[ 626 ]. 
The angle of the orbit of Venus 
30 io 
/ // 
with the ecliptic - - - - — - 
The diftance of the centers of the 
Sun and Venus as feen from the o 932 
The difference of the parallaxes i 
of the Sun and Venus — - - J 0 0 2I, 35 " 
I fhall now give the method I followed in thefe 
calculations. 
In Tab- XTX. Fig. ift. Let F G reprelent the ho- 
rizon, Z V H a vertical circle paffing thro’ the center of 
Venus, PVR a circle of declination, B V a circle of 
latitude, E C the ecliptic, O V N the orbit of Venus, 
VL the parallax of altitude, VN the parallax of 
lo gitude, LN the parallax of Latitude, Z VP the 
angle of the vertical with the circle of declination, 
B.VP the angle of the equator with the ecliptic, 
Z V B the angle of the vertical with the circle of 
latitude, E V O the angle of the orbit of Venus with 
the ecliptic, ZVO the angle of the orbit of Venus 
with the vertical, ZP the complement of the lati- 
tude of the place, V P the complement of the decli- 
nation of the planet, Z P V the horary angle or dis- 
tance of the planet from the meridian, ZV the com- 
plement of the altitude of the planet. 
In the triangle ZPV, the tides ZP and PV and 
the angle ZPV are given, therefore the angle ZVP 
may be found, and all'o the fide Z V, and as the par- 
allax of altitude is to the horizontal parallax as the 
cofine of the apparent altitude is to the radius, there- 
fore L V is found. B V P added to or fubtradted from 
ZVP, as the nature of the cafe requires, leaves the 
center of the earth 
angle 
