From the 1930s through the 1970s, both in Europe and in North America, trichloroethylene was used as a volatile anesthetic almost invariably administered with nitrous oxide. Marketed in the UK by ICI under the trade name Trilene it was coloured blue (with a dye called waxoline blue) to avoid confusion with the similar smelling chloroform. TCE replaced earlier anesthetics chloroform and ether in the 1940s, but was itself replaced in the 1960s in developed countries with the introduction of halothane, which allowed much faster induction and recovery times and was considerably easier to administer. Trilene was also used as a potent inhaled analgesic, mainly during childbirth. It was used with halothane in the Tri-service field anaesthetic apparatus used by the UK armed forces under field conditions. As of 2000, however, TCE was still in use as an anesthetic in Africa.