C 501 ] . 
the limb of the Sun; at which inftant I eftimated 
the internal contact. Many have this year feen the 
fame phenomenon at the total entry of Venus. I was 
in expectation of it ; neither I or my aftociates per- 
ceived any fuch thing. In 1761 the Sun’s limbs were 
mod exquifitely well defined; in 1769 they undulated, 
efpecially at the beginning of the entry ; at the total 
entry the undulation was confiderably lefs, and not- 
withftanding this undulation I believe our obfervation 
a good one. On comparing the duration of the 
tranfit obferved at the Prince of Wales’s Fort, with 
that of Father Hell, at Wardhus, I find, on a firft 
calculus, which I believe at leaft nearly exadt, that the. 
Sun’s parallax is g".i 1. 
Auguft 16, at St. Croix in TenerifFe, the firft 
fatellite emerged at 9 h 16' 5", apparent time. 
I am, &c. 
Paris, March 10, 1770* 
XLI. OK 
