90 NOMOS. 



current is passed through the thin wire, and scarcely 

 any or none at all when it is passed through the 

 thick wire, And this difference is very marked, for 

 on passing the current through the thin wire the 

 water in the tube may be made to boil with much 

 activity. 



But it may be asked how do these facts bear 

 upon the seemingly repulsive power of heat ? They 

 bear, we think, very closely, for we can see nothing 

 in this power which is not a natural consequence of 

 electrical action under certain intelligible circum- 

 stances. "What, we ask, is the electrical current ? 

 According to the premises, it is a definite series of 

 chemical changes involving a distinct transfer of 

 matter in space. It is not possible to conceive of 

 ordinary chemical changes without certain changes 

 of place in the elements combining or separating ; 

 and for the same reason it is not possible to conceive 

 of the current without similar changes. The transfer 

 of matter from one electrode to another, or across the 

 fluid with which the battery is charged, are illustra- 

 tions of this fact. What we have first to do, then, 

 is to realise this idea of material transfer as neces- 

 sarily connected with the current. According to 

 the premises, moreover, it is not possible to regard 

 the current as confined to the conductor. On the 

 contrary, it is necessary to regard it as overflowing 

 from the conductor to surrounding parts. Pass it 

 must by one way or another, and, as it will pass 

 most readily through the most open channel, it fol- 

 lows that the amount to which it will overflow will 

 be in direct relation to the inadequacy of the con- 



