PHYSICAL ann LITERARY. 15% 
In the orbits of Mercury and Mars, if 
the excefs of the angle BCD above the 
angle A be added to the angle ACD, the 
fum will be nearly the anomaly of the 
excentric reckoned from the aphelion. 
In orbits of {mall excentricity, the an= 
gle ACD is nearly the anomaly of the ex- 
centric; thérefore the following rule will 
give the anomaly of the excentric very 
nearly. | 
From the logarithmic tangent of half 
the mean anomaly, fubtract the difference 
of the logarithms of the aphelion and pe- 
rihelion diftances; the remainder is the 
logarithmic tangent of an angle, which 
eall B: To the angle B, add half the mean 
anomaly ; the fum will give very nearly 
the anomaly of the excentric. | 
4 
EXAMPLE V. 
In the earth’s orbit, the mean diftance 
is to the excentricity as 100000 to 1691. 
Suppofe the mean anomaly from the 
| aphelion 
