Nipher — The Latv of Contraction of Gaseous Nebulae. 157 



2CT 



g=1.22-^ (18)'. 



Equations (19) to (22) become 



0.636 ]\Pk ,-,fj„ 



P=- ^ (19) 



(21)' 



Equation (23) also becomes (see (26) ), 



Pv^ = 1.034 ^•J/^ . (23)' 



Equations (24) and (25) need not be rewritten. 

 The work done in compressing a mass 3f, from an infinite 

 volume to a sphere having a radius P is 



Tr=47r \RU^dR. 



r [rU^c 



The value of P being obtained from (19) this integral is 



^^ 4-3h MVc 



n 2R ^ ^ 



= 0.636 . ^^ ^ 

 2R 



If an isothermal distribution of temperature were possible 

 during the compression, n would be unity and the coefficient 



