relating to the Construction of the Heavens , 285 
from a superior preponderance of the nebulous matter in those 
places ; but attraction being a principle which never ceases 
to act, the consequence of its continual exertion upon this ne- 
bula will probably be a division of it, from which will arise 
three or four distinct nebulae In the same manner its opera- 
tion on the diffused nebulosities that have many different 
bright places, will possibly occasion a breaking up of them 
into smaller diffusions and detached nebulae; but before I pro- 
ceed with conjectures, let us see what observations we have to 
give countenance to such expectations. 
8. Of double Nebulce with joined Nebulosity „ 
In addition to the instances referred to in the preceding 
article, of nebulae that have more than one centre of attraction 
i give the following list of what may be called double ne- 
bulae.* 
The 316th nebula in the second class to which in the cata- 
logue is joined the 317th, consists of “ two small faint nebulae 
“ of an equal size within 1' of each other. Each has a seem- 
“ ing nucleus, and their apparent nebulosities run into each 
“ other. Their relative position is in a direction from south 
preceding to north following.” See fig. 6 , a and b. 
Each of the fifteen objects referred to contains two nuclei 
or centers of attraction, and if the active principle of conden- 
sation carries on its operation, a division of their at present 
united nebulosities must, in the end, be the consequence. I 
# See I. 56, 176, 178, 193. II. 80, 271, 309, 3 16, 832. Ill, 45, 644. IV. 8, 28. 
Connoiss. 27, 51. 
