Franklin, Dufay and Ampere. 473 



41. When the oppositel)' polarizing waves, generated by 

 friction as above described, are by means of a conducting 

 communication transmitted to the surfaces of a coated pane, 

 the two different portions of the electro-aether there existing 

 are severally polarized in opposite ways, one being endowed 

 with the properties usually called vitreous or positive, the 

 other with those usually called resinous or negative. In fact, 

 the two polarized atmospheres thus created may be conveni- 

 ently designated as the "/too electricities" and alluded to in 

 the language heretofore employed in treating of phaenomena, 

 agreeably to the hypothesis which assumes the existence of 

 heterogeneous fluids, instead of heterogeneous polarities. 



42. Of course it will follow that the oppositely polarized 

 aethereal atmospheres thus produced, one on each surface of 

 the electric which keeps them apart, must exercise towards 

 each other an attraction perfectly analogous to that which 

 has been supposed to be exercised by the imaginary hetero- 

 geneous electric fluids of Dufay. The electro-aether* being 

 elastic, a condensation over each of the charged surfaces pro- 

 portionable to the attractive force must ensue ; while over 

 the surface of an electrified conductor, the similarly polarized 

 atoms not being attracted by those in an oppositely polarized 

 atmosphere beneath the surface, tend, by their reciprocally 

 repulsive reagency, to exist further apart than in a neutral 

 state. Hence the electro-aether, as it exists over the surface 

 of an insulated conductor, is rendered rarer, while, as existing 

 over the surfaces of charged panes or Leyden jars, it must be 

 in a state of condensationf. And consequently, while the 

 space perceptibly electrified by the charge of a conductor, for 

 equal areas and charging power, is much more extensive than 

 the space in which the charge of a coated pane is perceptible, 

 the striking distance being likewise much greater; yet upon 

 any body successively subjected to a discharge from each, the 

 effect will be more potent when produced by means of the 

 pane. 



Ignition, Electroltjsis and Magnetism, Secondary Effects of 

 Frictional Dischaigcs ,• or, in other words, of Polariziyig 

 Electro-ccthereal Waves. 



4,3. In proportion as a wire is small in comparison with 

 the charge which it may be made the means of neutralizing, 

 the conducting power seems to be more dependent on the 



* As the word aether is used in various senses, the syllables "electro^' 

 being prefixed, serve to designate that which is intended. 



f See my cuniinunication on " Free Kkclricilii" in Silliman's American 

 Journal of Science, vol. iii., New Series, Number for May 1847. 



