If the enemy trenches are close to ours we may run a little narrow sap extending from our fire trench in the direction of the enemy. Great pains are taken to conceal this sap. The excavated earth is placed in sand bags and carried some distance away. At the end of this sap, which may be 3 × 4 feet, we make a cutting sufficiently large to accommodate two men. As a rule the men in this sap, or listening post, as it is commonly called, are connected with the sentry in the fire trench by a long, strong cord. Signals are pre-arranged to give silent warning of any movements on the part of the enemy.
The duties of these men are very exacting and great caution must be observed. They must listen for any underground mining or hammering on the faucet of gas drums. Consequently this is very important work and a great deal depends upon the coolness and intelligence of the men in the listening post. As the work is very nerve racking, reliefs usually take place every hour. A platoon officer may accompany such relief.
The platoon officers on duty have to make up several reports such as: weather report, showing strength and direction of the wind, and situation report, stating particulars of what may have been seen of the enemy, the number of shells fired in our direction, also any results noted from the firing of the German rocket signals. There is also a casualty report showing the number of casualties during the day. Another report is made out for the shortage of equipment, ammunition, bombs, etc.
1. Duties--(a) One officer per company and one N.C.O. per platoon will always be on duty.
(b) By night the officer and N.C.O. on duty will frequently patrol the trench line, to see that the sentries are alert and to inquire whether they have any information to report about the enemy.
(c) The N.C.O. coming on duty will go around and post new sentries with the N.C.O. coming off duty.
(d) The length of each tour of duty will depend on the number of officers and N.C.O.'s available in the company. Normally, each tour should be, by night 2 hours, by day 4 hours, day commencing at morning "stand to" and night commencing at evening "stand to." In inclement weather it may be advisable to reduce the tour to 1 hour.