414 Dr. Faraday on the Physical Character of 



paramagnetic bodies is dismissed, then there is no effect of 

 attraction or repulsion, or any ordinary magnetic result produced. 

 The phamoniena may all very fairly be looked upon as purely 

 electrical, for they are such in character ; and if they coincide 

 with magnetic actions (which is no doubt the case), it is pro- 

 bably because the two actions are one. But being considered 

 as electrical actions, they convey a different idea of the condition 

 of the field where they occur, to that involved in the thought of 

 magnetic action at a distance. When a copper wire is placed in 

 the neighbourhood of a bar-magnet, it does not, as far as we are 

 aware (by the evidence of a magnetic needle or other means), 

 disturb in the least degree the disposition of the magnetic forces, 

 either in itself or in surrounding space. When it is moved across 

 the lines of force, a current of electricity is developed in it, or 

 tends to be developed; and there is every reason to believe, that 

 if we could employ a perfect conductor, and obtain a perfect 

 result, it would be the full equivalent to the force, electric or 

 magnetic, which is exerted in the place occupied by the con- 

 ductor. But, as I have elsewhere observed (3172.), this cur- 

 rent, having its full and equivalent relation to the magnetic 

 force, can hardly be conceived of as having its entire foundation 

 in the mere fact of motion. The motion of an external body, 

 otherwise physically indifferent, and having no relation to the 

 magnet, could not beget a physical relation such as that which 

 the moving wire presents. There must, I think, be a previous 

 state, a state of tension or a static state, as regards the wire, 

 which, when motion is superadded, produces the dynamic state 

 or current of electricity. This state would constitute and give 

 a physical existence to the lines of magnetic force, and permit 

 the occurrence of curvature or its equivalent external relation of 

 poles, and also the various other conditions, which I conceive 

 are incompatible with mere action at a distance, and which yet 

 do exist amongst magnetic phenomena. 



3271. All the phaenomena of the moving wire seem to me to 

 show the physical existence of an atmosphere of power about a 

 magnet, which, as the power is antithetical, and marked in its 

 direction by the lines of magnetic force, may be considered as 

 disposed in sphondyloids, determined by the lines, or rather 

 shells of force*. As the wire intersects the lines within a given 



* The lines of magnetic force have been already denned (30/1.). They 

 have also been traced, as I think, and shown to be closed curves passing 

 in one part of their course through the magnet to which they belong, and 

 in the other part through space (311/.). If, in the case of a straight bar- 

 magnet, any one of these lines, E, be considered as revolving round the axis 

 of the magnet, it will describe a surface; and as the line itself is a closed 

 curve, the surface will form a tube round the axis and inclose a solid form. 

 Another line of force, F, will produce a similar result. The sphondyloid 



