[ +72 ] 
the Do&or’s own tables, than he had fuppofed in his cal- 
culation made from the Rodolphine tables corrected : 
and therefore the planet’s egrefs could not have been 
obferved at Port Nelfon. Having made a computa- 
tion for a place in North America fituated $ h . 3 o' to 
the weft of Greenwich, and in the 60th degree of 
latitude - } and alfo for a place to the eaft of Ganges, 
and 6 h . 30' to the eaft of Greenwich in the latitude 
of 22 0 . 42' north, that the places might be nearly 
lituated in the fame circumftances with the mouth of 
the Ganges and Port Nelfon, I find that the interval 
between the two contacts would be but 4.'. 56" 
longer in America than in the Eaft Indies, fuppoling 
the Sun’s parallax 12A5, and the inclination of 
Venus’s path 14°. 40' to the equator. 
And here perhaps it may not be altogether unnecef- 
fary to enquire how far the miftake which Dr. Hal- 
ley committed, by ufing the difference of the two an- 
gles inftead of their fum, would influence the times 
of the tranfit as feen at Ganges and Port Nelfon. 
For this purpofe I made ufe of the fame elements 
which Dr. Halley has given in his paper, and calcu- 
lated the angle of the vertical with the orbit of Venus 
at the two internal contacts at both places, fuppoling 
the orbit to be inclined firft only 2°. 1 8' to the equa- 
tor, agreably to Dr. Halley’s fuppofition, and alfo 
1 4 0 . 40'. and I found that the duration would be 
15'. 13" longer at Hudfon’s-Bay than at the Ganges 
upon the firft fuppofition ; and 14'. 44", if the circles 
be duly inclined to each other ; the difference being 
only 29 feconds. It has already been found by cal- 
culation, fuppoling the latitude of Venus to be about 
9 4 minutes, that the difference of duration at the 
two places would have been only 4'. 56" t It may 
