In each trench there must be dugouts for the men to sleep in. The first ones that are made will be very primitive, and will be very much like a fireplace in a room--simply excavations in the back wall of the trench almost on a level with the bottom of it. At first they used to be dug in the front of the trench, but this practice was discontinued as it was found to weaken the power of resistance of the very important parapet. In the course of time more labour can be expended upon the dugouts, and it will be found advisable to construct them of uniform size, six feet long by four feet wide by four feet high. By having them uniform we give the engineers a chance to make frames that can be used to support the roof and the sides and bring them well from the rear to construct the dugouts. These dimensions do not make a very commodious home for four men, but never more than three of a section (of four) are off duty at the same time, and besides there is considerable danger in having large dugouts, as they present a correspondingly larger target for the guns. A direct hit on a large dugout will often bring the whole thing crashing about the ears of the inhabitants. My own adjutant and one of my brother officers were killed by falling beams in large dugouts. The entrance to the dugouts must be kept as small as possible so as to protect the occupants from shells that fall just outside. The Germans used to follow the custom of digging many of their "funk holes," as they were called, many feet underground. Sometimes they went down twenty and even thirty feet. The idea of this was that they could retreat into these secure places during a bombardment and then emerge with their machine guns as soon as the attacking infantry had started to approach over "No Man's Land." We never followed that custom, for while it will work at times, yet the attacking infantry may be upon you before you are aware of it and have you at their mercy with bayonets and bombs from the parapet. This the Germans have learnt to their cost many times on the Somme.