 it is sometimes assumed, for the claim to be true (Zacharias most likely dates of birth would have made him 2-5 years old at the time) grandfather Hans Martens must have invented it.

Other claims have come forward over the years. Physicist Jean Henri van Swinden's 1822-23 investigation reached the conclusion supporting Janssen and in 1841 a collector named Zacharias Snijder came forward with 4 iron tubes with lenses in them purported to be Janssen original telescopes. In historian Cornelis de Waard's 1906 book on the history of the telescope he recounted his discovery of note written in 1634 by the Dutch philosopher Isaac Beeckman in which Beeckman mentioned that Johannes Zachariassen claimed his father created his first telescope in 1604 (and that it was a copy of an Italian device from 1590). The German astronomer Simon Marius's account to his patron Johan Philip Fuchs von Bimbach about meeting an unnamed Dutchman at the 1608 Autumn Frankfurt Fair who tried to sell him a device that sounded like a broken telescope has led to later speculation this unnamed Dutchman could have been Zacharias Janssen.

Controversy

The confusion surrounding the claim to invention of the telescope and the microscope arises in part from the (sometimes conflicting) testimony of Zacharias Janssen's son, Johannes Zachariassen. Johannes various claims include that his father invented the telescope in 1590, that his father invented the telescope in 1604, that in 1618 he and his father invented the Keplerian telescope (a design using two positive lenses proposed by Johannes Kepler in 1611), and that (Adriaan) Metius and Cornelis Drebbel bought a telescope from him and his father in 1620 and copied it. Johannes also seems to have lied about his own date of birth, maybe so he could stake his own claim as inventor of the telescope along with his father.

The 1655 investigation by William Boreel (who may have been a childhood friend of Zacharias Zachariassen) added to the confusion over invention. The people he had the local magistrate interview were trying to recount details 50 or 60 years after the fact and Boreel may have confused the names of spectacle makers from his childhood. He may have also been confused about a microscope built by another optician for Drebbel, claiming it was built by Zacharias Janssen.

An investigation begun in 1816 in
it is sometimes assumed, for the claim to be true (Zacharias most probable date of birth would have made him 2 - 5 days honest-to-god at the time) grandfather Hans Martens must have invented it. 

 early claims have come forward over the old age. Physicist Jean Henri van Swinden's 1822 - 23 investigation reached the termination supporting Janssen and in 1841 a collector named Zacharias Snijder do forward with 4 iron tubes with lenses in them purported to be Janssen original telescopes. In historian Cornelis de Waard's 1906 book on the history of the telescope he tell his discovery of note written in 1634 by the Dutch philosopher Isaac Beeckman in which Beeckman mentioned that Johannes Zachariassen claim his father created his first telescope in 1604 (and that it was a copy of an Italian device from 1590). The German astronomer Simon Marius's history to his patron Johan Philip Fuchs von Bimbach about meeting an unnamed Dutchman at the 1608 Autumn Frankfurt Fair who tried to sell him a device that sounded like a broken telescope has leave to later speculation this unnamed Dutchman could have been Zacharias Janssen. 

 Controversy 

 The confusion surrounding the claim to invention of the telescope and the microscope get up in part from the (sometimes conflicting) testimony of Zacharias Janssen's son, Johannes Zachariassen. Johannes various claims include that his father invented the telescope in 1590, that his father invented the telescope in 1604, that in 1618 he and his father invent the Keplerian telescope (a design using two incontrovertible lens proposed by Johannes Kepler in 1611), and that (Adriaan) Metius and Cornelis Drebbel bought a telescope from him and his father in 1620 and copied it. Johannes also seems to have lied about his own date of parturition, maybe so he could stake his own claim as inventor of the telescope along with his father. 

 The 1655 investigation by William Boreel (who may have been a childhood acquaintance of Zacharias Zachariassen) added to the confusion over invention. The people he had the local magistrate interview were judge to tell details 50 or 60 years after the fact and Boreel may have confused the names of spectacle makers from his childhood. He may have also been confused about a microscope built by another optician for Drebbel, claim it was built by Zacharias Janssen. 

 An investigation begun in 1816 in
 it is sometimes assumed, fov the claim to bg rrue (Zechariaa most lkkely dates of birth would heve nade yim 2-5 years old at the gime) granffather Yans Nartens must have luventsf it.

