ON MATTER AND FORCE. 15 



M. Ampere published his views on heat and 

 light considered as results of the vibratory 

 motion of the imponderable aether. 



The imponderable materialism of the electric 

 and magnetic force commenced with the same 

 stage of ideas regarding heat. 



In 1733, Dufay proposed the idea of two 

 electric fluids, each repelling its own parts or 

 attracting those of the other. Franklin assumed 

 only one fluid, repelling itself and attracting all 

 other matter. In 1803, Dr. Thomas Young, in 

 the Journal of the Royal Institution, vol. i., p. 103, 

 gives his ideas regarding the imponderable 

 material substance which, when present in 

 different bodies, gives rise to electricity. 

 " Perhaps," he says, " some antiphlogistian will 

 soon give us a chemical analysis of the electric 

 fluid. Might I be permitted such a doctrine, 

 it should be that it consists of oxygen and 

 hydrogen combined with caloric only." And 

 in the Annals of Philosophy, new series, vol. ii., 

 p. 196, Sept., 1821, Mr. Faraday says, "There 

 are many arguments in favour of the materiality 

 of electricity, and but few against it ; but still 

 it is only a supposition, and it will be as well to 

 remember, while pursuing the subject of electro- 



