[ 5 °° 
Thefe altitudes taken with a quadrant of two 
French feet radius, \ r 6" muft be added to each, to 
correct the error of the quadrant. 
M. de Fleurieu’s were : 
Alt. 
Times by clock. 
Apparent 
times. 
O 
/ 
h / 
// 
h / 
// 
34 
45 
9 22 
28,5 
9 18 
05,80 
34 
*5 
24 
4 J >5 
20 
18,74 
33 
45 
26 
56 
22 
3 3 > 1 9 
32 
45 
3 1 
2 3>5 
27 
0,5 7 
3 2 
J 5 
33 
3 6 >5 
29 
3 1 
45 
3 6 
5 I >5 
3 1 
28,46 
Thefe altitudes were taken with an Englifh quadrant 
of M. Sifion’s make, 16 inches radius. 8 34" are to 
be added to each altitude to corredt the error of the 
inftrument, and for the femi-diameter of the wire. 
On computing thefe altitudes by M. Clairaut’s 
tables, corrected nearly by obfervations made at Paris 
the 30th of May and the 1 Ft of June 1751 , 1 find the 
longitude of Cape Francois, Weft of the meridian of 
Paris, by my own altitudes, 4 h 58' 8", and by thofe 
ofM. de Fleurieu 4 h 58' 2o' / . 
I return to Venus: the time which we have 
noted for the total entry is that when we perceived 
a very llender thread of light between the limbs of 
the o and ? . I judged that the limbs were in con- 
tact, but a few feconds before that inftant. At the 
exit of ? in 1761, the limbs, being not yet in 
contadt, and even fenfibly diftant afunder, I faw as it 
were a dark Ipot detach itfelf from Venus, and gain 
