They are not expected to know all the details of gases and their uses, but they will be expected to consider the use of gas in every phase of preparing plans and orders and then to appeal to the chemical warfare officers for the details that will enable them to use the proper gases and the proper quantities. They cannot go into those details any more than they can go into the details of each company of infantry. If they try to do that they are a failure as staff officers. =Effect of Masks on Troops.= The very best of masks cause a little decrease in vision, a little increase in breathing resistance, and a little added discomfort in warm weather, and hence the soldier must learn to use them under all conditions. But above all in the future he must be so accustomed to the use of the mask that he will put it on automatically—almost in his sleep as it were. We have tear gases, today, so powerful and so sudden in their action that it is doubtful if one man out of five who has had only a little training can get his mask on if subject to the tear gas alone—that is, with tear gas striking him with full force before he is aware of it. =Effectiveness of Gas in World War.= In the past war more than 27 out of every 100 Americans killed and wounded suffered from gas alone. You may say that many of the wounds were light. That is true; but those men were put out of the battle line for from one to four months—divisions, corps and armies almost broken up—and yet the use of gas in that war was a child’s game compared to what it will be in the future. It is even said that many of them were malingerers. Perhaps they were, but do you not suppose that there were at least as many malingerers among the enemy as there were in our own ranks? Furthermore, if you can induce malingering it is a proper method of waging war, and unless our boasted ability is all a myth we should have fewer malingerers under conditions of battle than any other nation. =Strategy of Gas at Picardy Plains.= Let us go back now to the strategy of gas in war. Following the cloud gas came tear gases and poisonous gases in shells and bombs. A little advance in tactics here and a little there, the idea, though, in the early days being only to produce casualties. As usual the Germans awoke first to the fact that gas might be used strategically and on a large scale. And thus we find that ten days before he began the battle of Picardy Plains he deluged many sections of the front with mustard gas. He secured casualties by the thousands, but he secured something of greater importance. He wore out the physical vigor and lowered the morale of division after division, thus paving the way for the break in the British Army which almost let him through to the sea.