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le chlore fit place au phosgène et au diphosgène encore plus mortels; on lançait sur les soldats des poussières et des gaz sternutatoires ou expectorants pour les obliger à enlever leurs masques à gaz afin qu’ils soient victimes de gaz mortels.
chlorine was replaced by the deadlier phosgene and diphosgene; and sneezing and choking gases and dusts were introduced to force soldiers to remove their respirators so that they would fall victim to lethal agents.