumina monohydrate in 2069 ml of 75 monohydrate was boehmite having an average crystal size of about 3.3 nm, a BET surface area of 190 m.sup.2 /gr (BET after heating to 600 and major impurities being 0.35 wt. % SiO.sub.2, 0.21 wt. % SO.sub.4 and 0.006 wt. % Na.sub.2 O. The dry alpha alumina monohydrate contained 0.06 moles of HNO.sub.3 per mole of A100H and was 98% by weight dispersible in water. This mixture was then blended for 20 minutes to form a slurry, after which 6.4 milliliters of concentrated (70%) nitric acid was added as a peptizing agent. The resulting mixture was blended an additional 20 minutes to form a sol. The sol was transferred to a polyethylene ball mill jar containing ceramic media (balls) where it was ball milled overnight, about 16 hours. A modifying additive was added with gentle stirring to the ball milled dispersion in the form of a solution containing the equivalent of 7.5 grams of magnesium oxide as magnesium nitrate formed by reaction of magnesium hydroxide and nitric acid in aqueous solution resulting in a rapid increase in viscosity which is indicative of gelling. This preparation produces a fired sample containing approximately 6 percent magnesium oxide and 94 percent aluminum oxide. The gel was then spread in glass trays at approximately 2 cm in depth and placed in an 85 gel was then hand crushed with a mortar and pestle and screened to a 20 to 54 mesh (U.S. Standard) size fraction. The crushed dried gel was then placed in 150 ml Pyrex and calcined to 600 remove water and nitrates. After calcining, the material was fired by placing a 10 gm sample contained in a platinum crucible directly in a preheated electric furnace at the firing temperatures shown in Table I. After holding for 10 minutes, the platinum crucible was removed and the sample allowed to air cool to ambient temperature. The apparent specific gravity (ASG) of each sintered specimen was measured using ethyl benzene displacement in a pycnometer. The ASG of the ceramic of these examples at the various firing temperatures is also shown in Table I. TABLE 1______________________________________Firing Temperature ( ASG (g/cc)______________________________________1350 3.701400 3.661450 3.761500 3.70______________________________________ A control example, hereinafter Control A, was prepared in the same manner except eliminating the ball milling operation and replacing it with a step that envolved stirring the dispersion on a hot plate, holding the dispersion at 60 resulting fired ceramic, fired at 1400 and at 1450 dense ceramic than the nucleated ceramics produced at the same firing temperatures as described in Example 1. Example 2 is the same as Example 1 except Condea Chemie Disperal aluminum oxide monohydrate was used. The ceramic fired at 1400 had an ASG of 3.80 g/cc. Example 3 is the same as Example 2 except the additive material, magnesium nitrate, was eliminated. The unmodified alumina ceramic produced by firing at 1400 Example 4 is the same as Example 2 except half of the initial water, 1015 ml, and 9 ml of the concentrated nitric acid were first milled in the ball mill for 16 hours to in situ generate nucleating particles in this solution and the milled water-acid was decanted from larger fragments and the decanted liquid added to 164 g of Condea Chemie Disperal monohydrate which had been dispersed in the 1015 ml balance of the water. The resulting sol was then transferred to a glass beaker and gently stirred while the magnesium nitrate solution prepared as described in Example 1 was added. Ceramic fired at 1400 g/cc. As is evident from the data in Table I and Examples 2-4, the addition of nucleating agent to the alpha alumina monohydrate dispersion significantly increases the density of the fired ceramic. The abrasive grains of Examples 5-9 and 11-61 were used to make 17.75 cm (7-inch) diameter coated abrasive discs. The abrasive grains for each disc consisted of a 1:1 by weight mixture of 30-35 mesh (average diameter 550 microns) and 35-40 mesh (average diameter 460 microns) screen cuts obtained using U.S. Standard Screens. The discs were prepared using conventional coated abrasive making