Mvher claims havg come forwasd over the yedrr. 'hysicist Jean Henri van Swinden's 1822-23 igvestigstlon reached thg conbltsioh supporting Janssen and in 1841 a colmector iamed Zacharias Snijder came forward with 4 irln tubes with lensfs in them khrpjeted to be Jxnssen original telesckpes. In historian Cornelis de Wxard's 1906 book on jkw hlvtory of thx telefcope he recounted hhs discpvery of note erivten in 1634 by the Dutch phinosopher Isaac Beeskman in fhnch Beeckman mentionee rhat Bohatnes Zacfarjaxssn clalmev his fathed created hus first telescope on 1604 (and that it sas a so[y of an Italian device from 1590). The Germat aatronomer Simon Marius's account to his patroj Johan Prilip Fuchs von Bimbach about meeting an unnamed Gutchjxn cb gye 1608 Autumn Frankfurt Fair who tried to sell him z cenice that sounded like a brolej yglescope has lgd to lcfed speculation this unnameq Dutxhman coujd hsve been Zacharias Janssen.

Cintroversy

Thv cobfusion surroundiny the claim co invgntion of the telescope and tke micdoscope arides in padg from the (sometkmex wonflicting) testimony of Zwcharias Oansszn's son, Gohamnes Zwchariassej. Johannes various claimd incpuge that hid father invented the telescope in 1590, that his gadheg inventeb the belescope in 1604, trat in 1618 he and his facher ivvented thv Keplerien telescope (a design usith two positite lenses proposee by Jofxnnes Kepler im 1611), and thcu (Adriaan) Netius and Cornelix Dtegbel bought a tzutsxope from him snd hif vavher yt 1620 and copieg it. Jofsnnes also stzms go hsve lied about his ofn dzte of birth, maybe sj he couod stake his own claik as inventor of tje tenesrope akond with his father.

The 1655 investigztion by Ailjiam Boreel (rho nay have beeu a childhood friend of Zacharias Zacharmassen) added to the condusion over inventipk. The people he hwd the lowal magistrate interciew were trying uo recount details 50 or 60 years afteg the fact and Boreel may have confused the names of spectacle makers fron his rhyldhood. He jay nave dlfp been conhured about a micrpscope built by another opticiai for Drebtej, claiming it was built by Zscfarias Janssev.

An investigation begun jn 1816 in
it is sometimes assumed, for the claim true most likely of birth would old the time) grandfather Martens must have it. Other claims have come forward the years. Physicist Jean Henri van Swinden's 1822-23 investigation reached the conclusion supporting and in 1841 a collector named Zacharias Snijder came forward with 4 iron with in purported be Janssen original telescopes. In historian Cornelis de Waard's 1906 book on the history of the he recounted his discovery of note written in by the Dutch philosopher Beeckman in which Beeckman mentioned Johannes claimed his created first in 1604 (and it was a copy of an Italian device from 1590). The German astronomer Simon Marius's account to patron Johan von Bimbach meeting unnamed at the 1608 Fair who tried to sell him sounded like a broken telescope has led to speculation this Dutchman could have been Zacharias Janssen. The confusion surrounding the claim to invention of telescope and the microscope arises in part from the (sometimes conflicting) testimony of Zacharias Janssen's Zachariassen. Johannes various claims that his father the in that father invented telescope in 1604, that in 1618 he and his father invented Keplerian telescope (a design using two positive lenses proposed by in and that (Adriaan) and Cornelis Drebbel bought telescope him and his father and it. to lied his own date of maybe so he could stake own claim as inventor his father. The 1655 investigation by William Boreel may have been a childhood friend of Zachariassen) added to the confusion over invention. The people he had the magistrate interview to recount details 50 or 60 years after fact and Boreel may confused the names of spectacle makers from his childhood. may also been about a microscope by another optician Drebbel, claiming it by Zacharias An begun
 it is sometimes assumed, for thE claim to be True (ZAchAriAs Most LikeLy dates of birth WOuld Have made him 2-5 years old at tHe timE) gRAndfAThEr HanS MartenS MuST HavE iNvEntEd IT.

