566 PLUCKER ON THE ACTION OF THE MAGNET 



29. The experiment described above proves that the different 

 flanaes which were examined act diamagnetically, and more- 

 over that they are all diamagnetic to a greater extent than the 

 £1 rrounding air. Granting, on the one hand, that finely-divided 

 carbon at a red heat exists in the flame of tallow, stearine and 

 wax candles, as also in that of turpentine, and on the other 

 hand solid phosphoric acid at a red heat in that of the phos- 

 phorus, and that the repulsion observed might be attributed to 

 these two bodies, by supposing that they carried off the red- 

 hot gases with them, — still in the other flames which were 

 examined no finely-divided solid bodies exist which could pro- 

 duce the repulsion. Thus the watery vapour of the hydrogen 

 flame, the carbonic acid mixed with watery vapour in the alcohol 

 flame, and the sulphurous acid in that of bunwig sulphur, are all 

 more powerfully diamagnetic when at a red heat than air. 



This i-emarkable result sui'prises us more when we consider 

 how rarified these gases are at a red heat, and we are involuntarily 

 led to inquire whether the elevated temperature is not favourable 

 to the appearance of diamagnetism, just as on the other hand it 

 diminishes magnetism. 



30. At the very commencement of my magnetic researches, 1 

 endeavoured, by means of the magnet, to detect the iron in an 

 alcoholic flame, the wick of which had been rubbed with finely- 

 divided protosulphate of iron, and which consequently burned 

 with a beautiful yellow light. I then obtained a negative result, 

 which in subsequent repetitions I found confirmed by the flame 

 not experiencing any less repulsion from the iron in admixture 

 than without it ; in fact even isolated particles of iron at a red 

 heat, which ascended with the flame, were not interrupted in 

 their motion by the magnet. 



31. The phaenomena which occurred with flame did not for an 

 instant leave room for the idea that the repulsion observed could 

 arise from currents of air. Such currents could only be pro- 

 duced by the action of the magnet upon it, not by the flame it- 

 self, because its action ceases simultaneously with the magnetism. 

 It might be imagined, as we regard the air as diamagnetic, that 

 when we apply the parallelopipedal halves of the keeper (A) as 

 in paragraph 28, the space between the surfaces of the poles of 

 the halves of the keeper acted as a chimney, in such a manner 

 that the air at those spots where the diamagnetic action was 

 strongest (the magnetism being strongest at the surfaces of the 



