Chemical weapons in World War I in Palestine during the Second Battle of Gaza. Russia began manufacturing chlorine gas in 1916, with phosgene being produced later in the year. Most of the manufactured gas was never used. The British Army first used mustard gas in November 1917 at Cambrai, after their armies had captured a stockpile of German mustard gas shells. It took the British more than a year to develop their own mustard gas weapon, with production of the chemicals centred on Avonmouth Docks. (The only option available to the British was the Despretz–Niemann–Guthrie process). This was used first in September 1918 during the breaking
Tanks in the German Army the Anglo-Canadian forces of the 21st Army Group; and the numerous battles to secure the town became collectively known as the Battle of Caen. US forces in the meantime, engaged mainly the "Panzer Lehr" Division, and the Panther tank proved to be most effective when fighting in open country and shooting at long range—its combination of superior armor and firepower allowed it to engage at distances from which the American M4 Shermans could not respond. The Tiger was first used in action on 23 September 1942 near Leningrad. Under pressure from Hitler, the tank was put into action months earlier