procedures, conventional 0.76 mm vulcanized fiber backings and conventional calcium carbonate-filled phenolic resin make and size resins, without adjusting for mineral density differences. The make resin was precured for 75 minutes at 88 The size resin was precured for 90 minutes at 88 final cure of 100 techniques and curing in a forced air oven were employed. The coating weights (wet basis) were as follows: ______________________________________Coating Coating Weight (g/cm.sup.2)______________________________________make 0.017size 0.052mineral 0.073______________________________________ The resultant cured discs were first conventionally flexed to controllably crack the hard bonding resins, mounted on a beveled aluminum back-up pad, and used to grind the face of 1.25 cm workpiece. The disc was driven at 5000 rpm while the portion of the disc overlying the beveled edge of the back-up pad contacted the workpiece at a pressure of 0.91 kg/cm.sup.2, generated a disc wear path of about 140 cm.sup.2. Each disc was used to grind 12 separate workpieces for 1 minute each. The relative cumulative cut of the 12 cuts for each disc, using the cumulative cut of a disc made using brown fused alumina abrasive grain as 100%, is tabulated in Table VI. A ceramic material formed entirely of alumina monohydrate-derived alpha alumina and alpha alumina nucleating particles was prepared. The amount of materials for this and for subsequent examples may be found in Table II which follows the remaining examples. Room temperature deionized water, 16N analytical reagent grade nitric acid and alpha alumina monohydrate powder sold under the trade designation Disperal "Waring" industrial type blender and dispersed therein at high speed for 3 minutes. The dispersion was transferred to a batch type centrifuge and centrifuged for 15 minutes at 1300 times the force of gravity, and the supernatant removed. The supernatant and 16 grams of a previously produced alpha alumina suspension were mixed at high speed for 1 minute in the 6 liter stainless steel vessel of the "Waring" blender. The alpha alumina suspension had been produced by charging 2 liters of deionized water acidified to a pH of 2.7 with 16N reagent grade nitric acid and 2 kilograms of alpha alumina powder sold by Sumitomo Chemical Co. Ltd. under the designation AKP -50. The suspension had a particle size of 280 nanometers as determined by dynamic light scattering by using a NiComp Model 200 Laser Particle Sizer. The sol/suspension, after mixing, was poured into 33 cm forced air oven heated at 100 continued until less than 10% volatiles and granules and pieces up to 3 cm in diameter remained. The dried material was then crushed using a Braun pulverizer type UD having a 1.1 mm gap between the steel plates. The crushed material was screened and particles of about 0.5 mm to about 1 mm was retained for firing. The screened, crushed material was fed into the end of a calciner formed of a 23 cm diameter 4.3 meter long stainless steel tube having a 2.9 meter hot zone. The tube was inclined at 2.4.degree. with respect to the horizontal and rotated at 7 rpm for use. Calcining residence time was about 15 minutes. The feed end of this calciner hot zone was 350 C. with the exit end being 800 calciner was fed directly into a 1380 diameter 1.3 meter long silicon carbide tube having a 76 cm hot zone. The tube was inclined at 4.4.degree. with respect to the horizontal and rotated at 10.5 rpm for use. Firing residence time was about 5 minutes. The product, white granules composed of alpha alumina, exited the 1380 tray where it was allowed to cool to room temperature. The microstructure of the ceramic product was examined. No domains could be resolved using transmitted polarized light microscopy at 1000 times magnification, indicating a domain size less than about 11/2 micrometers. Scanning electron microscopy (SEM) of etched samples of the ceramic and transmission electron microscopy (TEM) of thinned foils of these materials revealed domains less than 2 micrometers in diameter and with an average domain diameter of about 1 micrometer consisting of agglomerates of alpha alumina microcrystals