THE PROBLEM OF PARTITION OF ENERGY, 

 ESPECIALLY IN RADIATION 



1. AGREEMENT seems to be nearly as remote as ever regarding 

 the manner in which deviation from the condition of equi- 

 partition of energy amongst the various freedoms of an 

 apparently conservative system, in apparent equilibrium, is 

 brought about. The well-known discrepancies which occur 

 between the actual ratios of the principal specific heats of 

 gases and their theoretical ratios calculated, on the assumption 

 of equipartition, from the multiplicity of freedoms which 

 radiational phenomena make evident in the case of even 

 monatomic gases, make the fact of extreme deviation from 

 equipartition very evident. 



It is fully recognised that, in many very special cases, 

 dynamical freedoms may be entirely inoperative. So one way 

 of avoiding the difficulty consists in asserting that the special 

 freedoms made evident in radiational phenomena are in- 

 operative in ordinary thermal phenomena. Such a mode is 

 unsatisfactory apart from the specification, by analogy at 

 least, of an appropriate mechanism ; for the doctrine of 

 equipartition does not permit mere partial inoperativeness 

 the inoperativeness must be total. Another method, adopted 

 by Jeans, consists in regarding a final condition of statistical 

 equilibrium between matter and ether, with consequent 

 equipartition of energy amongst the freedoms, as unattainable 

 in finite time ; so that the practical ' steady ' conditions, 

 which subsist in experimental tests, and are the result of a 

 steady supply of energy in one form compensating an equal 

 steady loss in an other form, give rise to that non-equable 



