Two companies of the First Gas Regiment would have been ready in 48 hours to put off a projector attack against an excellent target just west of Belleau Wood had not the 2d battle of the Marne opened when it did. It is said that General Foch had kept this special attack so secret that the First American Corps Commander knew it less than 48 hours prior to the hour set for its beginning. Certainly the Chief of the Gas Service knew nothing of it until about 9:00 P.M., the night of July 17th. Consequently the gas attack was not made. At that time so little was known of the usefulness of gas troops that they were started on road work. At Colonel Atkisson’s suggestion that gas troops could clean out machine gun nests, he was asked to visit the First Corps headquarters and take up his suggestion vigorously with the First Corps Staff. =Attacking Machine Gun Nests.= Thereupon the Gas troops were allowed to try attacking machine gun nests with phosphorus and thermite. This work proved so satisfactory that not long afterwards the General Staff authorized an increase in gas troops from 18 companies to 54 companies, to be formed into three regiments of two battalions each. The 6 companies in France did excellent work with smoke and thermite during all the second battle of the Marne to the Vesle river, where by means of smoke screens they made possible the crossing of that river and the gaining of a foothold on the north or German side. With the assembling of American troops in the sector near Verdun in September, 1918, the gas troops were all collected there with the exception of one or two companies and took a very active part in the capture of the St. Mihiel salient. It was at this battle that the Chemical Warfare Service really began to handle offensive gas operations in the way they should be handled. Plans were drawn for the use of gas and smoke by artillery and gas troops both. The use of high explosives in Liven’s bombs was also planned. Those plans were properly co-ordinated with all the other arms of the service in making the attack. Gas was to be used not alone by gas troops but by the artillery. Plans were made so that the different kinds of gases would be used where they would do the most good. While these plans and their execution were far from perfect, they marked a tremendous advance and demonstrated to everyone the possibilities that lay in gas and smoke both with artillery and with gas troops.