THE INTELLECTUAL RISE IN ELECTRICITY. 



difference between such a physical interpretation as this, 

 and the assumption that the iron by sympathy or simili- 

 tude had become converted into a lodestone. 



That two lodestones fitted with armatures, so as to have 

 a common pole-piece, exert a much greater lifting force 

 than either separately. This is the compound magnet. 



That bodies, to use the modern term, can be saturated 



MAGNETIZING HOT IRON BY HAMMERING IT WHII.E HELD IN 

 THE MAGNETIC MERIDIAN. 1 



with magnetism. " Magnetic bodies,'* he says, "can 

 restore soundness (when not totally lost) to magnetic bod- 

 ies, and can give to some greater powers than they origi- 

 nally possessed ; but to those which, by their nature, are 

 in the highest degree perfect, additional strength cannot 

 be given." 



I have already made some reference to the orbs of virtue 



l From the first edition of Gilbert's treatise De Magnete. The work- 

 man is directed to place himself facing the north, and to hammer the hot 

 iron so that it will expand or elongate in a northerly direction. 





