268 DR. FARADAY'S EXPERIMENTAL RESEARCHES IN ELECTRICITY. (SERIES XIV.) 



induct outwards through the air, producing in that outer coating what is sometimes 

 called, though I think very improperly, free charge. If a small Leyden jar be con- 

 verted into that form of apparatus usually known by the name of the electric well, 

 it will illustrate this action very completely. 



1684. The terms free charge and dissimulated electricity coxwey therefore erroneous 

 notions if they are meant to imply any difference as to the mode or kind of action. The 

 charge upon an insulated conductor in the middle of a room is in the same relation 

 to the walls of that room as the charge upon the inner coating of a Leyden jar is to 

 the outer coating of the same jar. The one is not more free or more dissimulated 

 than the other, and when sometimes we make electricity appear where it was not evi- 

 dent before, as upon the outside of a charged jar when, after insulating it, we touch 

 the inner coating, it is only because we divert more or less of the inductive force from 

 one direction into another ; for not the slightest change is in such circumstances im- 

 pressed upon the character or action of the force. 



1685. Having given this general theoretical view, I will now notice particular 

 points relating to the nature of the assumed electric polarity of the insulating dielec- 

 tric particles. 



1686. The polar state may be considered in common induction as a forced state, 

 the particles tending to return to their normal condition. It may probably be raised 

 to a very high degree by approximation of the inductric and inducteous bodies or by 

 other circumstances; and the phenomena of electrolyzation (861. 1652. 1706) seem 

 to imply that the proportion of power which can thus be accumulated on a single 

 particle is enormous. Hereafter we may be able to compare corpuscular forces, as 

 those of gravity, cohesion, electricity, and chemical affinity, and in some way or other 

 from their effects deduce their relative equivalents ; at present we are not able to do 

 so, but there seems no reason to doubt that their electrical, which are at the same 

 time their chemical, forces (891. 918.) will be by far the most energetic. 



1687. I do not consider the powers when developed by the polarization as limited 

 to two distinct points or spots on the surface of each particle to be considered as the 

 poles of an axis, but as resident on large portions of that surface, as they are upon 

 the surface of a conductor of sensible size when it is thrown into a polar state. But 

 it is very probable, notwithstanding, that the particles of different bodies may present 

 specific differences in this respect, the powers not being equally diffused though equal 

 in quantity ; other circumstances also, as form and quality, giving to each a peculiar 

 polar relation. It is perhaps to the existence of some such differences as these that 

 we may attribute the specific actions of the different dielectrics in relation to discharge 

 (1394. 1508.). Thus with respect to oxygen and nitrogen singular contrasts were 

 presented when spark and brush discharge were made to take place in these gases, as 

 maybe seen by reference to the Table in paragraph 1518 of the Thirteenth Series ; for 



