214 SPECULATIVE SCIENCE 



the intermediate and possibly constituent medium may be 

 arrived at. Then the motion of planets and music of the spheres 

 will be neglected for a while in admiration of the maze in which 

 the tiny atoms turn. Those who doubt the possibility of this 

 achievement should read the writings of Thomson, Clausius, 

 Rankine, and Clerk Maxwell. They will there gain some insight 

 into what is meant by an explanation of such things as heat, 

 electricity, and magnetism, as caused by the motion of matter, 

 ponderable or imponderable. They will also perceive the vast 

 difference between the old hazy speculations and the endeavours 

 of modern science. Yet when we have found a mechanical 

 theory by which the phenomena of inorganic matter can be 

 mathematically deduced from the motion of materials endowed 

 with a few simple properties, we must not forget that Democri- 

 tus, Leucippus, and Epicurus began the work, and we may even 

 now recognise their merits, and acknowledge Lucretius not only 

 as a great poet, but as the clear expositor of a very remarkable 

 theory of the constitution of matter, though we must admit that 

 he failed in his bolder attempts to abolish the gods, and dis- 

 pense with creation, or even to reconcile universal causation with 

 free-will. 



