Scottish physicist William Thomson, knighted as Lord Kelvin, (1824-1907), devised his absolute temperature scale based on the Celsius scale. The size of a Kelvin is the same as the size of a degree Celsius.

Thomson was a great friend of James Prescott Joule, who discovered that heat can be changed into work and vice versa. Thomson set out to support Joule's theory. He developed the first ever physics lab in Great Britain at the University of Glasgow, to experiment with heat and gases. It was this work that led him to devise the Kelvin scale, based on Celsius-sized degrees. His absolute scale began at absolute zero, -273°C. Baron Kelvin contributed to the study of many sciences in his day. He began his college studies at age 11. Kelvin published 661 scientific papers and patented 70 inventions. Queen Victoria knighted Thomson (as Lord Kelvin, first Baron of Largs) for his work on the electrical engine. Kelvin was in charge of laying the first successful transatlantic cable in 1866. Baron Kelvin was one of the first to strongly suggest use of the metric system. In scientific meetings, he would denounce the 'absurd, ridiculous, time-wasting, brain-destroying British system of weights and measures.' It is a tribute to him that the Kelvin is now one of the seven fundamental units of the metric system. Scientists use the Kelvin scale on a worldwide basis today.