GAS-MASKS
As the different kinds of gas shell were developed, the gas-masks were improved to meet them. In every attack there were "duds" or unexploded shell, which the chemists of the Allies analyzed. Also, they were constantly experimenting with new gases, themselves, and often could anticipate the Germans. The Allies were better able to protect themselves against gas attacks than the Germans, because there was a scarcity of rubber in Germany for the manufacture of masks. When it was found that phosgene was going to be used, the simple cotton-wad masks had to give way to more elaborate affairs with chemicals that would neutralize this deadly gas. And later when the mustard gas was used which attacked the eyes, and the sneezing-gas that attacked the nose, it was found necessary to cover the face completely, particularly the eyes; and so helmets of rubber were constructed which were tightly fitted around the neck under the coat collar. The inhaled air was purified by passage through a box or can filled with chemicals and charcoal made of various materials, such as cocoanut shells, peach pits, horse-chestnuts, and the like. Because the Germans had no rubber to spare, they were obliged to use leather, which made their masks stiff and heavy.