relating to the sidereal part of the Heavens.. 
mass. The Rev. Mr. Vince, PJumian Profes&or of A^»tronomy 
“ at Cambridge, saw it in the same telescope as ‘described.’' 
27, 1791* 40 telescope, power 370. “ The 5th 
“ of the Connoiss. is a beautiful cluster of stars ; I counted 
“ about 200 of them ; but the middle of it is so compressed 
.that it is impossible to distinguish the stars."* 
January 5, 1807. 20 feet telescope. Space-penetrating 
power 75,08. Magnifying power 157.3. “ The 56th of the 
‘‘ Connoiss. is a globular cluster of very compressed and 
“ very small stars. They are gradually more compressed 
“ towards the centre." 
May 26, 1786. 20 feet telescope. The 80th, of the Con- 
noiss. is a beautiful, round cluster of extremely minute and 
“ very compressed stars about 3 or 4' in diameter; by the 
increasing compression of the stars the icluster is uvery gra- 
“ dually much brighter in the middle." 
May 16, 1787. 20 feet telescope. “ The 13th of the Con- 
“ noiss. is a most beautiful cluster of stars. It is .exceedingly 
* A 40 feet telescope should only be used for examining objects that other instru- 
ments will not reach. To look through one larger than required is loss of time, which, 
in a fine night, an astronomer has not to spare ; but it ought to be known that the 
opportunities of using the 40 feet reflector are rendered very scarce by two material 
circumstances. The first is the changeable temperature of the atmosphere, by which 
the mirror is often covered with the condensation of vapour upon its surface, which 
renders it useless for many hours ; and in cold weather by freezing upon it for the 
whole night, and even for weeks together ; for the ice cannot be safely taken off 
till a general thaw removes it. The next is that, with all imaginable care, the polish 
of a mirror exposed like that in the 40 feet telescope, though well covered .up, -will 
only preserve its required lustre and delicacy about two years, The-three observations 
I have given must consequently be looked upon as having been made by three differ- 
ent mirrors ; but if we will have superior views of the heavens, we must submit to 
circumstances that cannot easily be altered. 
N n 2 
