1-624-107 - The Print Collector/Heritage Images

William Thomson, Lord Kelvin, Irish-Scottish mathematician, physicist and engineer, (20th century). Kelvin (1824-1907) was a leader in the physical sciences of the 19th century. He did important work in the mathematical analysis of electricity and thermodynamics, and did much to unify the various theories of heat held by leading scientists of the time. Kelvin introduced the Kelvin or absolute scale of temperature, and discovered the Thomson effect in thermoelectricity. Also significant are his discoveries and improvements in the field of communication via submarine cables, and his invention of the reflecting galvanometer and the siphon recorder.