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LXII. An Account of an Obfervation of tht 
Tran ft of Venus over the Sun> on the 6 th 
of June 1761, at Madrafs ; by the Rev . 
Mr. William Hirft, Chaplain of oik of his 
Majefys Ships in the Eaft Indies : Con- 
tained in a Eetter wrote by him to the Right 
Honourable the Earl of Macclesfield, Pre- 
fdent of the Royal Society . Dated Port 
St. George, if July 1761. 
Read April 22, 
' 7 
r 
M 
R. Hirft began to make obferva- 
tions for regulating his clock, near 
three weeks before the day of the tranftt of Venus,, 
by taking equal altitudes firft, and then by meridional 
paflages of Spica virginrs, and of the Sun ; of which 
latter, he had a good obfervation on the day before 
the tranfit, and another good one the day after it ; fo 
that there can be no doubt as to the accuracy of his 
time. 
The place of his obfervation was fort St. George, 
i>n the top of the governor’s houfe, whofe latitude, 
as determined by many obfervations made not long 
ago, with an excellent quadrant, Mr. Hirft fays, i$ 
13 0 N. and he makes it 3 minutes and 4 feconds. 
of time eaftward of Pondichery. 
Mr. Hirft’s clock was made by M. Gallonde of 
Paris, and was conftru&ed for aftronomical ufes; it 
did not ftop in winding up, and fcaped dead fe^ 
conds. 
The 