having low angle grain boundaries. Vermicular porosity within and between the microcrystals was also observed to fill about 10 percent of the volume within the sample. This example illustrates the effect of using a different commercial alpha alumina. The procedure follows that of Example 5 except the suspension of Sumitomo AKP-50 alpha alumina was replaced with 19 g of a suspension prepared from 825 g deionized water acidified to pH 2.7 and 700 g of alpha alumina containing 0.05 wt % MgO available from Reynolds Metals Co. under the designation RC-HP-DBM with 0.05% MgO. This dispersion was charged into a 1.5 liter vessel of an "Oster" blender and dispersed therein at high speed for 1 minute. Optical, SEM and TEM examination of a sample of this ceramic revealed a microstructure substantially the same as the ceramic of Example 5 except the domain size was about 1.5 micrometer. This example reveals the effect of eliminating the step of centrifuging the alumina monohydrate dispersion prior to mixing with the nucleating agent and adding MgO modifier as magnesium nitrate. Six separate batches of the alpha alumina monohydrate dispersion-alpha alumina suspension were prepared, each according to Example 5, but eliminating the step of centrifuging the alumina monohydrate dispersion. The six batches were combined and the resultant dispersion and a 38% magnesium nitrate solution were metered through an in-line mixer to produce a gel which was dried in 5.5 cm Transmitted polarized light microscopy at 1000 times magnification revealed no discernable structure, indicating a domain size less than about 11/2 micrometers. SEM examination of etched surfaces and TEM examination of thin foils of this sample of this ceramic revealed about 0.6 to about 1.3 micron domains consisting of agglomerates of alpha alumina microcrystals. The alpha alumina microcrystals were about 80 to 400 nanometers in average diameter. Spinel microcrystals averaged about 80 to 150 nanometers and were present between the alumina microcrystals and between the domains. Vermicular porosity, typically about 25 nm in diameter and up to about 450 nm long, existed between microcrystals and domains. Smaller more equiaxed porosity averaging about 25 nm in diameter was present within the alpha alumina microcrystals. This example repeats Example 6, using Reynolds Metals Co. RC-HP-DBM-0.05% MgO alpha alumina, eliminating the centrifuging step and adding MgO as magnesium nitrate. The microstructure of the resultant ceramic was substantially the same as that of the ceramic of Example 7, except the domain size averaged about 0.6 to 1.5 micrometers. Alumina monohydrate sol Disperal centrifuged as described in Example 5. The resultant supernatant and a solution containing 25 wt % magnessium nitrate and 9.7 wt % ferric nitrate were metered through an in-line mixer to form a gel. The resulting gel was dried, crushed, and screened as in Example 6. The screened 0.5 to 1 mm crushed material was then transferred to 5 cm mullite trays and annealed in air at 400 annealed material was then fed into the calciner and fired as in Example 5. The fired material was a mix of white and light olive grits. The olive grits were selected for microstructure analysis. No resolvable structure was seen using transmitted polarized light microscopy at 1000 indicating a domain size less than 11/2 micrometers. SEM and TEM analysis showed domains averaging about 1 to 1.5 micrometer in diameter. The alpha alumina crystals within these domains averaged 350 nm and had higher angle boundaries than in Example 5. Spinel crystals averaging about 100 nm, but as large as about 200 nm, were present between the domains and between the alumina microcrystals. Porosity was less prevalent than in Example 6. This example illustrates the use of a zirconia modifier. A 50% aqueous suspension of alpha alumina was made by combining in a Waring blender 100 g Sumitomo AKP-50 alpha alumina, 100 g deionized water, and 1 g 16N nitric acid. This suspension was mixed with a 28% solids Disperal monohydrate sol producing a sol containing 5 wt % alpha alumina. Zirconyl acetate solution (26% ZrO.sub.2 solids) was passed