THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



[FOURTH SERIES.] 



FEBRUARY 1875. 



XI. Studies on Magnetism. By E. Bouty, Professor of 

 Physics at the Lycee ofRheims*. 



UP to the present time there does not exist a complete theory 

 of the magnet. Notwithstanding the relative simplicity 

 of the phenomena presented by soft iron, one could not expect to 

 explain these apart ; and the study of steel magnets is still too 

 little advanced to supply the elements of a satisfactory physical 

 theory. 



Such being the situation, I thought that an experimental and 

 close investigation of the phenomena presented by steel magnets 

 (e.g. those accompanying their production, union, or separation) 

 would not be devoid of interest. The present is a first attempt 

 in this direction. The questions which form the subject of it, 

 though hitherto very little studied, would yet offer numerous 

 numerical verifications for any accurate theory of magnetism ; 

 and this would suffice to render highly important researches of 

 the sort we have undertaken. 



Most of the investigations the subject of which has been magne- 

 tization by currents refer to soft iron. Lenz and Jacobif, Joule J, 

 M\iller§, Wiedemann || especially, and more recently Quintus 

 Icilius %, Stoletow **, and Rowland ft preoccupied themselves 

 with determining the magnetic moments, temporary or perma- 



* Translated from a copy, communicated by the Author, of a Thesis 

 presented to the Faculty of Sciences, Paris, 1874. 



t Pogg. Ann. vol. xlvii. (1839). % Phil. Mag. S. 3. vol. ii. (1839). 



§ Pogg. Ann. vols, lxxix. & lxxxii. (1850, 1851). 



|| Ibid. vols, c, cvi. & cxvii. (1857-1862). H Ibid. vol. cxxi. (1864). 



** Phil. Mag. January 1873. tt Ibid. August 1873. 



Phil. Mag. S. 4. Vol. 49. No. 323. Feb. 1875. G 



