FEB 17 



THE LAW OF CONTRACTION OF GASEOUS 

 NEBULAE. 



Francis E. Niphek. 



In the discussion which follows it will be assumed that a 

 nebulous mass of spherical form, is gravitating towards a 

 central nucleus, and that the gas follows the law 



jPv=CT. (1) 



At any point in the mass, the heat dQ, added to unit mass 

 of volume v, under increasing pressure is, 



dQ=C\dT+Fdv (2) 



Let it be assumed that when thus subject to compression 

 due to gravitation, the relation between pressure and specific 

 volume is represented by the equation 



Pv- = j^=A. (3) 



It is required to find the value of n. Eliminating P in ( 1 ) 

 and (3), 



C 



A^^ 



By differentiation 



C 

 A{2 — n) 



Combining this equation with (3) 



C 

 Pdv = -^ dT. (.\ 



Hence if this quantity be expressed in heat units, the spe- 

 cific heat of the gas will be 



(143) 