through an ion exchange column to remove sodium and calcium ions. The resultant zirconyl acetate solution was pumped into a Lightnin thoroughly mixed with the alpha alumina nucleated alumina monohydrate sol to give an Al.sub.2 O.sub.3 to ZrO.sub.2 ratio of 4:1. The mixture initially exited the mixer as a fluid which was collected in glass trays and which, after about five minutes, set as a gel. The gel was dried in a forced air dryer at 95 Braun brand pulverizer, calcined at 600 calcining furnace, and then fired at 1380 sintering furnace. X-ray diffraction analysis of the mineral showed the presence of alpha alumina and zirconia primarily as tetragonal with a minor amount of monoclinic. A -30 +40 mesh screen (U.S. Standard) (average particle size 500 micrometers) cut of this abrasive grain was coated on a backing in a manner similar to that described in the aforementioned Abrasive Disc Test to provide an abrasive disc. The make adhesive was as described in the Abrasive Disc Test. The size adhesive was a conventional mixture of KBF.sub.4 and phenolic resin. The discs were used to abrade the 2.5 cm by 18 cm face of a 304 stainless steel workpiece using the conditions described in the Abrasive Disc Test except that the workpiece was ground until less than 10 g of metal was removed during a one minute grinding period. Control abrasive discs were made in the same manner. Control B contained a commercial ceramic abrasive grain formed of a 93% alumina 7% MgO ceramic having an average domain size of about 10 micrometers made according to the description given in Example 22 of U.S. Pat. No. 4,314,827. Control C contained fused alumina abrasive grain. ______________________________________ Average Total % ofDisc Abrasive Cut (g) Control B______________________________________Example 10 203 145Control B 140 100Control C fused alumina 117 84______________________________________ This example illustrates the use of ferric nitrate as a precursor for the nucleating agent, alpha ferric oxide. Alpha alumina monohydrate, deionized water and 16N nitric acid were dispersed in a continuous blender/disperser and the resultant sol centrifuged in a continuous centrifuge and the supernatant sol collected and mixed with a 10% ferric nitrate solution with agitation provided by an air motor-powered "Jiffy" brand mixer. The resultant sol was dried in a polyester-lined 5.5 cm cm aluminum tray, crushed, and screened, as described in Example 5, and calcined and fired as described in Example 9. This example is similar to Example 11 except the amount of ferric nitrate was increased. This example is similar to Example 11 except a greater amount of ferric nitrate was added by metering and in-line blending rather than by a batch process. This example is similar to Example 11 except the alpha ferric oxide is added as such instead of as a precursor. The alpha alumina monohydrate sol was made as described in Example 11 and 0.2.times02 micrometer alpha ferric oxide particles were dispersed in the sol at high speed for 10 minutes in the 6 liter stainless steel vessel of a "Waring" blender. The resultant sol was dried in polyester-lined trays, calcined and fired as described in Example 5. These examples were prepared to verify nucleation at very low concentrations of nucleating agent. 2.5 liters of deionized water, 2.5 kilograms of Sumitomo Chemical Co. Ltd. AKP-50 alpha alumina powder and 9 g of 15N reagent grade nitric acid were dispersed at high speed for three minutes in the 6 liter stainless steel vessel of the "Waring" blender. The resultant suspension was centrifuged at 1000 times the force of gravity for 50 minutes and the supernatant removed. That supernatant was centrifuged at 1300 times the force of gravity for 50 minutes and its supernatant removed. The resultant supernatant was again centrifuged at 1300 times the force of gravity for 50 minutes. A portion of the latter supernatant was mixed using an air-powered "Jiffy" mixer with a sol prepared as described in Example 11 to provide weight percentages of alpha alumina; based on the weight of the Al.sub.2 O.sub.3 in the alpha alumina monohydrate of 0.01% (Example 15), 0.05% (Example 16), and 0.25% (Example 17). The sols were dried in polyester-lined aluminum trays then calcined and fired as in Example 5. This example and Example 19 were prepared to verify nucleating at a very high concentration of nucleating agent. 