346 D. Trowbridge on the Nebular Hypothesis. 
again we are reduced to conjecture. We cannot determine, 
our conceptions, but rather to have been an amorphous mass, 
like the clouds of vapor which float in our atmosphere. If we 
could suppose this great nebulous mass to have been symmetrical 
in form and homogeneous in structure, in the process of cooling 
and condensation there would be little probability of its gene- 
i i i uy under such conditions 
the matter would condense into a sphere. But we have not the 
remotest evidence—nay, all our evidence is to the contrary— 
that the original nebulous mass was homogeneous. It is a very 
difficult thing to find even a small amount of matter perfectly 
homogeneous. We must, therefore, conclude that the probability 
against the homogeneity of the original gaseous mass, is many 
millions to one in favor of it. Even if it were originally per- 
fectly homogeneous, but of irregular shape, the attraction of 
gravitation, and the other forces of nature which acted upon it, 
would soon * cause it to become heterogeneous in its constitution. 
5. Again, if we suppose the original fluid mass to have been 
of equilibrium;* and such a change would generate a motion 
tation about one or more axes, It is highly probable— 
caused by the form of the body, and the heterogeneous nature 
* In saying that such a result would be soon reached, it must not be su 
that we mean “soon” accordi 
s ing to our ideas of time. A million of years might 
_ ® It mast not be supposed that because the conditions of equilibrium are not sat- 
will be a “ breaking up” and a separation into ae masses, but 
; Bip es 
