James Clerk Mawell
- a man of equations
James Maxwell is arguably one of the most important scientists of the
nineteenth century. Many scientists rank him alongside names such as Albert
Einstein and Sir Isaac Newton. This is because his revolutionary work in
defining electromagnetic radiation in terms of his field equations formed the
foundations for many others to develop their work upon. It lead to the discovery
and understanding of radio waves and the development of radio and wireless
technology that is an integral part of today's world. Indeed such is the
importance of his work that Albert Einstein described it as the "most profound
and most fruitful that physics had experienced since the time of Newton."
Today RF engineers know of the name Maxwell as a result of his equations.
Some might be able to write down or manipulate his equations, but very few
people would know much of the man himself.
Early life
James Clerk Maxwell was an only child born into a comfortable middle background
at 14 India Street in Edinburgh on 13th June 1831. His parents John
and Frances were married in 1826 and after the birth of their son they moved to
"Glenair" a newly built home on the family estate in rural Kirkcudbrightshire
which had been inherited by the family.
Even from an early age Maxwell showed a very keen interest in all around him.
He question those around him and he constantly asked, "What's the go o' that?
What does it do?" Apparently he was not content with a vague answer and would
press his question home until a satisfactory answer was given.
Sadly James' mother died in 1839 from abdominal cancer. She had obviously
been in great pain because when Maxwell was told that "she was in heaven now" he
was reported to have remarked, "I'm so glad she'll have no more pain."
His parents' plan was that they should educate the young James at home until
he was 13 and then he would attend Edinburgh University. However his mother's
death meant that other plans were needed. Initially a 16 year old boy was hired
to teach him. This arrangement did not work and his aunt, Jane Cay helped out by
looking after him so that in 1841 he was able to attend the Edinburgh Academy.
However he paid frequent visits to his father to whom he became very close.
Whilst at the Academy he was initially thought to be shy and dull and he was
slightly eccentric. He made no friends and he spent much of his free time
reading, drawing unusual diagrams and making mechanical models. As a result he
gained the nickname "Dafty" which he made no attempt to loose. However he
surprised many people when at the age of fourteen, he published his first
scientific paper in the proceedings of the Royal Society of Edinburgh. The paper
concerned ellipses and although Descartes had previously covered the subject of
the work, it was still a remarkable achievement for a fourteen year old.
University Life
Then at the age of sixteen, his father enrolled him at Edinburgh University. He
spent three years here, alternating his time between Glenair and Edinburgh. At
the University, he studied a variety of topics from polarised light and the
stereoscope to galvanism, rolling curves and the compression of solids. He had a
further paper presented, although this was read for him in view of his age.
Maxwell had to make a decision about his career. He had been expected to
follow his father into law, but as Maxwell said, he felt he was called upon to
study "another kind of law". Thus, three years after entering Edinburgh
University, Maxwell moved to Cambridge. He found this difficult because it meant
leaving his father. There were also concerns about his delicate health.
Nevertheless he moved to Cambridge in 1850. His tutor commented that he had a
mass of knowledge that was really immense for such a young man, but it was in a
state of considerable disorder. He spent his time at Cambridge at Trinity
College where he believed it would be easier to obtain his fellowship! Here he
studied mathematics and after his three years of what he termed very pleasant
and very strengthening work he sat for his Tripos in January 1854 and came
second.
First discoveries
Maxwell stayed on at Cambridge and spent time working on an extension of
Faraday's theories of electricity and lines of magnetic force. A paper resulting
from this work entitled "On Faraday's lines of force" was read to the Cambridge
Philosophical Society in two parts in 1855 and 1856. It showed that a few
relatively simple mathematical equations could describe the electric and
magnetic fields and the interaction between them.
Whilst Maxwell was making these major achievements and was enjoying his time
his father became ill in 1856. Maxwell wanted to be with him and so he moved to
Scotland to take up the position of Professor of Natural Philosphy at Marischal
College In Aberdeen. However just after accepting the position Maxwell's father
died. Nevertheless Maxwell still took up the post and started in November 1856.
A little later St John's College in Cambridge announced that the subject for
the Adam's prize was to be the motion of Saturn's Rings. Maxwell and a friend
had talked about them when they were at Edinburgh Academy and he became very
interested the prize. Accordingly much of his first two years research in
Aberdeen were devoted to this topic. In his analysis he showed that the rings
could only exist if they were made up from small solid particles, a fact that
was confirmed well over a hundred years later when the spacecraft Voyager
investigated them. Not surprisingly Maxwell's research earned him the Adam's
prize.
