A KINETIC THEORY OF MATTER. 231 



energy into the shape of translational energy 

 in the course of a collision, and I think it rigor- 

 ously demonstrable that the whole translational 

 energy must ultimately become transformed into 

 vibrational energy of higher and higher nodal 

 subdivisions if each molecule is a continuous 

 elastic solid. Let us, then, leave the kinetic 

 theory of gases for a time with this difficulty 

 unsolved in the hope that we or others after us 

 may return to it, armed with more knowledge of 

 the properties of matter, and with sharper mathe- 

 matical weapons to cut through the barrier 

 which at present hides from us any view of the 

 molecule itself, and of the effects, other than 

 mere change of translational motion, which it 

 experiences in collision. 



To explain the elasticity of a gas was the 

 primary object of the kinetic theory of gases. This 

 object is only attainable by the assumption of an 

 elasticity more complex in character, and more 

 difficult of explanation, than the elasticity of 

 gases the elasticity of a solid. Thus, even if 

 the fatal fault in the theory, to which I have 



