J 821.] Magnetic Phenomena produced by Electricity. 87 



three, four, or more wires, forming part of the same circuit 

 parallel to each other in the same plane, or in different planes, 

 it could hardly be doubted that each wire, and the space around 

 it, would become magnetic in the same manner as a single wire, 

 though in a less degree; and this I found was actually the case. 

 When four wires of fine platinum were made to complete a 

 powerful voltaic circuit, each wire exhibited its magnetism in 

 the same manner, and steel filings on the sides of the wires 

 opposite attracted each other. 



As the filings on the opposite sides of the wire attracted each 

 other in consequence of their being in opposite magnetic states, 

 it was evident, that if the similar sides could be brought in con- 

 tact, steel filings upon them would repel each other. This was 

 very easily tried with two voltaic batteries arranged parallel to 

 each other, so that the positive end of one was opposite to the 

 negative end of the other : steel filings upon two wires of plati- 

 num joining the extremities strongly repelled each other. When 

 the batteries were arranged in the same order, i. e. positive oppo- 

 site to positive, they attracted each other; and wires of platinum 

 (without filings) and fine steel wire (still more strongly) exhibited 

 similar phenomena of attraction and repulsion under the same 

 circumstances. 



As bodies magnetized by electricity put a needle in motion, 

 it was natural to infer that a magnet, would put bodies magnet- 

 ized by electricity in motion ; and this I found was the case- 

 Some pieces of wire of platinum, silver, and copper, were placed 

 separately upon two knife edges of platinum connected with two 

 ends of a powerful voltaic battery, and a magnet presented to 

 them ; they were all made to roll along the knife edges, being 

 attracted when the north pole of the magnet was presented, the 

 positive side of the battery being on the right hand, and repelled 

 when it was on the left hand, and vice versa, changing the pole 

 of the magnet. Some folds of gold leaf were placed across the 

 same apparatus, and the north pole of a powerful magnet held 

 opposite to them ; the folds approached the magnet, but did not 

 adhere to it. On the south pole being presented, they receded 

 from it. 



I will not indulge myself by entering far into the theoretical 

 part of this subject; but a number of curious speculations can- 

 not fail to present themselves to every philosophical mind, in 

 consequence of the facts developed ; such as whether the mag- 

 netism of the earth may not be owing to itfc electricity, and the 

 variation of the needle to the alterations in the electrical currents 

 of the earth in consequence of its motions, internal chemical 

 changes, or its relations to solar heat ; and whether the lumi- 

 nous effects of the auroras at the poles are not shown, by these 

 new facts, to depend on electricity. This is evident, that if 

 strong electrical currents be supposed to follow the apparent 



