194 WEBER ON THE CONNEXION OF DIAMAGNETISM 



For the bar of iron (where all the inductive shocks were thus 

 concentrated), the corresponding limit-value is found to be 



= - 83-876. 



From a great number of similar experiments, executed by various 

 observers, we find the ratio of the limit- value for bismuth to that 

 for iron to be 



+ 16-956: - 83-49. 



Now the intensity of the currents induced by bismuth and by 

 iron is directly proportional to these limit-values, and inversely 

 proportional to the number of inductive shocks during a time of 

 oscillation (that is, as 



1 : 216-2, 



because in the experiments with the bismuth bar 216-2 shocks, 

 and with the iron bar only 1 shock, took place during a time of 

 oscillation). Hence the currents induced by the diamagnetic bar 

 of bismuth xoere opposed in direction to those induced by the mag- 

 netic bar of iron, and their intensities were in the ratio of 



16-956 : 83-49 . 216*2 = 1 : 1064-5, 



although the bismuth bar weighed 339300 milligrammes, and 

 the iron bar only 790*86. From this we find by calculation, 

 that a bar of bismuth of the same weight as a bar of iron would 

 induce a current 456700 times weaker than the latter. This 

 result is only true however for a definite form of the bar of iron, 

 and for a definite amount of magnetizing force, namely X = 3012, 

 which is determined from the measured strength of the current, 

 and the number of coils of the electro-magnetic spiral. 



On the dependence of the Strength of the Magnetism of Change- 

 able Magnets upon the amount of the Magnetizing or Electro- 

 magnetizing Force, 



From the theory of diamagnetism, in connexion with that of 

 magnetism, discussed in the foregoing pages, it follows, that the 

 assumption of two magnetic fluids capable of free motion in the 

 molecules of iron, hitherto made in the case of magnetism, (and 

 from which the proportionality of the magnetism to the magnet- 

 izing force follows as a consequence) is not admissible, and that 