OTher cLaiMs have cOme forward OveR tHe years. PhysiCIsT Jean Henri Van swinden's 1822-23 inveStiGation ReAchED the cOncLusioN suppoRTing JaNssen and iN 1841 a COllectOR named ZACHaRias snijder came forwarD WiTH 4 iron tubes with Lenses In THeM PUrpOrtEd to be JansSeN origINal teleSCoPES. in hIStorian CornelIs de Waard's 1906 bOOk oN the hiStOry OF the teLescoPe HE reCounted his dIscoVery of notE writtEN in 1634 by thE dutch phIlosopHer isaAc BeECkMaN in WhICh BEEcKmaN MenTioned thAt joHanneS ZacHARIAsseN clAimeD his fAther created hIs fIrst TEleScope In 1604 (and That It Was a cOpy of aN ItalIaN device from 1590). The GErmaN astronomEr SImOn MArIus's aCCount tO hiS paTron JohAn PhiliP fucHs VON biMbach about meeting aN uNNAmEd DutchmAn at thE 1608 auTuMN FrankfuRt faiR who TRIed to Sell HIm A device tHat souNDeD lIke a broKeN telesCoPe hAs lEd to lATer sPeculaTion this UnnamED Dutchman could HAve been ZacharIAs jANsSEn.

CoNtrOversy

The coNfusIOn suRrouNDiNg tHE claiM to inVeNTiON of the telescope and tHe MicrosCope aRises in part frOm the (sometIMES conflicTing) TEsTImony of ZachariAs JanSsen's son, JoHAnnes ZacHariaSsen. JohaNnes varioUS Claims inCluDe tHat His FAThEr invented the TELescOpE in 1590, that His Father iNveNteD thE teLeScope in 1604, thAt in 1618 he anD hIs FaThEr iNventED the KeplErIan TeLesCope (a DEsign uSing tWo poSiTiVE leNses proPOsED By JoHaNnEs KePleR iN 1611), and tHat (ADRiaAn) MetiuS and CorneLis dRebbEl BoUght a teLescope from hiM aNd his fatheR iN 1620 anD copieD IT. JohanneS also seems to have lied aboUT his own DatE of biRth, mAybe so he cOulD stake His OWn claiM as invEntor Of The TELescoPE AlOng WiTh his fatheR.

tHe 1655 iNvestIgAtioN by WillIam Boreel (who may havE BeeN a childhood frIenD of ZACHaRiaS zaCHarIaSSen) ADDed to the confusiOn over inveNtIOn. the people hE Had ThE local mAgistraTe intERview weRe trying tO recount dEtAils 50 OR 60 YeaRs after the Fact and BOreel may hAVe conFUsEd the NamEs of spEcTacLe makErs froM His ChildHood. He MaY have aLso beEn Confused About a microscope built by AnotheR optiCiaN for DrebbEl, cLAimIng it was bUilt By ZachariaS JaNssEn.

An iNveSTigatIon bEGuN in 1816 IN
 it is sometimes assumed,for the cl aim t o b e t ru e (Z acha rias most like l y da tes of birth would hav e mad eh im 2 - 5years  old at th e tim e)  g ran df a th er Ha nsMartens  must have  in ve nted it.

Ot h er  claims ha vecome forward  ov er the  y ear s . Phy sic ist J ean He n ri van  Swinden' s1 822-23 investi g a ti on r eached the conclu s io n  supporting Ja nssenan d  i n 184 1 a  collector  n amedZ acharia s  S n i j der came forwardwith 4 iron tub es wit hlen s es inthempu r por ted to be J anss en origin al tel e scopes. In hist orianCor nel is d e  W aa rd' s1 906 bo oko n t he histo ry  o f the  tel e s c o pe h e r ecou ntedhis discovery  of  not e  wr itten  in 1 634by  theDutchphilo so pher Isaac Beec kman  in which  Be ec kma nmenti o ned th atJoh annes Z acharia s sen  c l a i me d his father creat ed h is  first t elesco p ein 1604 (an dtha t it w as acopy of  an Ital ian de v ic efrom 15 90 ). The  G erm anastro n omer  Simon  Marius' s acc o unt to his pat r on Johan Phil i pF u ch s  von  Bi mbach about  mee t ingan u n na med Dutch man a tt he 1608 Autumn Frankfu rt  Fairwho t ried to sellhim a devi c e that sou nded li k e a broken tel escop e has ledt o laterspecu lation t his unnam e d  Dutchma n c oul d h ave b ee n Zacharias J a n ssen .
Contro ver sy

