Dewar, James

Scottish chemist and physicist who invented the vacuum flask (Thermos) in 1872 during his research into the properties of matter at extremely low temperatures. He was knighted in 1904.

Working on the liquefaction of gases, Dewar dicsovered, in 1891, that both liquid oxygen and ozone are magnetic. In 1895 he became the first to produce liquid hydrogen, and then in 1899 succeeded in solidifying hydrogen at a temperature of -259°C/-434°F. He also invented, jointly with Frederick Abel, the explosive cordite in 1889.