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clock of the fame conftruaion, which is fixed in a 
fmall obfervatory in the houfe where I live, and 
which I had altered from fidereal to mean folar time,, 
for the eafier comparifon of thofe clocks, which feve- 
ral gentlemen had procured, in order to obferve this 
rare and curious phaenomenon. The time was de- 
termined by meridional tranfits of the Sun, taken 
with a tranfit infirument made by Mr. Bird, and 
placed very exadtiy in the plane of the meridian, the 
focal length of the objedl-glafs being 43 inches. The 
motion of both docks was perfedly even and 
regular. 
The atmofphere was. fo loaded with vapour, and 
the limb of the Sun was in fuch a conftant date of 
undulation, that I determined to obferve the exter- 
nal contad with a refrador of 12 feet, furnifhed with- 
a fyftem of eye-glafies, and magnifying 68 times. I 
had found, by a previous computation, that the Planet 
would make the fird impredion upon the Sun’s upper 
limb, about nineteen minutes of a degree to the right 
hand of a vertical circle pafiing through the Sun’s 
center. I therefore kept my eye condantly fixed 
upon that part, and at 58'^ apparent time, i 
perceived that a, fmall part of the Planet’s diameter 
had certainly entered upon the Sun’s dific j the im- 
predion,, which I had. obferved for a few. feconds be- 
fore,, having continued upon that part. While the 
Planet was paffing over, the Sun’s edge, I determined, 
with the old micrometer applied to the 12 feetglafs,, 
the following differences of declination betw'een the 
northern limb of the Sun, and the fouthern limb of 
Venus, with as much accuracy as the undeadinefs- 
of the floor, would permit. 
Mean; 