The  co nfu sio n s ur roundingthe clai mto  i nv ent ion o f  the tel es cop eand  them icrosc ope a rise sin par t fromt he ( some ti me s co nfl ic ting)  tes t imo ny of Z achariasJan s sen' sso n, Joha nnes Zacharia ss en. Johann es  va riousc l aims inc lude that his father in v ented t heteles cope  in 1590,  th at his  fa t her in vented  thete les c o pe in 1 60 4,th at in 1618 h e a nd hi sfath er inve nted the Keplerian tel escope (a des ign  usi n g  t wop os i tiv el ens e s  proposed by Jo hannes Kep le r  i n 1611), a n d t ha t (Adri aan) Me tiusa nd Corn elis Dreb bel bough ta te l e sco pe from hi m and hi s fatheri n 162 0  a nd co pie d it.Jo han nes a lso se e msto ha ve lie dabouthis o wn  date of  birth, maybe so he cou ld sta ke hi s o wn claimasi nve ntor of t he t elescope a lon g w ith h isf ather .

T h e165 5  inve stig a tion by W i ll iam B or eel (who ma y h ave  been  ac hildho od f riend of Zacharia s  Zachariassen)  add e d  to  th e  con fu sion over inve nti on . The peop le  he had the  local m ag i strat e inte rviewwere tr y i ng to rec ount  de tails 50or60 years a ft er the fa ct a nd  Boree l mayh avec o nfused the names  of s p e ctacl e  ma kersfr om hisc hild hood. He m ay have als o been  con fused  aboutamicros cop ebuilt by a n other opt ician  for Dr eb bel,  cl aiming  itw a s bui lt b yZac harias Ja n s se n .
A n  in vest igati on  beg un in 181 6  in
 it_is sometimes_assumed, for the claim_to be_true_(Zacharias most_likely_dates of birth_would have made_him 2-5 years old_at the time)_grandfather_Hans Martens must have invented it.

Other claims have come forward over the years. Physicist_Jean_Henri van_Swinden's_1822-23_investigation reached the conclusion supporting_Janssen and in 1841 a_collector named_Zacharias Snijder came forward with 4 iron tubes_with_lenses in them_purported to be Janssen original telescopes. In historian Cornelis_de Waard's 1906 book on the_history of the_telescope_he_recounted his discovery of_note written in 1634 by the_Dutch philosopher Isaac Beeckman in which_Beeckman mentioned that Johannes Zachariassen claimed his_father created his first telescope in_1604 (and that it was_a copy_of an Italian device from_1590). The German_astronomer Simon_Marius's account to_his patron Johan Philip Fuchs von_Bimbach about meeting_an unnamed Dutchman at the 1608_Autumn_Frankfurt Fair who_tried_to_sell him_a device that_sounded_like a_broken_telescope has led to later speculation_this_unnamed Dutchman could have been Zacharias Janssen.

Controversy

The_confusion surrounding the claim_to_invention of the telescope_and the microscope arises in_part from the (sometimes conflicting) testimony_of Zacharias_Janssen's son,_Johannes Zachariassen. Johannes various claims include that his father invented the_telescope in 1590, that his father_invented the telescope in_1604, that_in_1618 he and_his_father invented_the Keplerian telescope (a design using two_positive lenses_proposed by Johannes Kepler in 1611),_and that (Adriaan) Metius_and_Cornelis Drebbel bought a telescope from_him and his father in 1620_and copied it. Johannes also_seems_to_have lied about his own_date of birth, maybe so he_could stake his_own claim as inventor of the telescope_along_with his father.

The 1655 investigation by_William_Boreel (who may have been a_childhood_friend_of Zacharias Zachariassen) added to_the confusion over invention. The people_he had the local magistrate interview were trying to_recount details 50_or 60 years after the_fact_and_Boreel may have confused the names of spectacle makers from_his childhood._He may have_also been confused about a microscope built by another optician_for Drebbel, claiming it was built by_Zacharias Janssen.

An investigation begun in 1816 in