Efforts at drainage, which is the greatest trouble during the winter months to troops occupying the line, must be as systematic and thorough as possible. Tinkering is of very little use and brings no results but causes a great and tiring expenditure of labor as far as the men are concerned, with no end of work in sight. When taking over a sector of line, the drainage system must be thoroughly studied and a line of campaign mapped out and strictly adhered to. Thorough work in the initial stages will save any amount of subsequent unnecessary fatigue and labor. The system to be applied depends entirely on local conditions, but full advantage must be taken of the assistance which nature affords. Water running down hill is a marvelous fact; nevertheless it is often overlooked. Field drains and natural streams anywhere near the trench must be kept clear of obstructions. These are usually attended to by the overworked farmers in peace times, but as they do not work near a trench system, it must be looked after by the army. Neglect of the natural watercourses has been the cause of much of the difficulty of draining the trenches themselves. During the winter months a trench is never really drained. A mixture in the trenches which is neither water nor good, sticky mud, but a beautiful liquid combination of water and dirt, which is thick enough not to run, is formed. Sometimes it becomes sufficiently like water to be pushed or assisted to run down hill with scrapers, boards, and anything else that is handy. Sometimes it becomes sufficiently heavy enough to be shoveled over the parapet or put into sand bags. In either of these cases it is only overcome by persistent labor, but when the mud is in its true clayed self it is a waste of time and labor to attempt to move it, and the only way, without a large amount of cursing, is to sit tight and pray for the sun to dry it.