370 IDENTITY OF MAGNETISM AND ELECTRICITY, [s. xxxm. 



leaves and fruit, even a man or an animal, if suspended, 

 would take the equatorial or rectangular direction, since all 

 the substances of which they are formed possess that pro- 

 perty. All the gases are diamagnetic, whether light or 

 heavy ; but oxygen is less so than any other, and that is the 

 reason why atmospheric air is more feebly diamagnetic 

 than any other substance : when hot, however, it is much 

 more diamagnetic ; when very cold, it is magnetic. Signer 

 Bancalore, of Venice, has discovered that flame has the dia- 

 magnetic property. The flame of a taper placed between 

 the poles of an electro-magnet is immediately divided into 

 two tongues by the electric current, which diverge equa- 

 torially, that is, at right angles to the electric current. 



A bar of copper presented a singular phenomenon when 

 exposed by Dr. Faraday to an electro-magnetic current. 

 When there was no current, the copper bar was made to re- 

 volve by the torsion of the thread by which it was suspended ; 

 but, the instant the current of electricity began to flow, the 

 copper bar came to a dead halt, and when the current 

 ceased there was a strong revulsion, and the bar revolved 

 the contrary way. There was no revulsion, however, when 

 the bar was arrested in the axial or equatorial line of force. 

 Bismuth and other diamagnetics assume the equatorial 

 position after several revolutions, but the copper is in- 

 stantly arrested wherever it may point. Various metals 

 have that property in a greater or less degree. 



