[ 333 ] 
but a very Inconliderable difference in the paralladtic 
time ; as will fufficiently appear from an infpedtion 
of the following Table, which contains the joint ef- 
fect of the parallaxes of longitude and latitude in 
accelerating the times of the two internal contadfs at 
Tornea°, Kittis, and Wardhus, for each of which 
places the paralladfic angle, or the angle made by a 
vertical circle with the orbit of Venus, was carefully 
computed. 
Firft 
Second 
Total 
Total 
Difterenci 
intern. 
intern. 
effcdl of 
effedl of 
for i'' ol 
contadl 
contadl 
|j 
00 
par.= 9",7 
parallax. 
/ / 
, . 1 
/ // 
Tornea° 
6 53 
4 47 
4- I I 40 
4-12 58 
1 IS 
Kittis 
6 51 
4 43 
4 - 1 1 34 
+ 12 51 
I 17 
Wardhus 
6 38 
4 41 
4-11 19 
+ 12 37 
I 18 
Having determined the gveated: effedl of parallax 
in lengthening the total duration at fuch places to 
which obfervers may conveniently be fent, let us ex- 
amine how far we may be enabled to obtain obferva- 
tions in fuch parts of the earth’s furface where the 
effedl of parallax will be contrary j and confequently 
where the total duration will be as flaort as poffible. 
By the affiftance of calculation it may be found, that 
in the latitude of about 54° South, and in 155° of 
Weft longitude nearly, the total duration will be the 
fhorteft, when the fun’s altitude is 5° j or in about 
47° of South latitude under the fame meridian, when 
the fun is 10° high. And accordingly, by computing 
the paralladllc angle for the latitude of 55° South, 
and the meridian oppofite to that of Tornea'’, I find 
