These helmets were changed in the course of a week or two for the more efficacious box Respirators, which remained with slight modifications until the end of the war as the soldiers' protection against enemy gas.
"The Story of the "9th King's" in France"
Enos Herbert Glynne Roberts
"By the time the outer atmosphere really begins to show the effect of withdrawing a considerable percentage of the oxygen," Flint answered, "we will have our pocket Respirators on the market.
"The Air Trust"
George Allan England
Well-to-do people will as soon think of going out without their shoes, as they will with their Respirators.
"The Air Trust"
George Allan England