362 Mr. Faraday [Feb. 27, 



chemical equivalent of power, establishes the principle of the 

 conservation of force also, and at the same time suggests many 

 collateral inquiries whicli have yet to be made and answered, 

 before all that concerns the conservation in this case can be 

 understood. 



This and other instances of chemical action at a distance, carry 

 our inquiring thoughts on from the facts to the physical mode of 

 the exertion of force ; for the qualities which seem located and fixed 

 to certain particles of matter appear at a distance in connexion 

 with particles altogether different. They also lead our thoughts to 

 the conversion of one form of power into another : as for instance, 

 in the heat which the elements of a voltaic pile may either show at 

 the place where they act by their combustion or combination to- 

 gether ; or in the distance, where the electric spark may be ren- 

 dered manifest ; or in the wire or fluids of the different parts of the 

 circuit. 



When we occupy ourselves with the dual forms of power, elec- 

 tricity and magnetism, we find great latitude of assumption ; and 

 necessarily so, for the powers become more and more complicated 

 in their conditions. But still there is no apparent desire to let 

 loose the force of the principle of conservation, even in those cases 

 where the appearance and disappearance of force may seem most 

 evident and striking. Electricity appears when there is consump- 

 tion of no other force than that required for friction ; we do not 

 know how, but we search to know, not being willing to admit that 

 the electric force can arise out of nothing. The two electricities 

 are developed in equal proportions ; and having appeared, we may 

 dispose variously of the influence of one upon successive portions of 

 the other, causing many changes in relation, yet never able to 

 make the sum of the force of one kind in the least degree exceed or 

 come short of the sum of the other. In that necessity of equality, 

 we see another direct proof of the conservation of force, in the 

 midst of a thousand changes that require to be developed in their 

 principles before we can consider this part of science as even mode- 

 rately known to us. 



One assumption with regard to electricity is, that there is an 

 electric fluid rendered evident by excitement in plus and minus 

 proportions. Another assumption is, that there are two fluids of 

 electricity, each particle of each repelling all particles like itself, 

 and attracting all particles of the other kind always, and with a 

 force proportionate to the inverse square of the distance, being so 

 far analogous to the definition of gravity. This hypothesis is 

 antagonistic to the law of the conservation of force, and open to all 

 the objections that have been, or may be, made against the ordinary 

 definition of gravity. Another assumption is, that each particle 

 of the two electricities has a given amount of power, and can only 

 attract contrary particles with the sum of that amount, acting upon 

 each of two with only half the power it could in like circumstances 



