158 



MATHEMATICAL ano 



Sum, ~ 6. 28 



Half Ditto, - 3. i4=Y 



DifF. of the two DifFercnccs, - - 5/ • 2 



II 



Half Ditto, - - 2. 3i~X 



Half interval between the two 

 obfervations of Nov. Sth, 



2^^ V-i^-Z- 



3-4 



» 



Now as one of the obfervations on tlie fecond day ii 

 nearer 12, than on the^r/?, and the other more remote 

 Y is the daily variation of the clock from apparent time 



and the proportion for the equation, agreeable to the rule,is 



24^^ : X : : Z : E. 



-E. 



Or: 



24'^:2',3i" :. 2*^' -' ■" 



3 '4 



I2",0 



The mean noon is, 9^' 58 



^^3l/'+2^• /.4'' 



1 2h. I ' -■ 



35 



// 



To which add the equation, E 



12,9 



And thecorrc<5l time of noon per clock, is - 12. i. 47^9 

 So the clock would here be i'. 47"59 fafter than ap- 

 parent time. 



JccountoftheTx2LnixiofyiE.i^c\jViY over the Sun, No- 

 njember gth^ 1769, as obferved at Norriton in Penn-- 



fylnjania-i by William Smith, Z). D. JohnLukens, Efq\ 

 rs. David Rittenhoufe, and Owen Biddle; 



Mefr 



the 



committee appointed for that objervation^ by the Ame-- 

 rican Philofophical Society. Draivn up and commiini-' 

 cated^ by direction and in bf^half of tbe comniitiee^ by 



Dr. Smith- 



"^ H E inftruments ufcd in this obfervation, were the 

 fame as arealready defcribed, in the Norriton account 

 of the tranfit of Venus. 



The forenoon of November 9th was, for the moft part, 

 cloudy, and made us almoil defpair of obtaining any fa- 

 vourable ^\^\t of Mercury on the Sun; but about one 

 o'clock the Sun fhone out perfedly clear, and continued 



undiilurbcd 



