(b) Concealment is easier.
(c) From their nature, it is difficult for the enemy to estimate, for a given length, the number of men sheltered.
They possess, however, certain disadvantages:
(a) The protection is sometimes so excellent that, morally as well as materially, it becomes difficult to leave the shelter. Example: quarries with obstructed exits. Therefore, good judgment must be exercised in the selection.
(b) Some of them are too visible. Example: large hedges. In this case their range can be easily found.
As a general rule, do not occupy them uniformly and do not change the appearance of the organized parts.
Organization of the cover:
To organize the cover which protects troops from fire, construct suitable positions for firing and resting. To utilize the screens which merely hide the troops without protecting them from fire, dig trenches behind these screens in the following manner:
(a) Choose the points which give the best field of fire.