=New Mask.= About November 1, Major Karl Connell of the Medical Department, National Guard of New York, reported for duty in response to a cablegram that had been sent asking for him by name. It was intended to send him to a British School to learn the art of teaching gas defense. However, learning after a short talk with him that he had been interested in making masks for administering anæsthesia, there was at once turned over to him samples of all the masks in use by both the Allies and the Germans, with a view to getting his ideas for a new mask. Within two or three hours he suggested a new mask having a metal face piece with sponge rubber against the face and with a canister to be carried on the back of the head. At that early date it was realized that a new mask must be invented which would be far more comfortable and give better vision than the British respirators adopted for use. Connell, thirty-six hours after reporting, had so far developed his idea that he was sent to Paris to make the first model, which he succeeded in doing in about three weeks. This first mask was good enough to risk testing in a high concentration of chlorine and while it leaked to some extent it indicated that the idea was sound. The problem then was to perfect the mask and determine how it could be produced commercially on the large scale necessary to equip an army. Since the British at this time and practically throughout the war were much ahead of the French in all phases of gas warfare, Connell was sent to London. There he succeeded in getting additional models in such shape that one of them was sent to the United States during the first few days of January, 1918. Connell’s work and experiments were continued so successfully that after a model had been submitted to the General Staff, as well as to General Pershing himself, one thousand were ordered to be made early in May with a view to an extensive field test preparatory to their adoption for general use in the United States Army. In this connection, during November, 1917, a letter was written to the United States stating that while the Gas Service in France insisted on the manufacture of British respirators exactly as the British were making them, they desired to have experiments pushed on a more comfortable mask to meet the future needs of the Army.