vol. iii. p. 3, footnote.)


Chapter 3.

Discovery of Magneto-electricity: Explanation of Argo's magnetism of
rotation: Terrestrial magneto-electric induction: The extra current.

The work thus referred to, though sufficient of itself to secure no
mean scientific reputation, forms but the vestibule of Faraday's
achievements. He had been engaged within these walls for eighteen
years. During part of the time he had drunk in knowledge from Davy,
and during the remainder he continually exercised his capacity for
independent inquiry. In 1831 we have him at the climax of his
intellectual strength, forty years of age, stored with knowledge and
full of original power. Through reading, lecturing, and experimenting,
he had become thoroughly familiar with electrical science: he saw
where light was needed and expansion possible. The phenomena of
ordinary electric induction belonged, as it were, to the alphabet of
his knowledge: he knew that under ordinary circumstances the
presence of an electrified body was sufficient to excite, by
induction, an unelectrified body. He knew that the wire which
carried an electric current was an electrified body, and still that
all attempts had failed to make it excite in other wires a state
similar to its own.

What was the reason of this failure? Faraday never could work from
the experiments of others, however clearly described. He knew well
that from every experiment issues a kind of radiation, luminous in
different degrees to different minds, and he hardly trusted himself