9 



M A T li E M A T I C At ^a n o 



HEN it became more generally known that 

 there would be a tranfit of Venus iu 17695 and 

 the advantages which were like to accrue to aftronomy^ 

 and confequently to navigation and chronology, from pro-* 

 per obfervations of it, Mn Josefh Bkown*, a very re- 

 fpedable merchant of Providence, being very defirous, if 

 polhble, to obtain an obfervatlon of it, was pleafcd to ad^ 

 vife with me, concerning an apparatus fuitable for fuch 

 an obfervatlon, and to know if we ftiould be able to obfcrve 

 the tranfit with the neceffary precifion for anfwering the 

 important defign ? My anfwer gave him fo much fatisfac™ 

 tion in the matter, that he immediately fent his orders to 

 his correlpondent in London, to procure the inftrumentSt 

 His orders were accordingly executed with fidelity and 

 difpatch; and the inftruments arrived in Providence about 

 one month before the tranfit. Our apparatus was made 

 by MefTieurs Watkins and Smith, London; it confided of 

 a three feet refleding telefcope, with horizontal and vci 

 tical wires for taking differences of altitude and azimuths 

 adjufted with fpirit-levels at right anglcsj and a divided 

 arch for taking altitudes; a curious heliofcope^ to_ 

 with a micrometer of a new and elegant conftruSion, with 

 rack motions, and fitted to the telefcope. Befides the be 



fore mentioned inftruments, we had a fextant belonging 

 to the government, made in Newport, by Mr, Benjamin 

 King, under the diredion of Jofeph Harrifon, Efq* now 



coUedor of his Majefty's Cuftome for the port of Bofton; 

 its limb was divided to five mileSj and by a vernier index 

 to five fecondsf* We had two good clocks, one of which 



was made in Providence, by Mr. Edward Spalding." 



was 



* Roadinp: Mr. Winthrop'fl account: of the tranfit in Jy6i^ wae wluvt firO: occafioncd Mr. 

 BliOWN to fcml for a teldeopv% fitted in the mannci' Mr, Winthrop there defcribcs; aftt^r- 

 w^rcis, taking notice of tha application gf the Amtrkm HUlolophiesl Society to tlie AiTcnihly 



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icr 







and fervantSj ijj making tht; necelliiry previous cxpcnmants and pfcparutiDns. 



Mr. Redwood, for lb public fpin ted an adion, will receive the thanks of every wcU-wiilicr 

 to fciencc. 



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