6 THE ORIGIN OF MAN 



ally existing in a diffuse state, through gravita- 

 tion attraction. Or in other words these atoms 

 united and formed different masses. Another 

 essential part of this hypothesis was the concep- 

 tion of a nebula as a unit body, distended by heat, 

 and revolving as a single mass. In this nebular 

 hypothesis we have been dealing with only one 

 force, namely attraction. In the nineteenth cen- 

 tury evidences of another force in our stellar uni- 

 verse became prominent, that force being repul- 

 sion. 



Let us then conceive that these atoms which 

 we have distributed through space to have become 

 united into one mass. Then let us suppose that 

 matter was thrown out from this mass or sun, and 

 assuming the form of a spiral nebula, not as un- 

 der the nebular hypothesis, as being the residue 

 left behind from the primal condensation of mat- 

 ter into a sun. The form of the nebula was main- 

 tained, let us suppose, through the motion of its 

 particles moving in orbits, and not by the resist- 



