 Born: 20 January 1775,
Lyon, France
Died: 10 June 1836,
Marseilles, France
A short segment follows which is an excerpt from an article by:
J J O'Connor and E F Robertson
It is worth commenting on how quickly Ampère produced this theory,
the inspiration striking him immediately he heard of Orsted's experimental
results. Orsted's work was reported the Academy in Paris on 4 September
1820 by Arago and a week later Arago repeated Orsted's experiment at an
Academy meeting. Ampère demonstrated various magnetic / electrical
effects to the Academy over the next weeks and he had discovered electrodynamical
forces between linear wires before the end of September. He spoke on his
law of addition of electrodynamical forces at the Academy on 6 November
1820 and on the symmetry principle in the following month. Ampère
wrote up the work he had described to the Academy with remarkable speed
and it was published in the Annales de Chimie et de Physique.
Ampère was assisted over the next few years in his work by Felix
Savary whose help in getting Ampère to write up his results was
invaluable [4]:-
... beginning with the memoir he completed
early in 1823, Savary now made much more creative contributions. But more
than his creativity, it was Savary's discipline and ability to concentrate
at length on specific problems that proved especially valuable to Ampère.
There is room to speculate that, without Savary's aid. Ampère might
never have found time to complete the detailed calculations required to
apply his force law to magnetic phenomena.
However Ampère was not the only one to react quickly to Arago's
report of Orsted's experiment. Biot, with his assistant Savart, also quickly
conducted experiments and reported to the Academy in October 1820. This
led to the Biot-Savart Law. Another who worked on magnetism at this time
was Poisson who insisted on treating magnetism without any reference to
electricity. Poisson had already written two important memoirs on electricity
and he published two on magnetism in 1826.
Ampère's most important publication on electricity and magnetism
was also published in 1826. It is called Memoir on the Mathematical Theory
of Electrodynamic Phenomena, Uniquely Deduced from Experience and contained
a mathematical derivation of the electrodynamic force law and describes
four
experiments. Maxwell, writing about this Memoir in 1879, says:-
We can scarcely believe that Ampère
really discovered the law of action by means of the experiments which he
describes. We are led to suspect, what, indeed, he tells us himself, that
he discovered the law by some process which he has not shown us, and that
when he had afterwards built up a perfect demonstration he removed all
traces of the scaffolding by which he had raised it.
Ampère's theory became fundamental for 19th century developments
in electricity and magnetism. Faraday discovered electromagnetic induction
in 1831 and, after
initially believing that he had himself discovered the effect in 1822,
Ampère agreed that full credit for the discovery should go to Faraday.
Weber also developed Ampère's ideas as did Thomson and Maxwell.
In 1826 Ampère began to teach at the Collège de France.
Here he was in a position to teach courses of his own design, rather than
at the Ecole Polytechnique were the topics were set down. Ampère
therefore taught electrodynamics at the Collège de France and this
course was taken by Liouville in 1826-27. This was the second time Ampère
had taught Liouville since Liouville had taken Ampère's courses
at the Ecole Polytechnique in the previous session. Liouville made an important
contribution to Ampère's electrodynamics course by editing a set
of notes taken from Ampère's lectures.
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