126 B. Galitzine on Radiant Energy. 



present at 

 operation. 



the beginning and end 

 These give 



Ux _ eJi Y 



U 3 ~~ e 2 h 2 ' 



of a 



reve' 



'sible adiabati 



Substitutir 



tg from (25) 



and 



(17), 

 1 



s/h, 

 1 













u 2 











\/h 2 



As h represents the volume (v) of the aether over which 

 the given quantity of energy is distributed, the above equa- 

 tion may be written 



U fy~ v = constant. 



This is a statement which is probably capable of further 

 extension. It expresses the fact that in adiabatic and re- 

 versible processes the quantity of disposible energy is inversely 

 proportional to the cube root of the volume throughout which 

 the energy is distributed. The statement does not involve 

 the absolute temperature, but it really expresses the same 

 principle as the second law of thermodynamics. 



§ 6. Summary of Results. 



1. Bartoli's proof is not admissible in all its details. 



2. The application of the second law of thermodynamics 

 enables us to calculate the pressure of light, as well as the 

 changes of temperature in adiabatic and reversible operations 

 (Boltzmann). 



3. The fourth power of the absolute temperature is directly 

 proportional to the sum of squares of all the electric dis- 

 placements. 



4. Clauses' law of radiation is an immediate consequence 

 of Maxwell's fundamental conceptions. 



5. The transfer of energy to new masses of aether is accom- 

 panied by the expenditure of work in the case of reversible 

 operations. 



6. In the case of adiabatic and reversible processes the 

 amount of disposible energy is inversely proportional to the 

 cube root of the volume throughout which this energy is 

 distributed. 



