2 THE THEORY OF IONS 



matter at a distance ; they constantly encounter 

 and rebound from one another, some moving with 

 a greater or less speed than others, but all having 

 an average velocity. In these encounters there is 

 no loss of energy so long as the temperature remains 

 the same, for every action is balanced by an equal 

 and contrary reaction ; but any change of tempera- 

 ture causes a change of velocity, with increased speed 

 there is increased heat and some of the energy 

 then radiates into space. This vibratory motion of 

 the smallest particles of matter is regarded by many 

 authorities as the fundamental exhibition of the 

 energy stored up in matter ; and attraction, gravity, 

 chemical action, magnetism, electricity, heat and 

 light are regarded as being modifications of the 

 primitive inherent force. 



According to the brilliant theory of J. C. Vogt, 

 spate is filled with a fundamental force, and its 

 activity is shown by a tendency to the condensation 

 of matter, which produces infinitesimal centres of 

 attraction. In this theory of condensation, however, 

 the separate particles are credited with sensation 

 and inclination, a will-movement of the simplest 

 form. Centres of disturbance occur which posi- 

 tively exceed the mean tendency to condensation, 

 whence are formed the ponderable matter of bodies ; 

 centres of disturbance also occur which negatively 

 fall below the mean power of condensation, and 

 these form the ether or imponderable matter. 

 Positive or ponderable matter, ever straining to com- 

 plete the process of condensation, collects an enor- 

 mous amount of potential energy ; negative or im- 

 ponderable matter (the ether) offers a perpetual 



