show later; but they added nothing to the direct process of destroying life. Gas seemed by all odds the most promising of the new weapons. That simple chlorine which the Germans used in 1915 gave place to other gases more complex and more destructive to human body-cells. At first released only in clouds and dependent upon a favorable wind for their effect, the chemicals which generated these gases were later loaded into shells and projected miles beyond any danger to the army which employed them.
As gas improved, so did the defence against it. The crude mouth-pads, consisting of a strip of gauze soaked in “anti-chlorine” chemicals, which the women of England rushed to the Front after Second Ypres, were succeeded by more secure and cumbersome masks. The standard mask worn by the Americans in 1918 was a complex machine. It was cleverly constructed to fit the face air-tight; its tank held antidotes for all known German gases. However, this was an imperfect protection, because men could not or would not wear it all the time. It took the sternest discipline to make troops keep on their masks even in time of danger. Surprise gas-bombardments were always catching them unmasked. A slight leak was fatal. In that stage of chemical warfare, the losses from gas-shells in proportion to the quantity used, were at least as great as those from high-explosive shells.
Yet the mask was a protection; let us therefore
