132 



M A T 11 E M A TI C A 1, 



AND 



with Mr. WiUiam Grants an ingenious mathematician and 

 merchant of London, who came to this city about April 

 or May 1769, that he had alfo propofed an improvement 

 intlie fame inftrument, but different from mine in thefe 

 refpeds, viz. His was a complete femicircle, having the 

 horizon glafs and place of the eye fixed on the arch, and 

 without the fecond fpeculum on the index; which anfwer- 

 cd nearly the fame purpofes, with mine; excepting that 

 by its wanting the above mentioned fpecuUim, it afforded 

 but half the number of obfervations which my conflrudion 

 admits of. The firft intimation I ever had of his improve- 

 ment was from the Rev. Dr. JViUiam Smithy provoft of 

 the college in this city, in May laft; to whom I had fome 

 time before mentioned, that I had thought of fomething, 

 which might be deemed an improvement in the conftrut^liou 



dfi 



M 



Grants upon his informing him that he had improved that 

 inftrument before he left London ; which circumflance in- 

 duced the Dodor to promife him an ihtrodudion to my 



acquaintance, as appears by his certificate in the folloil?ing 

 words, viz. 



a 



REV, SIR, 



Philadelphia, 12th Jan. 1770 



" TN anfvuer to your reqtiejl-^ that IJlooiild certify the oc-- 

 ^ cafton of my introducing Mr. Grant to you^ I do nvell 



remember it to have been as follows. That in(renious 



gentleman having been recomtncnded to my acquaintance^ by 

 fome of my friends to the northvoard^ vue happened^ one 

 day about the beginning of laft May^ to fall into converfation 

 upon fome literary fubje£ls. Among other thimrs^ Mr. 

 Grant mentioned an improvement ivhich he had made in the 

 co7tfrufiion of Godfrey^ s quadrant -^ and ivith a truly com- 

 mtinicative fpirit feemed vuilling to explain the nature of his 

 improvement 'i by making out a draft or fetch of it for me. 

 It happened that I 'a) as tofet out the day follow ins^^ on a 

 journey to Northampton County -^ and Mr, Grant zvas appre-^ 



henfive 



r. 



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