38 DR. FARADAY’S EXPERIMENTAL RESEARCHES IN ELECTRICITY. (SERIES XXVI.) 
rate to fulfil the requisite condition of equilibrium of forces. Finally, a paramagnetic 
and a diamagnetic body attract each other (2817-)5 they ought to do so, for the 
diamagnetic body finds a place of weaker action towards the paramagnetic body, and 
the paramagnetic substance finds a place of stronger action in the vicinity of the dia- 
magnetic body, D P, fig. 6. 
2832. I have frequently spoken of iron in illustration of the action of paramagnetic 
conductors, and considered the polarity which it acquires as the same with that of 
these conductors ; but I must now make clear a distinction, which exists in my mind, 
with regard to the polarity of a magnet, and the polarity, as I have called it, due to 
mere conduction. This distinction has an important influence in the case of iron. A 
permanent magnet has a polarity in itself, which is possessed also by its particles ; and 
this polarity is essentially dependent upon the power which the magnet inherently pos- 
sesses. It, as well as the power which produces it, is of such a nature, that we cannot 
conceive a mere space void of matter to possess either the one or the other, whatever 
form that space may be supposed to have, or however strong the lines of magnetic force 
passing across it. The polarity of a conductor is not necessarily of this kind, is not due 
to a determinate arrangement of the cause or source of the magnetic action, which in 
its turn overrules and determines the special direction of the lines of force (2807.), but 
is simply a consequence of the condensation or expansion of these lines of force, as the 
substance under consideration is more or less fitted to convey their influence onwards. 
It is evidently a very different thing to originate such lines of power and determine 
their direction on the one hand, and only to assist or retard their progression without 
any reference to their direction on the other. Speaking figuratively, the difference 
maybe compared to that of a voltaic battery and the conducting wires, or substances, 
which connect its extremities. The stream of force passes through both, but it is the 
battery which originates it, and also determines its direction ; the wire is only abetter 
or worse conductor, however by variation of form or quality it may diffuse, condense, 
or vary the stream of power. 
2833. If this distinction be admitted, we have to consider whether iron, when 
under the influence of lines of magnetic power, becomes a magnet and has its proper 
polarity, or is a mere paramagnetic conductor with conducting powers of the highest 
possible degree. In the first place, it would have the real polarity of the magnet, in 
the second only that which I assign to oxygen and other conducting bodies. To my 
mind the iron is a magnet. It can be raised as a source of lines of magnetic power to 
an extreme degree of energy in the electro-magnet ; and though, when very soft, it 
usually loses nearly all this power upon the cessation of the electric current, yet 
such is not the case if the mass of metal forms a continuous circuit or ring, for then 
it can retain the force for hours and weeks together, and is evidently for the time 
an original source of power independent of any voltaic current. Hence I think 
that the iron under the influence of lines of magnetic power becomes a magnet ; and 
though it then has the same kind of polarity, as to direction, as a mere paramagnetic 