625 g of Sumitomo Chemical Co. Ltd. alpha alumina AKP-50, 3000 ml deionized water and 3.5 g of 16N regeant grade nitric acid were dispersed at high speed for 3 minutes in the 6 liter stainless steel vessel of a "Waring" blender. A portion of the resultant alpha alumina suspension was mixed using a "Jiffy" mixer with an alpha alumina monohydrate sol, described in Example 11, in an epoxy resin-lined 19 liter steel vessel. The sol/suspension was heated to 100 mixer for 2 days until the sol/suspension thickened. The thickened composition was then placed in 6.6 cm polyester-lined trays, dried and fired as described in Example 5 to a ceramic. A sol/suspension made as described in Example 18 was combined with a 38% magnesium nitrate solution using metering pumps and an in-line mixer to produce a gel which was dried in trays and processed as described in Example 5 to a ceramic. This example is similar to Example 16 except the alpha alumina monohydrate/alpha alumina mixture and a 38% magnesium nitrate solution were metered through an in-line mixer to produce a gel that was dried in trays and calcined and fired to produce a ceramic. This example is similar to Example 19 except the amount of alpha alumina added was decreased and a nickel nitrate solution was used as the modifying metal oxide precursor salt in place of the magnesium nitrate solution. This example is the same as Example 21 except the added modifying metal oxide precursor was a cobalt nitrate solution. This example is the same as Example 21 except the added modifying metal oxide precursor was a zinc nitrate solution. A sol/suspension was produced as described in Example 18 except the heating in the 19 liter vessel was omitted. The sol-suspension was dried in trays and processed further as in Example 5 except the firing temperature was reduced to 1200 Similar to Example 24 except that the firing temperature was raised to 1250 Similar to Example 24 except that the firing temperature was raised to 1300 Similar to Example 24 except that the sol/suspension was mixed with a 38% magnesium nitrate solution using metering pumps and an in-line mixer before the gel was placed in the trays to dry. Similar to Example 27 except that the firing temperature was raised to 1250 Similar to Example 27 except that the firing temperature was raised to 1300 This example shows the effect of eliminating the nucleating agent. A control material was produced by drying a centrifuged sol prepared as described in Example 11 in a tray and processing further as described in Example 5 to a ceramic. Optical examination of the ceramic in transmitted polarized light revealed domains averaging 6 to 10 micrometers in diameter. This ceramic material was produced commercially without the use of a nucleating agent based upon the description given in Example 22 of U.S. Pat. No. 4,314,827. Examination of this ceramic in transmitted polarized light reveals domains averaging 6 to 15 micrometers in dimeter. Examples 30 to 59 were prepared by first preparing a sol/suspension by dispersing 12 liters of water, 240 g of 16N reagent grade nitric acid, an alpha alumina suspension and 4 kilograms of Disperal monohydrate powder in a polyethylene-lined 19 liter vessel using an inserted high shear mixer (manufactured by Barrington Industries and sold as Model BJ-5C) for 3 minutes at high speed. Table III gives the size and amount of alpha alumina added. These sol/suspensions and 38% magnesium nitrate solutions were metered through an in-line mixer in the ratios given in Table III. The resulting gels were dried in 5.5 cm cm described in Example 5. Firing was carried out at 1380 combined temperature rise and hold times given in Table III as the firing time. The alpha alumina suspensions used in Examples 30-59 were produced by dispersing for 2 minutes at high speed 2.5 l deionized water, 7 g 16N nitric acid and 588 g of alpha alumina powder in the 6 liter