(a) Maintenance: The daily work of maintaining the elements of the position is considerable, and its importance often escapes those responsible for the same. They are:

Repair of parapets, boyaux, and shelters damaged by bombardment, water, or frost.

Replacing or completing accessory defenses, revetments, ammunition recesses, emplacement of machine guns, observation posts, depots, etc.

Cleaning and Draining of Trenches and Boyaux: The garrison of each area is responsible for their own maintenance work, which is done usually during daylight hours. Sometimes during severe bombardments this repair and maintenance work becomes too great for the garrison and workmen have to be called in to help.

(b) New Construction: New elements of the position are constructed in carrying out the Plan of Organization. These are usually carried out at night. This work is carried out by troops in the doubling trench, the support line, or detachments of workmen from the reserve of the sector. There may also be special parties from the headquarters detachment of pioneers or of the engineer battalion of the brigade.

For all these special works the personnel for whom they are built must be present during the construction to furnish necessary information and for inspection. A machine gun crew helps in building its emplacement; the intelligence officer directs the construction of his observatories. The medical officer present during the work on the medical aid station; the telephone officer superintends the establishment of his telephone exchange, etc.

The battalion commander is responsible for all the work done in his center of resistance, and in conjunction with the sector leader draws up a time-table for the work.

All this work must be continued by each succeeding relief. When a new unit takes its turn in the trenches the orders and plans of new works are turned over to its commander.

Arms, Equipment, and Ammunition. Full equipment will always be worn in the firing trench, except the haversack, water bottle, and entrenching tool. In the support and reserve trenches the equipment to be worn is subject to the will of the sector commander. Every man will always carry a gas mask in any part of the position and even as far to the rear as ten miles.

The men in the firing line and in the doubling trenches will at all times be in possession of their rifles and bayonets. The rifles of men in the support and reserve trenches may be kept in protected racks in the same shelter as the men.