Lord Kelvin

William Thomson, later known as Lord Kelvin, was a Scottish mathematician, physicist, and engineer born in Belfast on 26 June 1824. For 53 years, he held the chair of Natural Philosophy at the University of Glasgow, where his work focused on the mathematical study of electricity and helped shape the first and second laws of thermodynamics. His efforts were key in bringing together different branches of physics at a time when the field was just emerging as a formal discipline. He was awarded the Royal Society’s Copley Medal in 1883 and later served as the society’s president from 1890 to 1895. In 1892, he became the first scientist to be made a member of the House of Lords.

The unit of absolute temperature, the kelvin, is named after him. Although scientists already knew that a lowest possible temperature—absolute zero—existed, Kelvin was the one to calculate its precise value: roughly −273.15 degrees Celsius or −459.67 degrees Fahrenheit. The Joule–Thomson effect also bears his name.

Kelvin collaborated closely with mathematics professor Hugh Blackburn. Beyond academia, he worked as an electrical telegraph engineer and inventor, a career that brought him public fame, wealth, and honors. For his role in the transatlantic telegraph project, Queen Victoria knighted him in 1866, making him Sir William Thomson. He also had strong maritime interests, notably improving the mariner’s compass, which had been notoriously unreliable.

His elevation to the peerage in 1892—becoming Baron Kelvin of Largs in the County of Ayr—recognized his contributions to thermodynamics as well as his opposition to Irish Home Rule. The title refers to the River Kelvin, which runs near his laboratory at the University of Glasgow’s Gilmorehill campus. Despite offers from prestigious universities around the world, Kelvin refused to leave Glasgow, remaining there until his retirement in 1899. He stayed active in industrial research and, around 1899, was recruited by George Eastman to serve as vice-chairman of the board of the British company Kodak Limited, an affiliate of Eastman Kodak. In 1904, he became Chancellor of the University of Glasgow.

Kelvin lived at Netherhall, a mansion in Largs that he built in the 1870s, and died there in 1907. The Hunterian Museum at the University of Glasgow maintains a permanent exhibition on his work, featuring original papers, instruments, and personal items, including his smoking pipe.

Thomson was born in Belfast on 26 June 1824. His father, James Thomson, taught mathematics and engineering at the Royal Belfast Academical Institution and was the son of an Ulster Scots farmer. James married Margaret Gardner in 1817; they had six children who survived infancy. Margaret died in 1830, when William was six. William and his older brother James were taught at home by their father, while the younger boys learned from their older sisters. The elder James was groomed for engineering and received the bulk of their father’s attention and financial support.

In 1832, James Thomson became a mathematics professor at the University of Glasgow, and the family moved there in October 1833. The children were exposed to a wider world than their father’s rural background: they spent mid-1839 in London, and the boys studied French in Paris. Much of Thomson’s time in the mid-1840s was spent in Germany and the Netherlands, with language study a priority. His sister Anna later became the mother of physicist James Thomson Bottomley.

Thomson attended the Royal Belfast Academical Institution, where his father taught. In 1834, at age ten, he began studying at the University of Glasgow—not because he was unusually advanced, but because the university offered elementary-level classes for able pupils, and this was a typical starting age. He showed a strong interest in classics as well as science. At twelve, he won a prize for translating Lucian’s *Dialogues of the Gods* from Ancient Greek into English.

During the 1839–1840 academic year, he won the astronomy class prize for an essay on the figure of the Earth, which demonstrated early mathematical skill and creativity. His physics tutor at the time was David Thomson. Throughout his life, Thomson returned to the problems raised in that essay as a way to cope with personal stress. On the essay’s title page, he quoted lines from Alexander Pope’s “An Essay on Man,” which inspired him to understand nature through science.

Thomson became fascinated by Joseph Fourier’s *Théorie analytique de la chaleur*. He committed himself to learning the “continental” mathematics that the British scientific establishment, still under Newton’s shadow, resisted. Fourier’s work had been attacked by British mathematicians, including Philip Kelland, who wrote a critical book. That book prompted Thomson to write his first published scientific paper, under the pseudonym P.Q.R., defending Fourier. His father submitted it to *The Cambridge Mathematical Journal*. A second P.Q.R. paper followed quickly.

While on a family holiday in Lamlash in 1841, he wrote a third, more substantial P.Q.R. paper, “On the uniform motion of heat in homogeneous solid bodies, and its connection with the mathematical theory of electricity.” In it, he drew remarkable connections between the mathematics of heat conduction and electrostatics—an analogy that James Clerk Maxwell would later describe as profound.