Michael Faraday
A summary of the life and times of Michael Faraday, often called the Father
of Electrical Engineering.
Called the Father of Electrical Engineering and the greatest
scientist of his day, Michael Faraday came from a humble background and received
little formal education. In his lifetime he achieved a great amount in many
spheres of scientific discovery whilst also being a brilliant and charismatic
lecturer. Michael Faraday is best known for formulating the laws of
electromagnetic induction, and laying the foundations necessary to make electric
motors, dynamos and transformers. On top of this he devised the laws of
electrolysis, was the first to liquefy chlorine, to isolate benzene and he also
discovered magneto-optical effects. Through all of this he was a deeply
religious and humble man whose scientific knowledge and religious beliefs were
in harmony.
Faraday's Birth
Michael Faraday was born on 22nd September 1791 in Newington Butts,
an area now covered by the Elephant and Castle, just south of the River Thames
in London. His father, James Faraday was a blacksmith who had moved to London
from Westmorland a few years earlier. He was also a member of the Sandemanian
sect of the Christian Church, and this had a profound effect on Michael
Faraday's adult life. Not only were the Sandemanians strict Christians, but they
also encouraged their members to read - it was important to be able to read the
Bible. Accordingly Faraday became an avid reader, a factor that enabled him to
educate himself later.
At school the young Michael Faraday only learned the
rudiments of reading writing and arithmetic, and then at the age of fourteen in
1805, he was apprenticed to George Reibau as a bookbinder. Here he was able to
read many books and improve his standard of education. He read many scientific
books, and he also repeated many of the experiments on his own, even building
his own electrostatic machine. He also joined the City Philosophical Society in
1810, the place where he was to give his first lectures. Aware of his need to
improve himself, he persuaded a friend to tutor him in grammar for two hours a
week, an arrangement that continued for seven years!
In 1812, Faraday managed to obtain some tickets to listen to
lectures by Sir Humphrey Davy of the Royal Institution. He attended them and
took notes during the lectures. Later that year he applied to Davy for a
position but Davy had no vacancies. However early in 1813 Davy's Chemical
Assistant was involved in a fight in the main lecture theatre of the Royal
Institution and was dismissed. Davy remembered Faraday and invited him in for an
interview, after which he offered him the position.
Initially Michael Faraday worked under Davy, and later under
Davy's replacement, William Brande. However between 1813 and 1815 he accompanied
Davy as his assistant on a scientific tour of the continent. As Britain and
France were at war, permission had to be obtained from Napoleon himself. This
granted they set off on their travels around Europe, visiting Paris, Italy
(where they met the aged Volta), Switzerland, Athens and Constantinople. On
their return to England in April 1815 Faraday resumed his position at the Royal
Institution.
Turning to electricity
In 1820 the Danish philosopher Hans Christian Oersted discovered
electro-magnetism. He had shown that when an electric current was passed trough
a wire close to a pivoted magnetic needle, it was deflected, indicating that the
current flowing caused a magnetic field to be set up.
Faraday took an interest in Oersteds discovery because at
this time, electricity was considered to be allied to chemistry. He made some
further investigations. In one experiment undertook in 1821 he passed a current
through a wire that was in the magnetic field from a strong horseshoe magnet and
discovered that the wire moved. Although obvious today, this was a major
milestone in the understanding of electricity and magnetism and brought him
considerable renown. This meant the way was now open to create mechanical motion
from magnetism and an electric current.
After this Michael Faraday returned to his chemical
researches and it would not be for another ten years that he would make any
further contributions to electrical science. In 1823 he succeeded in liquefying
chlorine, and then in 1825 he discovered a chemical he called bicarbuet of
hydrogen, but known today as benzene. He also spent many years making and
investigating optical glass.
From the days when he had attended the City Philosophical
Society, Faraday had always enjoyed lectures. He was also a very gifted lecturer
himself, and he believed in sharing his knowledge and wonder of the science of
his surroundings. Accordingly in 1826 he founded the Friday Evening Discourse,
and later that year he commenced the Christmas Lectures. Both of these continue
to this day, the Christmas lectures being televised. Faraday actively
participated in both, giving a total of 123 Friday Discourses and 19 Christmas
lectures. Whenever he lectured the auditorium was full, indicating his immense
popularity and like many of his other achievements it was the result of much
practice and effort. However it was recorded in one lecture that an elderly
gentleman in the front row fell asleep and snored loudly. Faraday paused and
some clapping gradually broke out. The elderly gentleman awoke and joined in the
applause to everyone's amusement. Faraday then resumed his discourse.
