Lewisite (Poison gas)

Lewisite (L) (A-243) is an organoarsenic compound. It was once manufactured in the United States, Japan, Germany and the Soviet Union for use as a chemical weapon, acting as a vesicant (blister agent) and lung irritant. Although colorless and odorless in its pure form, impure samples of lewisite are a yellow, brown, violet-black, green, or amber oily liquid with a distinctive odor that has been described as similar to geraniums. Lewisite is named after the US chemist and soldier Winford Lee Lewis (1878–1943). Lewisite has no applications other than use as a chemical weapon, with a chemist from the United States Army's chemical warfare laboratories stating that "no one has ever found any use for the compound".