Lecture on a new property of Magnetism. 



533 



a tube, make them into a long cylinder, and it will stand along the 

 line of force as bismuth did, precisely contrary to what the magnet 

 does, forming a beautiful contrast to it ; and then the phenomena 

 show us that this magnetic force not only has that same kind of 

 duality as respects electricity, as respects northness and southness, 

 but it has another duality, it has that kind of power which makes it 

 magnetic as iron, but in a contrary direction. But we now pass 

 from iron and nickel, the first condition, then nought, and then 

 beyond that to another, the reverse of iron. There is a table behind 

 me to show how various substances are placed in relation to magnetic 

 and diamagnetic action. 



Magnetics. 



Iron. 





Palladium. 



Nickel. 





Crown glass. 



Cobalt. 





Platinum. 



Manganese. 



Neutral. 



Osmium. 



Air and vacuum. 







Diamagnetics. 





Arsenic. 





Flint glass. 



Ether. 





Tin. 



Alcohol. 





Heavy glass. 



Gold. 





Antimony. 



Water. 

 Mercury. 





Phosphorous. 

 Bismuth. 



From iron to osmium these substances are magnetic. Air and 

 vacuum come into a strange neutral condition ; and after them come 

 the other bodies as diamagnetics, from arsenic to bismuth, and 

 a thousand more that might be added. I have shewn phosphorous 

 and bismuth, because they are striking ; and I will shew water, 

 because, when you see that water is magnetic, you will have a better 

 insight into the phenomena of nature than if I left you without 

 that indication. It is not so diamagnetic, to distinguish it from 

 magnetism, as bismuth is, but it is very much affected. Here is a 

 little tube which contains pure water, the glass of which is so nearly 

 balanced in the diamagnetic and magnetic part, as not to be affected, 



