62 



HENRY A. ROWLAND 



$ is the magnetizing-force acting on the metal. 



23 is the magnetic induction within the metal (see Maxwell's ' Trea- 

 tise on Electricity and Magnetism/ arts. 400, 592, and 604). 



i 

 fj. is the magnetic permeability of the metal s=_=4*-H. 



s? 

 T is the portion of 23 which disappears when the current is broken. 



P is the portion of 33 which remains when the current is broken. 



qa a 



$ is the intensity of magnetization = - 



ow 



ic is Neumann's coefficient of induced magnetization = ^. 



*Q 



TABLE I. 



CAST NICKEL, NOKMAL, AT 15 C. 

 Experiments made November 29, 1873. 



ooo 



= 222 sin 



/"= 



359 



=17 6 sin 



28 



TABLE II. 



CAST NICKEL, MAGNETIC, AT 12 C. 

 Experiments made December 6, 1873. 



