386 



Royal Academy of Sept. 30 1922; a few days, however, before the 

 meeting death took him away. Among the papers found after his 

 death was the manuscript of the above communication, ready 

 for tiie press, and a few detached slieets, on whicii the author tried 

 to ascertain what follows fi-om the equations : 



r,„ = c, -\- T 



U^I 



(li: 



{A) 





f-1 



\bojT 



= T 





(B) 



(C) 



dT\ T 



H 



dó' 



11 









m 



H\ 



'dhf 



which can be deiixed in a purely thermodynamic way, if they 



are combined with the empirical data on the course of ö ^ y (J*, //) 



in the neighbourhood of the Curie-point, or with the equation: 



no* 

 e = - — -^-f{T) (E) 



which is the direct consequence of the formula for the molecular 

 field Iljn used by Prof. Weiss: 



H,,= — f^ = na (F) 



It seems to have been his intention to throw light on the question 

 what suppositions are necessary to derive the change of the specific 

 heat of ferro- magnetic bodies at the Curie-point. 



P. E. 



