Voltaic Induction. 29 



tides. In unmagnetic matter, their developement is but temporary, 

 and can be sustained only by a constant repetition of the inductive 

 process. 



One of the most remarkable circumstances attending the genera- 

 tion of voltaic currents, whether caused by an artificial magnet or a 

 galvanic battery, is that motion is absolutely necessary for the effect. 

 The motion proceeding from the rotation is quite insufficient, and that 

 connected with the lateral distribution of the magnetic circles, along 

 the circuit wire, is calculated to generate counter currents. What fact 

 could be brought forward more opposed to the supposition that the vol- 

 taic fluid, considering it as common electricity, produces the effect by 

 induction ? No analogy sustains it, and the little probability attending 

 it must disappear, if it can be shown that the result arises from mag- 

 netic induction singly. Although the rotating magnetic poles of a 

 magnet or battery, are not capable without the aid of motion, of 

 generating voltaic currents in steel, they readily produce the mag- 

 netic forces; and hence, it would follow that either the latter do 

 not depend upon the same conditions as the former, and are, there- 

 fore, capable of a separate existence, or that the voltaic currents 

 thus generated without the motion of the steel, at once pass to the 

 particles and confine themselves exclusively to their limits. The 

 latter supposition is the less probable because there is not the slight- 

 est evidence that voltaic currents can be produced under like circum- 

 stances, in other metals, for all of which motion is absolutely neces- 

 sary, and when generated the circulation can be made to pass into 

 the galvanometer. There is, obviously some great peculiarity, char- 

 acteristic of iron and its magnetic compounds, which thus enables it 

 to undergo the process of induction by the unaided revolutions of the 

 magnetic forces, in a magnet placed close to it, and which cannot be 

 accomplished with other metals unless they are moved during the ex- 

 posure. Without wishing to offer any positive opinion of the cause, 

 it may be suggested that perhaps the forces, proceeding from a mag- 

 net, upon passing into the steel, suffer a deflection, as the rays of 

 light do when they enter transparent media, and which enables them 

 to act more powerfully upon one side of every particle composing a 

 layer of metal, than upon the opposite one. The result might be, 

 that free polar forces would be put in motion, at the points of all 

 the particles most directly opposing this deflection. 



Thus, let N, fig. 3, represent the north pole of a magnet and yx, 

 yXy &c. its polar forces acting in curves, like those of the electro- 



