Every officer defending a trench against an enemy gas attack should endeavor to collect information whenever possible, to be sent to headquarters through the usual channels. Particularly valuable is the capture of apparatus used by the enemy either for disseminating gas or for protection against it. If a shell attack is made, unexploded shells or portions of them should be sent through to headquarters at once. The time of day, duration of attack, color, taste or smell of gas used, effect on the eyes, breathing, and all other symptoms should be noted. New gases may be used at any time, and speedy information greatly forwards the adoption of preventive measures. CHAPTER X SERVICE IN THE TRENCHES PREPARATIONS FOR ENTERING TRENCHES Preparing to enter upon a period of service in the trenches the company commander makes a complete inspection of the company which includes: 1. Inspection of rifles and ammunition. 2. Inspection of equipment, contents of packs, intrenching tools, field glasses, wire cutters, first-aid packets, emergency rations, gas helmets, identification tags, canteens, clothing, etc. 3. Canteens to be filled with water. 4. Test bayonets, fix and unfix. 5. Have company fill magazines. INSPECTION OF SECTION The company commander precedes the company into the trenches and makes a tour and inspection of the section assigned, which includes: 1. Layout of the trenches: fire trench, supervision trench, communication trenches, machine-gun positions, snipers' positions, listening and observation trenches, dugouts, latrines, etc. 2. Locate telephones, reserve ammunition and munitions depots, water supply, gas alarms, tools and any trench accessories and utilities that may be included in the section. 3. Get any information of the enemy that may be of value from the outgoing company commander. TACTICAL DISPOSITION The company commander will then make his tactical dispositions. In occupying the trenches a certain section of the line is assigned to each company. This section contains so many bays of the trench. The following dispositions are suggested as meeting the requirements under our organization: 1. The company is organized into four platoons of four squads each. 2. The section of the line assigned to the company contains eight bays. 3. Support No. 1 consists of the first and second platoons. 4. Support No. 2 consists of the third and fourth platoons. 5. From Support No. 1: Two squads of the first platoon occupy bays 1 and 2; two squads of the second platoon occupy bays 3 and 4. [Illustration: PLATE 41_a_. TACTICAL DISPOSITIONS ONE COMPANY OF INFANTRY.] 6. From Support No. 2: Two squads of the third platoon occupy bays 5 and 6; two squads of the fourth platoon occupy bays 7 and 8.