Faraday, Michael, 1791-1867; Physicists -- Great Britain -- Biography
He looks at the crystal acted upon by the magnet. From its mass he
passes, in idea, to its atoms, and he asks himself whether the power
which can thus seize upon the crystalline molecules, after they have
been fixed in their proper positions by crystallizing force, may
not, when they are free, be able to determine their arrangement? He,
therefore, liberates the atoms by fusing the bismuth. He places the
fused substance between the poles of an electro-magnet, powerfully
excited; but he fails to detect any action. I think it cannot be doubted
that an action is exerted here, that a true cause comes into play; but
its magnitude is not such as sensibly to interfere with the force of
crystallization, which, in comparison with the diamagnetic force, is
enormous. 'Perhaps,' adds Faraday, 'if a longer time were allowed, and
a permanent magnet used, a better result might be obtained. I had built
many hopes upon the process.' This expression, and his writings
abound in such, illustrates what has been already said regarding his
experiments being suggested and guided by his theoretic conceptions. His
mind was full of hopes and hypotheses, but he always brought them to an
experimental test. The record of his planned and executed experiments
would, I doubt not, show a high ratio of hopes disappointed to hopes
fulfilled; but every case of fulfilment abolished all memory of defeat;
disappointment was swallowed up in victory.
After the description of the general character of this new force,
Faraday states with the emphasis here reproduced its mode of
action: 'The law of action appears to be that the line or axis of
MAGNE-CRYSTALLIC force (being the resultant of the action of all the
molecules) tends to place itself parallel, or as a tangent, to the
magnetic curve, or line of magnetic force, passing through the place
where the crystal is situated.' The magne-crystallic force, moreover,
appears to him 'to be clearly distinguished from the magnetic or
diamagnetic forces, in that it causes neither approach nor recession,
consisting not in attraction or repulsion, but in giving a certain
determinate position to the mass under its influence.' And then he goes
on 'very carefully to examine and prove the conclusion that there was no
connection of the force with attractive or repulsive influences.' With
the most refined ingenuity he shows that, under certain circumstances,
the magne-crystallic force can cause the centre of gravity of a highly
magnetic body to retreat from the poles, and the centre of gravity of a
highly diamagnetic body to approach them. His experiments root his mind
more and more firmly in the conclusion that 'neither attraction nor
repulsion causes the set, or governs the final position' of the crystal
in the magnetic field. That the force which does so is therefore
'distinct in its character and effects from the magnetic and diamagnetic
forms of force. On the other hand,' he continues, 'it has a most
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