Sir William Thomson, 1st Baron, Lord Kelvin of Largs, eminent mathematician, physicist and inventor, died on the 17th of December, 1907.
William Thomson introduced the concept of absolute zero and the Kelvin scale of temperature measurement was named in his honour as was the unit of thermodynamic temperature. In his work, he brought together many disparate areas of physics, such as heat, thermodynamics (a word he coined in 1849), mechanics, hydrodynamics, magnetism, and electricity. Apart from his important experimental work on thermodynamics and electromagnetism, he invented the mirror galvanometer and contributed to the development of telegraphy. He co-discovered the ‘Joule-Thomson effect’ and, with Faraday, was responsible for the the concept of an electromagnetic field.
Although Thomson was born in Belfast, he had a Scottish mother and, from the age of six, was brought up in Glasgow, which is surely good enough to claim him as Scots. He never went to school, being taught by his father before going to University at the age of ten, a feat for which he appears in the Guinness Book of Records. He also appears on Clydesdale Bank one hundred pound notes. Thomson’s joined-up theories of energy mean that he is to 19th Century physics what Newton was before him in the 17th Century and Einstein afterwards to the 20th.
William Thomson was born on the 26th of June, 1824, in Belfast, just across the water from Scotland. After his mother died, in 1830, his family moved to Glasgow, where, instead of going to school, the young prodigy was taught mathematics by his father, who was himself an engineer and Professor of Mathematics at the University of Glasgow. William attended lectures at Glasgow University from the age of eight and, from the age of ten, together with his eleven years old brother, James, he was enrolled to study at the University. Such attendance was not quite as unusual as you might think, for in those days, Scottish Universities had to compete with Schools for the most able pupils.
William began what we would consider University-level work, in 1838, when he was fourteen and, by the time he was eighteen, he had published several papers. His ‘Essay on the Figure of the Earth’ won him a gold medal from the University of Glasgow when he was fifteen years old. That was a remarkable work, which contained some important ideas that Thomson returned to later in his career. In 1838/9, Thomson studied astronomy and chemistry, and the next year, he took courses in natural philosophy (i.e., physics), studying Fourier’s ‘The Analytical Theory of Heat’. That is a work on the application of abstract mathematics to heat flow, of which Thomson later wrote, “I took Fourier out of the University Library and in a fortnight I had mastered it; gone right through it”.
He graduated in mathematics and natural philosophy from Glasgow and, while still in his teens, pursued a graduate degree in Cambridge and attended the University in Paris. He took the ‘Mathematical Tripos’ examinations and graduated BA from Cambridge at the age of twenty-one. In the next year, 1846, with some help from his father, he was awarded the chair of Natural Philosophy at the University of Glasgow, where he remained for more than fifty years until retiring, in 1899. In his role at Glasgow, he was responsible for the construction of Britain's first physics laboratory.
At Cambridge, Thomson became interested in the French approach to mathematics, encouraged by Babbage and Herschel. Also, whilst in Paris, he worked with Henri-Victor Regnault, and discussed matters of natural philosophy with the likes of Cauchy and Liouville. It was Liouville’s influence that led to Thomson working to unite the ideas of Faraday and Coulomb and studying the whole methodology of a physical science, distinguishing the 'physical' parts of a theory from the 'mathematical' parts. In 1847, Thomson introduced James Prescott Joule's heat theories to the Royal Society and over the next few years worked together on the heat and energy of certain gases. The Joule-Thomson effect was named after their collaboration. This phenomenon means that when a gas is introduced into a vacuum its temperature drops and, if the drop is big enough, the gas is converted to a liquid. Later Scottish scientists would use it as the basis for the liquification of gases, such as hydrogen and oxygen.
Thomson became especially interested in the relationship between the temperature and volume of gases. He worked to prove the theory of the French physicists Sadi Carnot and
Clapeyron and, in 1848, was able to explain the effect. When the temperature of a gas is reduced, so is the energy level of the atoms and as the atoms move less, they take up less room, therefore, decreasing the volume. At -273.16° Celsius, the energy level of the atoms reaches zero and they stop moving, taking up almost no space, and their temperature cannot be lowered any further. Because this theory should be true for any substance, Thomson called -273.16° C the absolute zero of temperature. He then proposed an absolute scale of temperature, which was later given his name and used by James Clerk Maxwell in the formulation of his kinetic gas theory.
Thomson's was always interested in the practical utilisation of science and this led to him adding fortune to his fame. During the late 1800s, much of the British scientific community was busy working on the first transatlantic cable. Thomson’s contribution was to invent a number of ultra-sensitive mirror galvanometers and rescue the project from collapse after the complete failure of the high-voltage methods of the project’s chief engineer. Thomson’s theory was that only very low voltages could transmit the telegraph signals at a sufficient rate over such a long cable. He was proved right and, beginning in 1865, the underwater cable provided instant communication across the Atlantic.
He received due recognition, in 1866, when he was knighted, and took the title of Baron Kelvin of Largs, in 1892, derived from the name of the river that runs through the grounds of Glasgow University and the town of Largs on the Ayrshire coast. His interest in marine issues inspired him to develop a mariners' compass and invent a tide machine and depth-measuring equipment. He invented many electrical instruments and his house in Glasgow was the first to be lit by electric light. During his life, he published more than 600 scientific papers and received dozens of honorary titles and degrees. He was President of the Royal Society and has several lunar features named after him. William Thomson died on the 17th of December, 1907, at Netherhall in Ayrshire, and was buried next to Isaac Newton in Westminster Abbey.