ABSTRACT
Chemicals, mainly in the form of vapors and smokes, have been used by man from early times for protective (by incapacitating) and offensive purposes (SIPRI, 1971). One of the earliest smokes was a burning mixture of pitch and sulfur (Greek fire) which was thrown at enemies to discourage them by virtue of its irritant effects. Arsenical smoke was used by Hunyadi to defend Belgrade against the Turks in 1456, and soldiers of the Bishop of Munster also used arsenical projectiles in 1672 as a siege weapon against Gronigen. Plutarch is said to have described an action by a Roman general in Spain in which an irritant cloud was used to drive enemy out of concealment in caves. This practice was also used in the late-twentieth century for cave and tunnel denial in Vietnam, and led to strenuous denials that this use of tear gas is chemical warfare in the context of the Geneva protocol.
