EXPERIMENTS WITH THE TOPLER MACHINE. 129 



The explanation is as follows. When a Topler ma- 

 chine is in operation, there is a strong attraction be- 

 tween the plates, the result of induction from the 

 opposite electric states of the parts in proximity. This 

 attraction which constantly increases up to the instant 

 of discharge, acts as a resisting force which must be 

 overcome by the force used to rotate the plate. Now, 

 when the two machines are connected, this electric 

 force is transmitted to the secondary, where, having no 

 mechanical force to oppose it, as in the primary, 

 it causes the rotation of the plate in the opposite 

 direction. 



Thus the mechanical force in the primary is trans- 

 muted into electric force, passes <fver to the secondary 

 and reproduces mechanical force ; the force applied to 

 the primary being expended in the secondary. 



The apparatus thus becomes a scientific bank, with 

 its receiving and paying tellers. But nature is a 

 shrewd banker, and always exacts full discount ; hence 

 the mechanical energy, paid in to the primary, is dis- 

 counted by friction, leakage, and heat; so that the 

 remaining energy may not be sufficient to start the 

 plate of the secondary into rotation without an ad- 

 ditional payment. 



The sliding electrodes in the secondary machine may 

 l)e adjusted to produce the electric discharge with spark 

 and snap, instead of the mechanical rotation of the 

 plate ; thus illustrating the transmutation of force, at 

 will, from mechanjcal to electric, and from electric 

 either back again to mechanical, or to the heat, light, 

 and sound of the electric discharge. 



SOUECE OF ELECTRIC SUPPLY OF THE TOPLEK MA- 

 CHINE. The earth, the machine itself, and the air are 