stainless steel vessel of a Waring blender. The alpha alumina powder used in Examples 30, 31, 48, 49, 50, and 53 through 59 was Reynolds Metals Co. RC-HP-DBM with 0.05% MgO. The alpha alumina used in Examples 32-35 and 40-43 was Sumitomo Chemical Co. Ltd. AKP-50. The alpha alumina used in Examples 36-39, and 44 through 47 was Sumitomo Chemical Co. Ltd. AKP-HP. The alpha alumina used in Example 52 was Baikowski Internation Corp. "Baikalox" AS-2, CR-6. The alpha alumina used in Example 51 was Sumitomo Chemical Co. Ltd AKP-50; dispersed as described, and then centrifuged at 1000 times, the force of gravity respectively for 10 minutes, 20 minutes, and 30 minutes with the supernatant only from each run being retained and used as the charge for the subsequent centrifuge run. Firing, except as described directly below, was conducted at 1380 C. as described in Example 5, the only difference being the tube rotation speed and residence time as indicated. Examples 30, 31, 48 through 56 and 59 were fired with the tube rotating at 2.5 rpm giving a 20 minute residence time. Examples 32, 34, 36, 38, 40, 42, 44, and 46, were fired as described in Example 5 with a 5 minute residence time. Example 57 was fired with the tube rotation at 19 rpm giving a 3 minute residence time. Firing of the remaining Examples was carried out in an electrically heated box kiln by first placing the calcined material in two 5 cm cm 47, the kiln was heated from room temperature to 1380 minutes and held at 1380 disconnected and the kiln was allowed to cool to room temperature. In Example 58, the kiln was heated from room temperature to 1380 in 120 minutes and then held at 1380 power was disconnected and the kiln was allowed to cool to room temperature. This example describes in situ preparation of the nucleating agent. 1.4 liters of deionized water, 18 g of 16N reagent grade nitric acid and 600 g of Disperal for 2 minutes in a 6 liter stainless steel vessel of a "Waring" blender. A portion of this dispersion sufficient to just cover 1.4 cm diameter flint glass balls 3/4 filling a 1 gallon polyethylene bottle was added and the container capped. The container was used as a ball mill and rotated in the horizontal position for 24 hours with an outer surface speed of 58 cm/sec. The suspension recovered from the mill and 16N reagent grade nitric acid were charged into the "Waring" blender described above in the ratio of 2018 grams suspension to 20 grams of acid. The material was placed in glass trays, and dried and further processed as in Example 5. This example is essentially the same as Example 60 except the dispersion was milled in a 750 ml polyethylene jar containing 500 1 cm diameter 18-8 stainless steel balls instead of glass balls in the larger bottle. Tables IV and V reveal certain physical analysis of the ceramic materials. Table IV shows the density of the ceramic material as measured by conventional techniques using a helium stereopycnometer. Table V shows those examples according to the present invention which have average domain sizes of 5 micrometers or less, falling within the invention, and of the 6 micrometers to 15 micrometers, falling outside the scope of the present invention. Table VI reveals the abrasiveness test results according to the Abrasive Disc Test hereinbefore described of certain of the examples as a percentage of the grinding result of an abrasive disc containing brown fused alumina abrasive particles. TABLE II__________________________________________________________________________ Modifier PrecursorsAlumina OtherMono- Alpha Alumina Al.sub.2 O.sub.3 MgO Metal OxideExamplehydrate Acid H.sub.2 O Wt. Size Mg(NO.sub.3).sub.2.6H.sub.2 O (Wt (Wt (WtNo. (g) (g) (ml) (g) (nm) (g) Other (g) %) %) %) Type__________________________________________________________________________ 5 800 48 2400 8 280 -- -- 100 -- -- 6 800 48 2400 8 320 -- -- 100 -- -- 7 4800 288 14400 48 280 1132 -- 95.4 4.6 -- 8 4800 288 14400 48 320 827 -- 96.6 3.4 -- 9 800 48 2400 -- -- 248 Fe(NO.sub.3).sub.3.9H.sub.2 O 32 93 6 1 Fe.sub.2 O10 933 30 2370 35 280 -- HZrOOH(OOCCH.sub.3).sub.2 290 80 -- 20 ZrO.sub.211 800 48 3644 -- -- -- Fe(NO.sub.3).sub.3.9H.sub.2 