Gas
The German army were the first to use chlorine gas at the battle of Ypres in 1915. Chlorine gas causes a burning sensation in the throat and chest pains. Death is painful - you suffocate! The problem with chlorine gas is that the weather must be right. If the wind is in the wrong direction it could end up killing your own troops rather than the enemy.
Mustard gas was the most deadly weapon used. It was fired into the trenches in shells. It is colorless and takes 12 hours to take effect. Effects include: blistering skin, vomiting, sore eyes, internal and external bleeding. Death can take up to 5 weeks. By the end of the war, both sides were using chemical gas and both sides were providing their soldiers with gas masks in hopes of preventing painful deaths.
Mustard gas was the most deadly weapon used. It was fired into the trenches in shells. It is colorless and takes 12 hours to take effect. Effects include: blistering skin, vomiting, sore eyes, internal and external bleeding. Death can take up to 5 weeks. By the end of the war, both sides were using chemical gas and both sides were providing their soldiers with gas masks in hopes of preventing painful deaths.