PLUCKER ON THE THEORY OF DIAMAGNETI8M. 33? 



tion and was therefore repelled, retained its north magnetism 

 for a time after the north pole of the electro-magnet, by reversing 

 the current, was converted into a south pole ; the consequence 

 of this was the observed attraction of the bismuth. The strong 

 south pole of the magnet however soon changed the magnetism 

 of the end in question of the bismuth bar into south magnetism, 

 and the immediate consequence of this was repulsion. 



18. If we combine both the former and the latter of these ex- 

 periments, we cannot fail to arrive at the conviction, that diamag- 

 netism is identically the same as ordinary magnetism. If we 

 assume iron to be the representant of magnetic bodies, we must 

 of course forget the enormous difference in point of strength. 

 That this difference however may disappear, we should prefer 

 taking some less magnetic metal, say platinum, in its place. 



A little bar of bismuth, between the poles of a magnet, 

 becomes then a real magnet, and differs from a bar of platinum 

 only in the circumstance, that its poles are the reverse of those 

 of the latter metal. We need only imagine the bismuth to 

 be reversed longitudinally, nay, we may actually reverse it, and 

 in the moment after reversion we obtain two magnets which are 

 not to be distinguished from each other. If both retained the 

 condition which they assume between the magnetic poles and 

 could be removed in this condition from the magnetic field, then 

 if we did not know the actual positions which they assumed 

 between the poles, we could by no means decide which of them, 

 whether platinum or bismuth, was the magnetic body. The 

 word diamagnetic would be therefore superfluous, while regarding 

 the magnetic condition of different bodies. 



19. Bismuth and iron both assume their magnetic state under 

 the same circumstances, by induction, which can proceed from a 

 magnet just as well as from the wires of a helix. This induction, 

 however, if we regard the polarity excited by it, exhibits itself 

 antithetically in bismuth and iron. We must distinguish a mag- 

 netic from a diamagnetic induction', according as the induced body 

 is magnetic or diamagnetic, the first or the second takes place. 

 In the case of diamagnetic induction, a north pole excites a 

 north pole, and a south pole a south pole, in the nearer particles 

 of the induced body ; while in the case of magnetic induction, 



