Heavy bombing posts are located on the flanks of the crater. The position of these posts is usually at the point of change of direction of the old firing line with the new one of the re-entrant angle. Dugouts may be constructed close to these bombing posts for the protection of the grenadiers during the explosion. Immediately the explosion is over, these grenadiers man their posts and establish a heavy barricade between the posts and the crater by using hand grenades. If the enemy attempts to enter the crater, these grenadiers can make it untenable by throwing hand grenades into it.

Automatic rifle or machine gun emplacements are also located on both flanks of the crater. Their function is to establish flanking fire on hostile troops attempting to approach the crater.

Rifle grenadiers are stationed in the line of trenches to establish a defensive rifle barrage out in front of the crater.

The riflemen will usually occupy the near and flank lips of the crater. They will not occupy the lip of the crater nearest the enemy until it is ascertained that the enemy has no more galleries.

A rocket post is located in the first line on the flanks of the crater. As soon as the crater is exploded, a rocket is sent up from this post calling upon the artillery for a defensive barrage. Usually, special artillery is detailed for this extra fire. It is a reinforced fire, or a combination of preventive fire and protective barrage. It is established on the enemy’s first line rather than in “No Man’s Land” as a purely defensive barrage.

With all these precautions taken, the infantry await the explosion of the mine.

A Selection from the Catalogue of

G. P. PUTNAM’S SONS

Complete Catalogue sent on application