Scientific Lectures. ]81 



ated with — something. It goes through your clothes, it penetrates 

 your bodies, and saturates your brains. It must do so ; something 

 must be all around us and within us, for surely out of nothing I can- 

 not evolve something — a current of electricity ; and a current of 

 electricity is surely something ; it is everything, physically considered ; 

 for it is a force, and will do work ; it is a power ; the product of the 

 motion of the wire; for, without its motion, the current will not be 

 produced, and, whenever the current is produced, a break is placed on 

 the motion of the wire, it requiring more force to turn the ring when 

 the current traverses it than when it does not. In other words, part 

 of the force which urges the rotation of the wire disappears in it, but 

 reappears in the motion of that needle, and in the electric wave 

 which traverses the galvanometer and these conducting wires. " But," 

 as Faraday observes, in speaking of these phenomena, " mere motion 

 would not generate a relation which had not a foundation in the exist- 

 ence of some previous state ; and, therefore, the quiescent metal [the 

 ring] must be in some relation to the active center of force " [the 

 Magnet]. " He here," says Tyndall,* " touches the core of the whole 

 question ; and when we can state the condition into which the conduct- 

 ing wire is thrown before it is moved, we shall then be in a position 

 to understand the physical constitution of the electric current gene- 

 rated by its motion." Yet, is there not something existing in and around 

 the wire "before it is moved," and through which, in moving, the 

 wire experiences a resistance ? And does not the magnet either send 

 out this something, or exert on something previously existing around 

 it, a peculiar action, which action constitutes the propagation of its 

 distant effects? Surely, in the language of Newton, "that one body 

 may act upon another at a distance, through a vacuum, and without 

 the mediation of anything else, by and through which this action and 

 force may be conveyed from one to another, is to me so great an 

 absurdity that I believe no man who has, in philosophical matters, a 

 competent faculty of thinking, can ever fall into it. Gravity must be 

 caused by an agent acting constantly, according to certain laws; but, 

 whether this agent be material or immaterial, I have left to the con- 

 sideration of my readers." Yes, the whole of this building and the 

 neighboring streets are permeated with something — immaterial or 

 material, I know not — emanating from this magnet, or acted on by it. 

 The street cars have run through it while I have been lecturing, and 

 pedestrians have cut it with their legs in walking. What it is, I know 

 not ; we call it magnetism. 



* Faraday as a Discoverer. Amer. ed., p. 132. 



