152 Trans. Acad. Sci. of St. Louis. 



computes the specific heat of gravitational contraction as 

 follows : — 



By a well-known equation 



C C 



dQ=jf vdP + jf Pdv. 



From the equation of a perfect gas, 



1 1 



dT =jj vdP + jj Pdv. 



Hence for the specific heat 



From eq. (3) 



dQ _ ^> P + ^^ t; 



1/T~ dP dv_ 



~P '^ V 



dP _ dv 



P ~ V 



Op 

 where « = yy- = 1.41, 



4 



Assuming " = - Eitter obtains 



o 



For hydrogen Cp = 3.409, which gives 



dO 

 ^^^-0.547. 



(29). 



This equation in (29) gives 



dQ Cp — nC^ CpIk — 7i\ 



dT= 1-n -Tlr=rJ- (30) 



||:=_ 0.16312 CV (31). 



