342 CARNEGIE INSTITUTION OF WASHINGTON. 



in this and other connections are elinainated if we adopt the view that the 

 radiation formula is fundamental in the form 



where h and a are constants, and that the approximate laws according to which 

 molecules are acted upon by the fields in which they exist result in the average 

 energy of a molecule situated in a field of radiation becoming Lim;,=oX*£^ /8t 

 i. e., in this case, Th/a. This law becomes readily verified for the special case 

 of an electron, and if its truth can be extended to molecules we see that it is 

 not because R is the gas-constant that it occurs in the radiation formula, but 



-prp 



rather that the gas-molecule moves with the average energy — , per degree 



of freedom because this constant is involved in the radiation formula. On an 

 extension of the above view, it becomes apparent that the form of ^x as a 

 function of the temperature is largely determined by the fact that we 

 measure the temperature in such a way that this must be the case. 



