4 Second Letter from Dr. Hare to Prof. Faraday. 



imity. Agreeably to my view, the action is confined to the elec- 

 trical accumulation in the sphere A. Between the electricity 

 accumulated in this sphere, and that existing in, or about, the 

 intervening ponderable particles, there may be a reaction ; but 

 evidently these particles are as inactive as are the steps of a lad- 

 der in the scaling of a wall. 



Suppose a powerful magnet to be so curved as to have the 

 terminating polar surfaces parallel, and leaving between them an 

 interval of some inches. Place between these surfaces, a number 

 of short pieces of soft iron wire. These would of course be mag- 

 netized, and would arrange themselves in rows, the north and 

 south poles becoming contiguous. Would this be a sufficient 

 reason for saying that the inductive influence of the magnetic 

 poles was an action of the contiguous wires ? Would not the 

 phenomena be the consequence of an affection of the contiguous 

 pieces of wire, not of their action ? 



As respects the word charge, I am not aware that I have 

 been in the habit of attaching any erroneous meaning to it, as 

 your efforts to define it in paragraph iii would imply. I have 

 been accustomed to restrict the use of it to the case which you 

 distinguish as an inductive charge, illustrated by that of the Ley- 

 . den jar. To designate the states of the conductors of a machine, 

 I have almost always employed the words excited or excitement. 

 In my text-book, these words are used to designate the state of 

 glass or resin electrified by friction, while that of coated surfaces, 

 whether panes or jars, inductively electrified, has been designated 

 by the words charge or charged. 



I understood the word contiguous to imply contact, or con- 

 tiguity, where, as it seems that it was intended by you to con- 

 vey the idea of proximity. In the last mentioned sense it is not 

 inconsistent with the idea of an action at the distance of half an 

 inch : but by admitting the word contiguous to be ill chosen, you 

 have, with great candor, furnished me with an apology for having 

 mistaken your meaning. 



Any inductive action which does not exist at sensible dis- 

 tances, (xx,) you attribute to ordinary induction, considering the 

 case of induction through a vacuum as an extraordinary case of 

 induction. To me it appears that the induction must be the same 

 in both cases, and that the circumstances under which it acts, are 



