These are usually made in C.T. to allow for the passing of troops or bearers of stretchers, or parties passing up and down to the line carrying the many things that are necessary for the upkeep of that line.

It is advisable that these should always be placed in the same corresponding place in each stretch, as shown in Section III, just before the turn, so that men know where they are to be found. The first man of a party coming up having arrived at a turn, and seen or heard others coming down, can give necessary protection to his party, and a great deal of unnecessary and very exasperating and fatiguing movements, and sometimes retracing of steps, is avoided. It is also often the cause of a great many casualties in a trench where these recesses are not made, as parties of men coming and going very often, while struggling to get past one another with their loads, are caught by heavy shell fire.

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.