Lines of Force

—In any ‘“‘field” such as that produced around and inside a coil of wire through which a current flows, or between the poles of any magnet either electrical or permanent, there are invisible lines of force which arrange themselves in a definite shape around and between the poles, and if they be cut in any way by moving a wire acro them, a current is produced in the wire and this current depends largely upon the number of these lines of force which are cut per second. It makes no difference whether the wire be held stationary and the magnet and its field moved, or whether the wire itself is moved and the field is stationar The result is the same as far as producing current is concerned. The utilization of this principle is the basis upon which the mechanical producers of electricity, such as dynamos and magnetos, are made.