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FARADAY, MICHAEL
FARADAY, MICHAEL (1791–1867)
Michael Faraday was closely associated with some
of the most important pioneers of photography. He
worked hard to improve Britain’s glass production, es-
pecially important for large lenses. He also discovered
phenomena related to the optical behavior of materials
that became of use in the 20th century. He is, however,
more remembered as the single person most respon-
sible for the modern technology for the generation and
management of electric power. He also made many
contributions to chemistry. But his greatest importance
for photography was arguably his work on the relation
between electricity and magnetism. While this was fun-
damental to the generation of electric power it was also
the basis on which James Clerk Maxwell (1831–1879)
built his theory of electromagnetic waves, which ex-
plains much of the behavior of light and its relatives,
radio waves, infrared, microwaves, ultraviolet, x-rays
and gamma-rays.
Faraday was born to a father who was in trade as a
blacksmith, and had a short term of formal education,
which included essentially no mathematics. He appren-
ticed to a bookbinder at age 13 and became increasingly
interested in chemistry and electricity. Eventually he
was able to construct experimental equipment, based
on what he had read, using extremely simple materials.
By 1812 he had constructed, for example, a machine
to generate static electricity and accumulate an electric
charge, as well as a voltaic pile, what we would now
call a battery.
In the winter of 1810–11 Faraday attended a series
of public lectures on chemistry. He took careful notes,
which he illustrated. He presented these to his employer,
and not long after a patron of the store noticed them
and took Faraday to a public lecture at the Royal Insti-
tution by its laboratory director, Sir Humphrey Davy
(1778–1829), one of the most well known physicists
of the time. Faraday was enthralled, and when his ap-
prenticeship was up some months later he handed his
notes of the talks to Davy and requested employment as
Davy’s assistant. Some months later Faraday was hired
and began his career at the Royal Institution, his main
affi liation until his death.
A year after Faraday was hired he accompanied
Davy on a tour of major science laboratories on the
Continent. Faraday met scientists in Germany, France
and Italy, including Ampere, Humboldt, Gay-Lussac,
and Volta, the inventor of the voltaic pile. The people
he met he remained in contact with upon his return to
the Royal Institution.
The Royal Institution was a learned society es-
tablished in 1799 to promote organized research and
disseminate new knowledge. The former goal was
supported by the creation of a laboratory and a set of
research professorships, and a major research library.
The diffusion of knowledge was to be carried out both
by courses offered by the research professors. Faraday
founded a series of six talks at Christmas time for juve-
niles and carried them out himself for 19 years.
Faraday’s work for the fi rst several years was largely
in chemistry. He performed analyses for Davy and pub-
lished a number of short papers on them.
In 1820 Oersted, a Danish physicist discovered that
an electric current fl owing in a wire would orient a
compass needle at right angles to the wire. Repeating
Oersted’s experiment re excited Faraday’s interest in
electricity and magnetism, one which he eventually
became heavily involved with.
In 1821 Faraday married Sarah Barnard. He applied
for and received an addition to his rooms in the Royal
Institution. The couple occupied these rooms for the
rest of his career.
The same year he showed that a magnetic needle
could be made to rotate around a wire carrying an elec-
tric current. This is the principle of the electric motor,
though it took some years for practical designs to follow,
mostly because no source of large amounts of electric
power existed. Such sources awaited Faraday’s discov-
ery of the electric generator idea a decade later.
In the years immediately following he performed
mostly chemical experiments, including the 1825 dis-
covery of Benzol, which later became the basis of a
number of the aniline dyes, which still later came into
use as photographic sensitizing dyes.
Faraday became involved with glass production in the
following way. In the early 1800s the British had domi-
nated the supply of high quality optical glass and the
instruments, such as camera obscuras, telescopes and
microscopes, made from it. But in the 1810s and twen-
ties a new supplier, a young German named Fraunhofer,
began to produce much better glass of considerably
larger diameters, and through using the glass in large
prisms discovered that the spectrum of the Sun was a
rainbow crossed by dark lines at fi xed colors (founding
modern spectroscopy). These lines in turn he was able
to use as high precision sign posts to measure the qual-
ity of his glass, and to give it precise specifi cations for
his customers. Fraunhofer became the world leader in
supplying large lenses and prisms.
This naturally concerned the British and the Joint
Committee of the Board of Longitude and the Royal
Society for the Improvement of Glass for Optical
Purposes was established in 1824. It at fi rst included a
number of well-known physicists, such as Humphrey
Davy, Thomas Young, and Sir John Herschel as well
as lens maker George Dolland and glassmakers Pellat
and Green were added. Faraday was engaged to do a
chemical analysis of samples of Fraunhofer’s glass.
This he did and handed the derived compositions to
the glassmakers, working on the assumption that this