Nebular Theory. — Mislockles. 235 
Sun and »tlio jilanets are said to have been formed. Conse- 
qucntlv the solar system in its present state represents the mat- 
ter which composed the original nebula. If we, then, should 
find bv thorough investigation, that the Sun and the plan- 
ets together contain, say about only half of the matter which 
the original nebula contained, then the theoretical supposition 
would be a miscralile failure. The question is : What was the 
density of the nebular matter? In order to clear this point, we 
must know the size and cubic contents of the nebula and there- 
bv its weight ; and- then compare this weight with the weight 
of the Sun and the ])Ianets together, which is known. 
In the first place, then, it seems proper for us to inquire 
whether, if the Sun and planets were dissolved into atoms 
and spread out evenly in a space having a diameter of 5000 
million miles it would constitute a mass dense enough to be 
heated by the friction of its own matter and having depres- 
sions at the poles and expansion at the equator, together with 
an immense centrifugal force, sufficient to throw oil' rings? 
Francis P. Leavenworth, professor of astronomy in the Uni 
versity of Minnesota, told me, that one of his students had 
worked on this problem and figured out, that if -our solar sys- 
tem were dissolved into atoms and spread out evenly in a 
comparatively spherical space, filling the orbit of Neptune, these 
atoms would be hovering about, separated from one another 
bv large distances. Professor Leavenworth himself said that 
this was no doubt correct. But if that is so, which it evidently 
is, what, then, becomes of the attribute, which the theorists 
have ascribed to this misty mass, which would be no mist, but 
rarer than high mountain air? It follows, also, that it would 
have neither equator nor poles, neither rotation nor centrifugal 
force, and far less would it throw off any rings! 
We notice at once, that the assumption Avith regard to the 
size of the nebula is just as erroneous as we have before found 
the assumption with regard to its rotation. Let us, however, at 
this point, consider the nebula from another point of view. 
As a consequence of the attributes ascribed to it. such as 
heat, centrifugal force, expanded equator, and flattened poles, 
it ought to have possessed a considerable density. Let us sup- 
pose, however, that it had the density of common air only, a 
supposition which every one must admit to be fair. In order 
