William Thomson, 1st Baron Kelvin
William Thomson, 1st Baron Kelvin, 1st Baron (1824-1907). Scottish scientist. Kelvin was professor of natural philosophy at Glasgow University from 1846 to 1899. He undertook research into electricity, magnetism, heat, and elastic ity, earning a knighthood (1866) for his work on the transmission of electric current in telegraph cables. His work in thermodynamics enabled him to define the absolute scale of temperature and the units of the scale were named after him. He was elevated to the peerage in 1892.