THE 

 LONDON, EDINBURGH and DUBLIN 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



[FOURTH SERIES.] 



FEBRUARY' 1855. 



XIII. On some Points of Magnetic Philosophy. 

 By Professor Faraday, D.C.L.,F.R.S. $c* 



8300. TT7ITHIN the last three years I have been bold 

 ▼ » enough, though only as an experimentalist, to 

 put forth new views of magnetic action in papers having for 

 titles, "On Lines of Magnetic Force f," and "On Physical 

 Lines of Magnetic Force J." The first paper was simply an 

 attempt to give, for the use of experimentalists and others, a 

 correct expression of the dual nature, amount, and direction of 

 the magnetic power both within and outside of magnets, apart 

 from any assumption regarding the character of the source of the 

 power ; that the mind, in reasoning forward towards new develop- 

 ments and discoveries, might be free from the bondage and de- 

 leterious influence of assumptions of such a nature (3075. 3243.). 

 The second paper was a speculation respecting the possible phy- 

 sical nature of the force, as existing outside of the magnet as well 

 as within it, and within what are called magnetic bodies, and 

 was expressly described as being entirely hypothetical in its 

 character (3243.). 



3301. There are at present two, or rather three general hypo- 

 theses of the physical nature of magnetic action. First, that of 

 aethers, carrying with it the idea of fluxes or currents, and this 

 Euler has set forth in a simple manner to the unmathematical 

 philosopher in his Letters § ; — in that hypothesis the magnetic 



* Communicated by the Author, 

 t Phil. Trans. 1852, p. 25. 

 X Phil. Mag. 1852, June, p. 401. 



§ Euler's Letters, translated, 1802, vol. i. p. 214 ; vol. ii. pp. 240. 242. 

 244. 



Phil. May. S. 4. Vol. 9. No. 57. Feb. 1855. G 



