Plate 5.—High wire entanglement.

Tight wires help the enemy's advance by forming supports for hurdles. It must be constantly borne in mind that the wires must not be stretched taut.

A portable wire entanglement is constructed by stretching wire loosely around a wooden framework, either circular or square or made on a knife rest, and rolling it into position to close up gaps that may have been made in the entanglement. The illustration shows the wooden framework.

Plate 5a.—Alarm trap.