penetrating into Space by Telescopes. 73 



May 3, 1783. I viewed the nebula between y and a Ophiuchi, 

 discovered by Mr. Messier, in 1764. 



" With a 10-feet reflector, and a magnifying power of 250, 

 " I see several stars in it, and make no doubt a higher power, 

 " and more light, will resolve it all into stars. This seems to be 

 " a good nebula for the purpose of establishing the connection 

 *' between nebulae and clusters of stars in general." 



June 18, 1784. The same nebula viewed with a large New- 

 tonian 20-feet reflector; penetrating power — '^1— — "ZlL. 

 = 61,18 ; and a magnifying power of 157. 



" A very large and very bright cluster of excessively com- 

 " pressed stars. The stars are but just visible, and are of une- 

 " qual magnitudes : the large stars are red ; and the cluster is 

 " a miniature of that near Flamsteed's 42d Comae Berenices. 

 "RA 17* 6' 32"; PD 108 18V 



Here, a penetrating power of 29, with a magnifying power of 

 250, would barely shew a few stars ; when, in the other instru- 

 ment, a power 61 of the first sort, and only 157 of the latter, 

 shewed them completely well. 



July 4, 1783. I viewed the nebula between Flamsteed's 25 

 and 26 Sagittarii, discovered by Abraham Ihle, in 1665. 



" With a small 20-feet Newtonian telescope, power 200, 

 "it is all resolved into stars, that are very small and close. 

 " There must be some hundreds of them. With 350, 1 see the 

 " stars very plainly ; but the nebula is too low in this latitude 

 " for such a power." 



July 12, 1784. I viewed the same nebula with a large 20-feet 

 Newtonian reflector ; power 157. 



" A most beautiful extensive cluster of stars, of various mag- 

 " nitudes, very compressed in the middle, and about 8' in 



MDCCC. L 



