Gas was employed in offensive operations in many and varied ways and these and defensive measures were so important that the necessity for a new division of military activities resulted in the organization of the Chemical Warfare Service in the summer of 1918. Five months old at the end of hostilities, the Service then contained 1,600 commissioned officers and 18,000 men. Defensive measures also had been rushed steadily forward, investigation and experiment had produced a better and more comfortable gas mask than was in use and a big Government gas defense plant had been built, equipped and started upon production with skilled workers. The monthly production of gas masks in the autumn of 1918, of which this plant made the major part, had reached 925,000. The total production for the year and a half was over 5,000,000, with 3,000,000 extra canisters, 500,000 horse masks and large quantities of ointments, antidotes and suits for protection against enemy mustard gas. The American gas mask was recognized by all the war associates as the best on the Western front. In the Chemical Warfare Service at the end of hostilities were 1,700 chemists from civil life who had worked steadily to aid in its rapid and efficient development. Under the furious goad of war the Service succeeded in reducing the cost of phosgene gas from $1.50 to 15 cents per pound and therefore increasing very greatly its usefulness in various industries, especially that of dyestuffs. The record of development and production in chemistry is one of the fairly amazing war achievements of this country and is replete with possibilities for the peaceful uses of industry.