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
British home army in the First World War the New Army over the Territorial Force. Fear of invasion persisted throughout the first months of the war; Kitchener's decision was motivated in part by his concern that the Territorial Force should not be diverted from what he regarded as its primary task of defending the homeland. German success on the continent in September and October opened up the prospect of the French channel ports being used to launch an invasion that could outflank the main British coastal defences north of the Thames. To allow rapid redeployment of the Central Force across the river, construction was begun on a pontoon