134 ESSAYS anp OBSERVATIONS 
blem therefore is reduced to this: The 
mean anomaly ofa planet being given, to 
find the anomaly of the excentric and the 
coequate anomaly, 
e 
PROP. VI.. Prosi. IV. Fig. 6. 
Let AP be the greater axis of a planet’s 
orbit, S the focus the place of the fun, 
A the aphelion, P the perihelion; up- 
on AP let the femicircle ABP be de- 
{cribed ; let C be the center, and let 
the angle ACB be the mean anomaly 
of the planet at any given time: It is 
required to find the anomaly of the ex- 
centric. 
Jorn SB, and draw CD ‘parallel to SB 
meeting the circle in D:. JoinSD in BD: 
Take the arc DG, fo that the fine of the 
angle BCD may be to the tangent of the | 
angle CDS, as the excefs of the arc BD 
above its fine to the arc DG; and join 
CG : The angle ACG will be nearly the a- 
nomaly of the excentric. 
Join 
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