ON MATTER AND FORCE. 91 



by looking for its effect as the most peculiar of 

 all the motions of which matter is capable. 

 This must be able to arise from other motions 

 and be able to give rise to other motions ; and 

 its cause must be altogether as incapable of 

 destruction and creation as the abiological 

 forces themselves. 



It may well be said, what can be the nature 

 of this motion ? how can it be understood ? The 

 answer must be the same as that which we 

 must give even now regarding the nature of 

 the motion of the simple or compound atoms of 

 matter which we call electricity or magnetism, 

 or even light or heat. 



How many among us at present have a clear 

 idea of the motion of the simple molecules of 

 matter which we call heat, or even gravitation 

 and crystallisation ? Whilst we are unable to 

 grasp the marvellously complex double polar 

 motion of compound molecules which consti- 

 tutes electricity, can we expect to be able to 

 form an idea of the most complex of all the 

 motions of matter from which the mind turns 

 away to the image of some aerial or setherial 

 spirit, with large wings and larger powers ; or 

 rests satisfied with an imponderable gaseous or 



