Masterpieces of Science 



cults are employed, the first a long circuit through 

 which the electricity is sent to the distant station 

 to bring into action the second, a short one, in 

 which is the local battery and magnet for work- 

 ing the machine. In order to give projectile 

 force sufficient to send the power to a distance, 

 it is necessary to use an intensity battery in the 

 long circuit, and in connection with this, at 

 the distant station, a magnet surrounded with 

 many turns of one long wire must be employed 

 to receive and multiply the effect of the current 

 enfeebled by its transmission through the long 

 conductor. In the local or short circuit either 

 an intensity or a quantity magnet may be em- 

 ployed. If the first be used, then with it a com- 

 pound battery will be required; and, therefore 

 on account of the increased resistance due to 

 the greater quantity of acid, a less amount of 

 work will be performed by a given amount of 

 material; and, consequently, though, this arrange- 

 ment is practicable it is by no means economical. 

 In my original paper I state that the advantages 

 of a greater conducting power, from using several 

 wires in the quantity magnet, may, in a less de- 

 gree, be obtained by substituting for them one 

 large wire; but in this case, on account of the 

 greater obliquity of the spires and other causes, 

 the magnetic effect would be less. In accordance 

 with these principles, the receiving magnet, or 

 that which is introduced into the long circuit, 

 consists of a horse-shoe magnet surrounded with 

 many hundred turns of a single long wire, and 

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