[ 3S6 ] 
Obfervatlon of the Transit of Vrnus. 
I chofe to obferve the tranfit with the 2 feet te- 
lefcope, as I fuppofed moft of the obfervatlons in 
other parts would be made with telefcopes of that 
fize ; and I ufed a power that magnified 90 times, 
which gave a very diflindt view of the fpots then on 
the Sun, Soon after two o’clock, 1 began to look 
on the Sun’s upper limb, where the Planet was to 
enter. The firll: impreffion I perceived was at 
2^ 27' 51", by the clock, the Sun being then per- 
fectly clear. 1 then reftcd my eye, which was pretty 
much fatigued, to prepare it for the total ingrefs or 
interior contaCt. At 2^ 45' 15^', I began to be 
doubtful whether the internal contaCl was not formed; 
but at 20" was fatisfied that it was paft, the Sun’s 
limb being reftored to its integrity, in the place where 
it had been interrupted by the Planet. During this 
interval of near 5", there Teemed to be a dulkilhnefs 
in the place of contaCt ; my idea of which is well re- 
prefented by Mr. Dunn’s figure of what he calls the 
grey contaCf, in Phil. Tranf. Vol. LIT. Tab. vii, 
p. 190. 
By the foregoing equal altitudes it appears, that 
the clock was now 2 ! 13'' 4- too flow, I therefore 
flate the obfervatlon as follows 
Apparent time». 
b / n 
1 Firft vlfible impreffion of Venus upon the Sua. 2 30 4 
Internal contad 47 3 ° 
This time of internal contaCt, I think, cannot differ 
above 2" from the truth, and perhaps may not 
differ 
