of 500 new Nebulae, and Clusters of Stars. 4^5 
the actual manner in which they are held together; but it will 
always be a desirable step towards information, if the possibility 
of such unions, in many different ways, can be laid before us ; 
and, very probably, those who have more leisure to consider the 
different combinations of central forces, than a practical astro- 
nomer can have, may easily enlarge on what has been laid down 
in the foregoing paragraphs. 
IV. Of clustering Stars, and the Milky-way. 
From quadruple, quintuple, and multiple stars, we are na- 
turally led to a consideration of the vast collections of small 
stars that are profusely scattered over the milky-way. On a 
very slight examination, it will appear that this immense starry 
aggregation is by no means uniform. The stars of which it is 
composed are very unequally scattered, and show evident marks 
of clustering together into many separate allotments. By referring 
to some one of these clustering collections in the heavens, what 
will be said of them will be much better understood, than if we 
were to treat of them merely in a general way. Let us take the 
space between ,G and y Cygni for an example, in which the 
stars are clustering with a kind of division between them, so 
that we may suppose them to be clustering towards two different 
regions. By a computation, founded on observations which 
ascertain the number of stars in different fields of view, it ap- 
pears that our space between (3 and y, taking an average breadth 
of about five degrees of it, contains more than 331 thousand 
stars ; and, admitting them to be clustering two different ways, 
we have 1 63 thousand for each clustering collection. Now, as 
a more particular account of the milky-way will be the subject 
cf a separate paper, I shall only observe, that the above mentioned 
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