17G Velocity of the Elcctr'u- ( %em nt. 



no less than from 15 to 20 wires are fed from the same 

 battery at the same time, it is not an impossible value. 

 It would perhaps be preferable iu such cases to modify the 

 general formulae, by dividing the electro-motive force by 

 the number of lines fed from the battery, which would 

 give R more nearly its true value. But there are so 

 many modifying causes at work in such experiments, that 

 refinement in mathematical computation is not possible, 

 or desirable. 



In case we had a Galvanometer and Rheostat, the values 

 of e and R could be measured directly, and the magnetic 

 force of the current at once ascertained. This is by far 

 preferable, and we hope at some future time to continue 

 the experiments with such apparatus. 



