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If a magnetic wire be twifted, its powers are fo difordered 

 that one fide of the wire, in fome places of it, will be attracted 

 and the other fide repelled by the fame pole of the magnet. 



The power of magnets (casterls parib.) is in proportion to 

 their furfaces or as the fquares of their diameters. — See Hutton's 

 Magnetifm, p. 72. 



Commiinicat'ion . 



When iron is applied to or brought within the fphere of 

 a€livity of a particular magnet, it acquires the arrangement re- 

 quifite to form the heteronymous pole, and thus becomes itfelf 

 in fome degree magnetic in its whole length, if this length be 

 not totally difproportioned to the power of the particular 

 magnet. 



Hence the other end of fuch bar of iron acquires the ar- 

 rangement of the oppofite pole, according to the laws of cry- 

 ftalization already laid down. 



Iron becomes magnetic either by contadl or proximity to a 

 magnet, or by pofition, or by internal commotion. 



If a bar of iron be placed in a vertical pofition its infenfibic 

 fibrillae gradually acquire the magnetic arrangement, fo that 

 after fome years it becomes a complete magntt, its l(mej? part 

 becoming a north pole, that is, pointing when free to the north, 



and 



