Для чего нужна была эта штука?
*Ничего военного
К сожалению, никто не отгадал.
Here is a pictured Hugo Gernsbach, wearing what he calls his "isolator," an invention that kills noise. That infernal racket in the shop, office or street, noises jar on the nerves, thus affecting the entire body. This device, which is somewhat extreme yet very practical, would eliminate all such disturbances. The lettered photo diagram describes the composition of the helmet, which is provided with an oxygen tank and tube through which the wearer breathes.