Chemical weapons in World War I volatile oily liquid. It was introduced as a vesicant by Germany in July 1917 prior to the Third Battle of Ypres. The Germans marked their shells yellow for mustard gas and green for chlorine and phosgene; hence they called the new gas "Yellow Cross". It was known to the British as "HS" ("Hun Stuff"), and the French called it "Yperite" (named after Ypres). Mustard gas is not an effective killing agent (though in high enough doses it is fatal) but can be used to harass and disable the enemy and pollute the battlefield. Delivered in artillery shells, mustard gas was
Tanks in the German Army the main battle tank in over a dozen countries worldwide, but the German Leopards never saw combat. In the German Army, the Leopard 1 MBTs have been phased out in 2003 while Leopard 1 derived vehicles are still widely used. The Leopard 2 MBTs have taken over the MBT role and first entering service in 1979. The Leopard 2 have served in the armed forces of Germany and twelve other European countries, as well as several non-European nations. More than 3,480 Leopard 2s have been manufactured. The Leopard 2 first saw combat in Kosovo with the German Army and has