The recesses should be about 8 feet long and at least 2 feet wide, and the soil excavated from these recesses could be used for strengthening the parapets of the C. T.’s at these turns. Generally, when time allows and energy permits, close to the firing line these recesses are made longer and deeper, oftentimes running to 12 and 18 feet long by 6 and 10 feet deep, although it is not advisable to crowd them too much. Recesses of this kind may also be heavily roofed and used as a very temporary shelter for stretcher cases, stores of bombs, ammunition, etc. At every second or third stretch in these C. T.’s, either steps or an easy runway to the top of the trench should be made. This saves time on a great many occasions when parties coming over the top for speed and comfort find themselves stopped and have to take to the trench on short notice. It is also good when a serious obstruction occurs, and it is necessary to leave a C. T. and enter it again farther on. NOTICE BOARDS These boards should be fixed at every entrance and junction in a trench system, stating the name of the trench and the places to which it leads, and where there are trenches expressly for up and down traffic, these boards should state it. Some people argue that such notices assist the enemy when they get into our trenches, but the argument does not hold as it is very often the case they do not know the names used in the sectors, as they vary up and down the line, and generally they have a very good idea of the system they will find themselves in anyway, and there is a very small chance that a majority of them will be able to read them anyway. Care must be taken that these notice boards are not used for what is known as “boiling up,” building fires, in braziers, etc., as the absence of these boards causes a tremendous amount of confusion when new troops are coming into the line. All officers must know the shortest routes from their own headquarters to those of companies on their flanks, as well as their own battalion headquarters, and every officer, N. C. O. and man must know the position of his immediate commander’s dugout, as well as his company headquarters, and every man must know the name of the trench that he is in and helping to hold, and this is not possible when these notice boards are destroyed. TRENCH DRAINAGE