I suppose that somebody worked out that chlorine was neutralised by urine - don't know the chemistry behind that. Mind you if you were sitting in a trench with a cloud of chlorine coming towards you I expect you'd try anything.
http://www.historylearningsite.co.uk/poison_gas_and_world_war_one.htm
Not a pleasant experience.
http://www.historylearningsite.co.uk/poison_gas_and_world_war_one.htm
Not a pleasant experience.