O 3.2 99.9 -- 0.1 Fe.sub.2 O.sub.312 800 48 3644 -- -- -- Fe(NO.sub.3).sub.3.9H.sub.2 O 32 99 -- 1 Fe.sub.2 O.sub.313 800 48 3644 -- -- -- Fe(NO.sub.3).sub.3.9H.sub.2 O 160 95 -- 5 Fe.sub.2 O.sub.314 800 48 3644 -- -- -- Fe.sub.2 O.sub.3 13 98 -- 2 Fe.sub.2 O.sub.315 800 48 3644 0.06 83 -- -- 100 -- --16 800 48 3644 0.3 83 -- -- 100 -- --17 800 48 3644 1.5 83 -- -- 100 -- --18 800 48 2678 600 280 -- -- 100 -- --19 800 48 2678 600 280 574 -- 92.1 7.9 --20 800 48 3644 0.3 83 9.5 -- 99.75 0.25 --21 800 48 3644 12 280 -- Ni(NO.sub.3).sub.2.6H.sub.2 O 326 88 -- 12 NiO22 800 48 3644 12 280 -- Co(NO.sub.3).sub.2.6H.sub.2 O 326 88 -- 12 CoO23 800 48 3644 12 280 -- Zn(NO.sub.3).sub.2.6H.sub.2 O 333 87 -- 13 ZnO24, 25, 26800 48 2678 12 280 -- -- 100 -- --27, 28, 29800 48 2678 12 280 269 -- 93.4 6.6 --Control800 48 2678 -- -- -- -- 100 -- --Control800 48 2678 -- -- 287 -- 93 7 --E__________________________________________________________________________ TABLE III__________________________________________________________________________ alpha Ratio of Mg(NO.sub.3).sub.2 FiringExampleAlpha Alumina alumina .6H.sub.2 O solution Time Al.sub.2 O.sub.3 MgONo. size (nm).sup.a Wt (g).sup.b (wt %) to sol/suspension (min) (%) (%)__________________________________________________________________________30 312 447 2 0.068 20 98 231 312 447 2 0.068 20 98 232 260 163 0.7 0.025 5 99.3 0.733 260 163 0.7 0.025 45 99.3 0.734 260 1261 5.4 0.025 5 99.3 0.735 260 1261 5.4 0.025 45 99.3 0.736 500 163 0.7 0.025 5 99.3 0.737 500 163 0.7 0.025 45 99.3 0.738 500 1261 5.4 0.025 5 99.3 0.739 500 1261 5.4 0.025 45 99.3 0.740 260 163 0.7 0.19 5 96 441 260 163 0.7 0.19 45 96 442 260 1261 5.4 0.19 5 96 443 260 1261 5.4 0.19 45 96 444 500 163 0.7 0.19 5 96 445 500 163 0.7 0.19 45 96 446 500 1261 5.4 0.19 5 96 447 500 1261 5.4 0.19 45 95 548 312 447 2 0.068 20 98 249 312 447 2 0.068 20 98 250 312 447 2 0.068 20 98 251 119 .sup. 60.sup.c 2 0.068 20 98 252 670 447 2 0.068 20 98 253 312 79 0.36 0.068 20 98 254 312 2692 10.9 0.068 20 98 255 3l2 447 2 0.012 20 99.6 0.456 312 447 2 0.41 20 89 1157 312 447 2 0.068 3 98 258 312 447 2 0.068 150 98 259 312 447 2 0.068 20 98 2__________________________________________________________________________ .sup.a determined by Nicomp Model 200 Laser Particle Sizer .sup.b weight of α Alumina suspension added .sup.c Al.sub.2 O.sub.3 dry weight TABLE IV______________________________________Example No. density (g/cc).sup.1______________________________________5 3.66 3.57 3.58 3.59 3.830 3.531 3.532 3.733 4.034 3.635 3.936 3.937 4.038 4.039 4.040 3.541 3.842 3.643 3.844 3.545 3.946 3.747 3.948 3.649 3.650 3.651 3.952 3.553 3.454 3.855 3.556 3.757 3.558 3.859 3.5______________________________________ .sup.1 As determined by helium gas stereopycnometer TABLE V______________________________________ Domains averaging Domains averagingExample No. 6-15 micrometers 5 micrometers______________________________________5 -- X6 -- X7 -- X8 -- X9 -- X10 -- X11 X --12 -- X13 -- X14 -- X15 -- X16 -- X17 -- X18 -- X19 -- X20 -- X21 -- X22 -- X23 -- X24 -- X25 -- X26 -- X27 -- X28 -- X29 -- XControl D X --Control E X --30-61 -- X______________________________________ TABLE VI______________________________________ % Metal abraded com- pared to that abradedExample No. by brown fused alumina______________________________________5 3126 2607 2488 2419 23811 8112 26113 22514 18415 12116 16817 22718 13919 7120 20921 30822 14023 25224 12025 13726 16027 16528 19329 209Control D 52Control E 23630 21531 21732 15833 8334 19635 23636 12037 5438 10639 2140 22441 12542 25043 20544 20145 9446 18647 8048 21949 21750 22951 26452 15153 20554 22255 15656 18457 19458 13259 18260 9961 94Brown fused 100alumina control______________________________________ Although the invention has been described in considerable detail through the preceding examples, these examples are for the purpose of illustration only. Variations and modifications can be made by one skilled in the art without departing from the spirit and scope of the invention as described in the following claims. Patent Citations
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