Electro-magnetic work resumes
Although Faraday's work had focussed upon other researches, the idea of
electromagnetism had never been far from his mind. Indeed his notes from 1821
contain the words "Convert magnetism into electricity", and he had periodically
performed a few experiments during the following years, but without any success.
Then in 1831 he completely focussed his efforts on electromagnetism. In just ten
days he succeeded in discovering the principles of electromagnetic induction,
although he refined the work for some years afterwards. Until this time, people
had thought that a magnetic force could be changed into electricity. It was
Michael Faraday who demonstrated that the magnetic flux around a wire had to
change before any induced current flowed.
His most famous experiment consisted of a ferrite ring on
which there were two separate windings of insulated wire. A battery was
connected to one, and a galvanometer to the other. Only when the battery was
connected or disconnected did the galvanometer deflect. In a second experiment
Faraday placed a rotating copper disk between the poles of a large permanent
magnet. He showed that a current could be obtained in a conductor that extended
from the axis of the disk to its edge.
In some experiments with static electricity he developed a
similar idea of electric lines of force and he undertook many experiment's
concerning dielectrics and non-conducting materials. Out of this work he
developed the idea of what he called the specific inductive capacity, or what we
know today as the dielectric constant.
It was also during this period, 1832 - 1834, to be exact,
that Faraday undertook his work on electrochemical action. He coined the words
loved by schoolboys of electrode, cathode, anode and ion to name but five.
The work on electromagnetism and electrostatics was at the
forefront of his work for most of the time, and he put himself under
considerable pressure to complete it. Unfortunately this took its toll on his
health and coupled with the fact that he also became an elder in his church,
there was a sharp decline in the level of his research work and his lecturing in
the early 1840s.
Work restarts
Around 1844 Michael Faraday commenced another period of work. This was to be his
last, and the main discovery was that he was able to rotate the plane of
polarisation of light passing through some heavy glass that was in the magnetic
field from a powerful electromagnet. When the electromagnet was turned on and
off the state of the polarisation of the light changed.
With these and other observations, Faraday delivered a major
lecture in April 1846 entitled "Thoughts on Ray-vibrations". This set the basis
for Faraday's theory of electromagnetism he developed in the following years.
This work was later taken up by James Clerk Maxwell who developed his famous
equations that describe electromagnetic waves which in turn lead to the physical
discovery of radio waves.
Retirement
In view of his tremendous contribution to science he was offered a grace and
favour cottage at Hampton Court in 1858. With advancing age, ill health took its
toll. His powers of reasoning were not as good as they had been and he suffered
from loss of memory. Realising that he could not keep up his original pace of
work he began to retire from his many commitments from about 1860. Although
still interested in science, he contented himself with a quieter life. However
six years later in 1864 he was offered the presidency of the Royal institution.
A humble man he was shocked that he would even be considered for the post and
declined. He died three years later on 25th August 1867 and was buried in the
Sandemanian plot in Highgate Cemetery.
He is famous for the immense number of discoveries he made
and their importance yet he was also humble, taking his Christian faith very
seriously. In doing this he donated a portion of his income to the church and
also spent time visiting the sick. He was also a warm character, but on some
occasions he could be fiery. He generally kept his temper under control,
channelling it into his work where it manifest itself in a truly remarkable
level of output. He also had a good sense of humour. Once when he was explaining
a discovery to Gladstone who was Chancellor at the time he was asked, "But after
all what use is it?" Faraday quickly responded saying, "Why sir, there is every
probability you will be able to tax it."
Today Michael Faraday is fittingly remembered as a truly
remarkable scientist. Working tirelessly on little more than a wooden bench with
crude instruments he opened up many of the fundamental laws of electrical
science. He also had the rare gift of true genius combined with the ability to
describe his ideas clearly and to enthuse others. Fittingly the unit of
capacitance is named after him as a tribute.
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