108 Dr. J. E. Mills on the Relation oj 



certainly does, possess a vast store o£ energy. Its store o£ 

 energy is perhaps comparable to that possessed by radium. 



In what form does the 67,300 calories o£ energy possessed 

 by the 34' 78 c.c. of hydrogen and oxygen at —273° C. 

 exist ? If the same mechanical laws which govern larger 

 masses of matter and energy at higher temperatures apply 

 to the hydrogen and oxygen at —273 C, then a stable 

 system could not exist if all of the energy were kinetic, or if 

 all of the energy were potential, but some portion of the 

 energy must be potential and some portion must be kinetic. 

 There has never been the slightest evidence produced to show 

 that these mechanical laws do cease to hold at —273° C, or 

 with small subdivisions of mass, and therefore I think it 

 probable that at —273° C. the small particles — atoms if you 

 please to call them so — of hydrogen and oxygen are in 

 exceedingly rapid motion around their common centre of mass. 



Considering the two bodies under discussion it seems clear 

 that when they are moving in circular orbits around their 

 common centre of mass, their orbital velocity does not con- 

 stitute " temperature " motion. Two particles in such motion 

 would constitute a stable system such as a hydrogen, H 2 , or 

 oxygen, 2 , molecule. The temperature of the system would 

 be zero if the centre of mass were stationary. 



20. If w r e attempt to consider how three bodies attain and 

 maintain a system in stable equilibrium under the assumed 

 law of force — the gravitational law — we find that mathema- 

 tical analysis has as yet failed to completely solve the problem. 

 And yet the energy relations involved can hardly be supposed 

 greatly different from" those already discussed for two bodies. 

 It would seem fairly certain that each body in order to form 

 a stable system would have to surrender some of the energy 

 which it would acquire from the aether in coming into its 

 orbital position from an infinite distance, and would retain 

 some of this energy. The problem of four bodies is yet 

 greatly more complicated, and it will always be impossible 

 for mathematical analysis to follow n bodies through their 

 mutual individual actions and orbits. 



While leaving the safe ground of mathematical analysis 

 we are yet experimentally certain that n bodies in coming 

 together do give out a certain amount of energy, and I have 

 shown in the papers cited* that the energy given out ("lost") 

 by these n bodies on coming together follows exactly the 

 same law shown to hold for two bodies, namely : — 



E M . s = constant (19) 



* See the eighth and ninth articles in the Journ. Phys. Ghera. or the 

 article in the Phil, Mag. 



