io 6 Mr. Herschei/s and Mr. South’s observations of the apparent 
sight ; but it is most probable that the orbit is elliptic, and 
merely projected into a circle ; for if we examine the forego- 
ing angles attentively, we shall find that the angular velocity 
is sensibly retarded ; for, in the period of 20.0 years elapsed 
between the observations of 1759 and 1779, we find an angle 
of 23°.7 described, being T.185 per annum. In the next 
period of 22.2 years to the measures of 1802 (which from 
the number taken may be relied on), 2T.4 only were de- 
scribed, giving an angular velocity of o°.964, or about the 
average ; while in the third (and probably most accurate) 
period of 21.1 years, only i 6°.4 were described, giving an 
angular velocity of o°.yyy per annum, being as much below 
the average as that of the first 20 years is above it, 
R.A, 7 h 23 ra . Castor and the faint distant stars. Deck 32 0 17' N. 
South following and south preceding Castor are two mi- 
nute stars C and D, the former about one-third the distance 
of the latter from A, the large star forming Castor. C may be 
called of the 14th ; D the 15th or perhaps the 16th ; C bears 
a tolerable illumination ; D scarcely any. 
The measures of AC tolerably good ; those of AD per- 
haps a little inaccurate. 
Castor continued. 
Position. 
Distance. 
Parts. 
90—19.35'! 
Feb. 14, 1823. 
293- 
19.40 
18.50 
18.45 
Seven-feet Equatorial. 
Measures of AC 
17.20 
1 7-4° 
I 7*45 
19.15 
! 9 . o^ 
Mean 
Z = 
292.40 
0.5a 
Mean - 18.31 
Position = 7i°.2 sf 
Distance == i'.io"i8o. 
291.88 
