W. A. Norton on Molecular Physics. 67 
According to this view, permanent magnetization consists in . 
polarizing the molecules, and it is this induced state which de- 
of a certain intensity. A certain amount of force (‘coercive 
force’’), and a certain interval of time, are expended in develop- 
the compound molecules of the mass, in the opposite direction 
to the inducing current; and that these currents result from the 
second mode of operation of the external force of the prim 
current, (p. 65). Accordingly, the susceptibility to diamag- 
SPpracie< : A 
Electro-Magnetism.—The essential theory of the developement 
of magnetism by electric currents, and of electro-magnetic phe- 
nomena generally, is embraced in what has already been stated, 
(pp. 63-4-5). : 
Magneto-Electricity.—The excitation of electric oe 
magnetic action is a phenomenon of pure induction, and il 
be included under the next head. 
Induction of Electric Currents—The term induction, as ordin- 
tily used in Dynamical Electricity, has reference only to the 
development of currents, through wires, or upon the surfaces, or 
Within the mass of bodies. It will suffice to confine our atten- 
tion to the origination of currents in wires forming a closed 
circuit. The general idea of the process, as contemplated from 
our theoretical point of view, has already been indicated. The 
