Mr, Bowditch on the Transit of Mercury, Nov. 9, 1769. 279 
; ongitude 
D-© Par.long. Par.lat. Daug.sem. conjunction. W Greenwich. 
Beginning 17’ 57/0 23! 248 16’ 39"-81 11h. 42'02".3 4h. 38’ 42°"7 
3 End —10 42°3 2102 4 1641 49 t1 41 O07 *7 4 39 373 
The difference of nearly a minute, in the times of the conjunction 
deduced. from the two contacts, arises probably from some mistake in 
noting the time of the beginning of the eclipse, since the end gives 
nearly the same result as the eclipse of the sun of Sept. 17, 1811, as 
was mentioned in the former part of this paper. 
Mr. Ferrer in a letter to President Webber, mentions that the end 
of the eclipse at Williamsburg, (Virginia) was at Of. 15’ 14” mean 
time. This would make the longitude 5%. 7 46’, which being nearly 
a minute more than other observations make it, and no account hav- 
ing been given of the observation by which we might judge of its ac- 
~ curacy, I have concluded to reject it. 
Transit of Mercury of Nov. 9, 1769. 
This transit was observed in Philadelphia, Norriton, and Salem. 
It was invisible in Europe. The difference of meridians of Philadel- 
phia and Norriton is known to be 52 seconds in time, by a trigonom- 
etrical survey, and the observations made there, compared with those 
at Salem, would have given the difference of meridians of Salem and 
Philadelphia, but on calculating the observation at Salem, (which was 
made at a place 1-2 east from the place where my observations of the 
eclipse of Sept. 17, 1811 were made) I found the times were too 
great by above a minute, owing probably to the inaccurate method of 
regulating the watch by a common meridian line. This rendered the 
observation useless. fa EL SCs ME Pe ise iee 
Deductions from the eclipse of the sun, of October 27, 1780. 
The observations of this eclipse, made at Chelsea, Beverly, “ee 
port, Providence, Long-island, and Charlotte-town, are given in the 
