346 Dr. Faraday's Thoughts on Ray-vibrations. 



supposed to exist only by these forces, and where they are it 

 is. The consideration of matter under this view gradually 

 led me to look at the lines of force as being perhaps the seat 

 of the vibrations of radiant phaenomena. 



Another consideration bearing conjointly on the hypotheti- 

 cal view both of matter and radiation, arises from the compari- 

 son of the velocities with which the radiant action and certain 

 powers of matter are transmitted. The velocity of light through 

 space is about 190,000 miles in a second ; the velocity of elec- 

 tricity is, by the experiments of Wheatstone, shown to be as 

 great as this, if not greater : the light is supposed to be trans- 

 mitted by vibrations through an aether which is, so to speak, 

 destitute of gravitation, but infinite in elasticity ; the electri- 

 city is transmitted through a small metallic wire, and is often 

 viewed as transmitted by vibrations also. That the electric 

 transference depends on the forces or powers of the matter of 

 the wire can hardly be doubted, when we consider the differ- 

 ent conductibility of the various metallic and other bodies; 

 the means of affecting it by heat or cold ; the way in which 

 conducting bodies by combination enter into the constitution 

 of non-conducting substances, and the contrary ; and the ac- 

 tual existence of one elementary body, carbon, both in the 

 conducting and non-conducting state. The power of electric 

 conduction (being a transmission of force equal in velocity to 

 that of light) appears to be tied up in and dependent upon 

 the properties of the matter, and is, as it were, existent in 

 them. 



I suppose we may compare together the matter of the aether 

 and ordinary matter (as, for instance, the copper of the wire 

 through which the electricity is conducted), and consider 

 them as alike in their essential constitution ; i. e. either as 

 both composed of little nuclei, considered in the abstract as 

 matter, and of force or power associated with these nuclei, or 

 else both consisting of mere centres of force, according to 

 Boscovich's theory and the view put forth in my speculation ; 

 for there is no reason to assume that the nuclei are more re- 

 quisite in the one case than in the other. It is true that the 

 copper gravitates and the aether does not, and that therefore the 

 copper is ponderable and the aether is not ; but that cannot 

 indicate the presence of nuclei in the copper more than in the 

 aether, for of all the powers of matter gravitation is the one in 

 which the force extends to the greatest possible distance from 

 the supposed nucleus, being infinite in relation to the size of 

 the latter, and reducing that nucleus to a mere centre of force. 

 The smallest atom of matter on the earth acts directly on the 

 smallest atom of matter in the sun, though they are 95,000,000 



