We left the trio next for duty in process of disappearing behind the planks, and about to start on their three-hour shift at the face of the tunnel. Let us keep company with them awhile at their difficult and absorbing task. Tunnelling had at least one great advantage over other methods of escape, that the interest attaching to the actual preparation was able to over-ride, to some extent, the suspense and anxiety as to ultimate success. There was no opportunity to mope. The immediate business was to defeat not only the Boche but Nature too, with all the odds on the latter’s side. The bolting of the wooden partition behind the last of the trio shuts out the day and adds the proper molish touch to the scene. However, what at first appears pitch dark becomes gradually less so, and presently the party can see enough to change their more or less clean orderlies’ clothes for the filthy, sodden, mud-stained rags which they wear for work in the tunnel. There are other minor discomforts besides the darkness and the damp. There is an indescribable musty smell produced by a mélange of damp clay and earth, mice, old clothes, and much-breathed air, a smell which you have to go down into the bowels of the earth to get. The working clothes are soon on, the clean orderlies’ clothes stowed carefully away, and a move is made to the tunnel mouth. Look at the plan on p. 73 and glean a rough idea of the shape of the chamber and the siting of the tunnel mouth. The ground area is roughly four yards by five. The height varies, for, on the near (Kommandantur) side, the roof consists of the concrete foundation to the first flight of the orderlies’ staircase, while on the far side—that next to the Eastern wall of the building—are the cellar steps. The ground level, which is also the roof level at the southern end, is about five feet above the chamber floor. Into the available recesses formed by this irregular enclosure all the tunnel earth must be stowed away. The hollow under the cellar steps is already full, and so will be the opposite hollow under the orderlies’ staircase before the end is reached, for a 60-yard passage through the earth must be displaced somewhere, and it will be a near thing and will require the most careful and economical storage if the displacements can be kept within the narrow cubic space which is all that can be earmarked for them. A passage from the partition door to the tunnel mouth must be preserved at all costs. The tunnel mouth has been hacked through the main southern wall of the building just where it joins the cellar floor. It issues about three feet below the ground level—immediately underneath the orderlies’ entrance—and then bears sharp left in the direction of the outer wall.