328 B. Rosing on the Participation of Matter 



changes of volume or form, but of the structure of matter — 

 like that which takes place in recalescence, as is most pro- 

 bable, — then there is nothing impossible in this hypothesis. 

 The explanation of another very important phenomenon — 

 magnetic hysteresis — is based on the same phenomenon of 

 magnetic deformations ; we must only suppose that the 

 same hysteresis exists in the changing of magnetic defor- 

 mations. 



It is also interesting to see to what our hypothesis could 

 lead in the case of a diamagnetic substance. In this last case, 

 when k<0, i. e. the reflexion of magnetic induction from the 

 particles of matter takes place with the changing of the sio-n ? 

 the absorption of energy by deformations gives rise to a quite 

 opposite effect. Formula (29) shows that when /e<0, the 



7T . 



absolute value of -ttj cannot be more than k, 



f/n 



-1 



K = 



4 tG+'K" 



because, as it is very easy to see from this formula, the fol- 

 lowing inequality always holds here, 



3 Ve 



> 



Further, the same formula shows that — & is lessened always 



B F 



with increasing of ^-^ ; and therefore in all such cases, when 



magnetic deformations increase the most the differential 



coefficient -^ falls to its least value, 

 ai± 



Owing to this, when we assume the character of the change 

 of deformations in a diamagnetic body to be the same as in a 

 paramagnetic one, we shall have for a diamagnetic substance a 

 curve of magnetization of quite a different form, namely, like 

 the line OMN shown in the figure. Similarly, when the mag- 

 netizing force is decreased, the deformations change more 

 slowly, in consequence of hysteresis, than when it is in- 

 creased, and the return curve NPQ descends below the 

 curve OMN and intersects the axis of H before in the 

 point P. Again, with a further decrease of H, magnetization 

 becomes positive, and the body at H = has a paramagnetic 

 residual. This, as is known, was observed by Messrs. Quintus- 

 Icilius, Tumlirtz, Lodge, and others. 



Besides the differential equation of magnetization, it is 



