NOTICES AND ABSTRACTS 
OF 
MISCELLANEOUS COMMUNICATIONS 
TO THE SECTIONS. 
MA'THEMATICS AND PHYSICS. 
On the mean Apsidal Angle of the Moon's Orbit. By Dr. Forzss. 
By limiting the terms in the expression of the integral equation to 
the first four, viz. those depending on 
cosc @ — a,cos20—2m042(,cos20—2m0+2B—Oc+a 
or the evection, and cos 26—2m6+4% + cv — a, he derived the 
number expressing the ratio of the apsidal angle to the whole circle, 
and found it to be 00843; the result given in the Mécanique Céleste, 
by Laplace, being the same. A decided influence was ascribed to 
the inclination of the moon’s orbit to the ecliptic, and the corrections 
that require to be made for it; also, to the value due to h, or the space 
described by the radius vector in the unit of time, in the disturbed orbit, 
compared with the same in the simple elliptic theory. The circum- 
stance that this quantity may be so easily determined presents a beau- 
_ tiful evidence of the law of gravitation, and of the truth of the New- 
_ tonian theory, and may ‘be of material importance in the theory of the 
moon. 
An Account of the Observatory erecting near Glasgow. By Professor 
NICHOL. 
He stated that when he was appointed to the office he holds in the 
University, the state of the Macfarlan Observatory gave him much anx- 
iety, as in consequence of its age it was in nowise fitted to be of service 
1840. B 
