who quote against it the absence of all attraction when the magnet and
metal are at rest (62. 126.), although the induced magnetism should still
remain; and who, from experiments made with a long dipping needle, conceive
the action to be always repulsive (125.).

[A] Philosophical Transactions, 1825, p. 467.

83. Upon obtaining electricity from magnets by the means already described
(36 46.), I hoped to make the experiment of M. Arago a new source of
electricity; and did not despair, by reference to terrestrial
magneto-electric induction, of being able to construct a new electrical
machine. Thus stimulated, numerous experiments were made with the magnet of
the Royal Society at Mr. Christie's house, in all of which I had the
advantage of his assistance. As many of these were in the course of the
superseded by more perfect arrangements, I shall consider myself at liberty
investigation to rearrange them in a manner calculated to convey most
readily what appears to me to be a correct view of the nature of the
phenomena.

84. The magnet has been already described (44.). To concentrate the poles,
and bring them nearer to each other, two iron or steel bars, each about six
or seven inches long, one inch wide, and half an inch thick, were put
across the poles as in fig. 7, and being supported by twine from slipping,
could be placed as near to or far from each other as was required.
Occasionally two bars of soft iron were employed, so bent that when
applied, one to each pole, the two smaller resulting poles were vertically
over each other, either being uppermost at pleasure.

85. A disc of copper, twelve inches in diameter, and about one fifth of an
inch in thickness, fixed upon a brass axis, was mounted in frames so as to