During his time at Aberdeen, Maxwell met Katherine Dewar, and the two were
married in 1859. Although the couple never had any children theirs was a very
close relationship and was it said to be a marriage of "unexampled devotion."
Marriage
Katherine was the daughter of the principal of the college, but despite this,
when Marischal and King's College were combined to form the University of
Aberdeen, Maxwell did not succeed in retaining his post. As a result he
successfully applied for the vacant professorship of Natural Philosophy at
King's College London and he took up the post in 1860.
Maxwell held the post at Kings for six years and it was during his time here
that he undertook his most important work making further investigations into the
properties of the electromagnetic fields he had postulated. He discovered that
they travelled at approximately the same speed as light and proposed that light
was in fact an electromagnetic wave. He also published two classic papers on the
subject.
However he did not confine his researches to electromagnetic theory. He
undertook work investigating the kinetic theory of gasses and as a result of
this a probability function bears his name. This work lead to him presenting a
lecture to the Royal Society in 1866. He had previous been elected tot he
Society in 1861.
Whilst in London he also had the opportunity of meeting and getting to know
Faraday well. An example of their friendship was shown when Maxwell was
attending one of Faraday's lectures. When the density of the crowd leaving the
lecture theatre prevented Maxwell from getting out, the Faraday referring to his
work on gases was heard to say "Ho Maxwell, cannot you get out? If any man can
find his way out through a crowd it should be you!"
At King's College
In 1865 Maxwell resigned his professorship at Kings and retired to his family
estate in Glenair. Most of his time was spent here, and he enlarged the house in
accordance with a plan his father had made. However he still kept some links
with King's College as he served as an external examiner, returning each spring.
He also undertook a tour of Italy with his wife in the spring and summer of
1867. However he kept himself busy in his scientific activities by writing a
major work entitled Treatise on Electricity and Magnetism. It is within this
volume that his four equations are stated. The work that is recognised as one of
the great scientific texts and has a preface in which Maxwell states that his
main aim was to convert Faraday's physical ideas into a mathematical form that
would serve and as explanation of how they occurred. One of the conclusions of
the work was that there was a form of electromagnetic wave and that he could
"scarcely avoid the inference that light consists of the same undulations of the
same medium which is the cause of electric and magnetic phenomena."
Despite the fact that Maxwell was in "retirement", Cambridge University
approached him with the offer of becoming the first Cavendish Professor of
Physics. Somewhat reluctantly he accepted the post in March 1871. However he
soon set about his new responsibilities with relish. As part of his
responsibilities, Maxwell was able to set up a new physics laboratory that was
to be called the Cavendish laboratory. Maxwell was keen to make this a
world-renowned centre and such was his enthusiasm that he even helped in the
design of the laboratory.
Whilst at Cambridge, Maxwell only taught a few students, but these were of
the highest calibre. One of them was Ambrose (later Sir Ambrose) Fleming, the
inventor of the diode valve and professor of UCL. Later he commented that
Maxwell had too much learning and too much originality to be at his best in
elementary teaching. Adding that for those who could follow him his teaching was
a delight.
Last days
Some years later during the Easter term of 1879 Maxwell became ill. His health
had always been somewhat delicate and two years previously he had suffered
digestive problems but had chosen to ignore them. Now his health took a decided
turn for the worse. Despite this he continued to give his lectures up until the
end of the term. After the end of term he returned to Glenair for the summer
with his wife who was also ill. His health steadily deteriorated, and despite
the pain he suffered he remained very cheerful. After the summer he returned to
Cambridge almost unable to walk, and he finally passed away on 5th
November.
It appears that Maxwell had suffered from abdominal cancer, exactly the same
illness that had taken his mother at exactly the same age. His Doctor commented
"No man ever met death more consciously or calmly."
During his life, Maxwell had achieved a considerable amount. His major
contributions are undoubtedly his electromagnetic field theory and the resulting
equations. However he made considerable contributions to many other fields of
science including thermodynamics and the kinetic theory of gases. He also
studied looked at early forms of colour photography, devising some experiments
to show it could work. He contributed to what is known today as information
theory, and there is much more.
In his personal life he was known to have a keen sense of fun and humour,
often playing practical jokes on people and teasing them. Once he mischievously
expounded the difference between Centigrade and Fahrenheit to a group of eminent
scientists.
In life Maxwell had contributed a significant amount to the furtherance of
our understanding of many aspects of science. However he received no public
honours and was buried quietly in a small churchyard at Parton in Scotland.
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