18 CKOONIAN LECTURES 



again to be employed in a reverse direction 

 when it is set at liberty. (Faraday, Eesearches 

 in Chemistry, p. 454.) 



If it were possible to take the ultimate atom 

 of any one of the elements, we should find that 

 the chemical force which constitutes and de- 

 termines its nature would be absolutely in- 

 separable from the matter of which the element 

 consists. 



For example, the ultimate atom of carbon 

 would have the same kind of force as any mass 

 of carbon, and it would differ in kind, and 

 always from the ultimate atom of any other 

 element, because of the peculiarity of its force. 

 If the chemical force could be separated from 

 the atom of carbon, the matter might cease to 

 be carbon, and might become some other ele- 

 ment, and the transmutation of metals might 

 then be possible. 



The union, also, between matter and gravity 

 is just as inseparable as the union between 

 matter and chemical force. Matter without 

 weight is not matter at all ; the weight belongs 

 to the matter, and cannot be taken from it. 

 'The gravity can no more be destroyed than the 

 matter itself can be destroyed. However small 



