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rain. I waked for the fecoi-:! ; the Sun then was 
pretty clear. But there were fome vapours, which 
cauied fuch great undulations as to hinder me from 
.feeing the dilc of the Sun, and that of Venus, 
well defined. At 7^ 38' 45'^, apparent time, or 
7^ 38^ 43'', reduced to the meridian of the Royal 
Oblervatory, the fecond contadl appeared decifively to 
me. Two feconds after, a very fine thread of light 
appeared between the limb of Venus and that of the 
Sun ; fo that in my obfervation there is not an uncer- 
tainty of two feconds in the moment of the internal 
contadt. After this obfervation, I viewed the Sun 
with different glaffes, which rendered him alter- 
nately red and white. I faw Venus, with this lafl 
colour, with a crefeent of a blueifli colour ; and a 
little inclined towards the limb of the Sun : Vvdth the 
glafs which made the image of the Sun red this 
crefeent difappeared j but I faw Venus flattened in the 
diredfion of the crefeent. I meafured the Sfreatefi: and 
O 
leaf! diameter; the greatefi: was 5 6'^!, and the lca(t 
53^1. Perhaps this crefeent was only vifible by the 
effedt of fome optic illufion; but I relate only what I: 
faw. At 7^ 52' 8^^, apparent time', I meafured the 
interval between the limb of Venus and that of the 
Sun, which I found 46'^!; and at 7^ 58' 4''^, the 
firfl: limb of Venus touched the horizon. 
By a letter from M. I’Abbe Bourriotto Mr. Magal- 
haens it appears, that Meff. de Pouchy and Bailly,at the 
Meute, each made ufe of refiedting telefcopes of 30 
inches focus and 4I inches aperture ; that M.Borymade 
ufe of an achromatic telefcope of 5 feet focus, and 2 
inches aperture ; and M. I’Abbe Bourriot made ufe of 
a very good achromatic telefcope of 6 feet long, and 2 1 
inches aperture, madebyhimfelf, magnifying 1 20 times., 
VoL. LIX. C c c LI. Tranfu 
