A more useful and efficient modification of the low wire entanglement is made by stapling the wire down the sides of the stakes, allowing five or more feet of slack wire between stakes. Drive the stakes in the ground until the top is flush. This results in a loose network of tangled wires difficult to get through, easily concealed, and difficult to remove. The high wire entanglement is made by driving stakes so that they protrude from 4 to 6 feet above the ground. They are placed at irregular intervals 5 to 8 feet apart. The head of each stake is connected with the foot of adjoining stakes with the wire loosely drawn, wound around the stakes and stapled fast. Each center post should be stayed by four wires. There should be a trip wire about 9 inches from the ground all the way across the front and another about a foot from the top of the center posts. Barbed wire may then be hung in festoons throughout the entanglement, with no fixed pattern. To increase the entanglement wire may be stapled to the foot of the posts, as indicated in the paragraph above, before they are driven. Large nails should be driven in the tops of the posts with half their length protruding. A number of the wires in the entanglement should be fastened together where they cross. The wire should be passed through paint, if practicable, to take away the bright color. The posts should be painted the color of the surrounding country. Under the conditions encountered on the western front this work has to be done hastily. It is best, therefore, to limit the first stage of construction to just so many strands as will form a nucleus for the whole entanglement, in order that the area may be covered by an obstacle before interruption occurs. [Illustration: PLATE 4a.—Plan of wire entanglement.] [Illustration: 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. [Illustration: PLATE 5a.—Alarm trap.] [Illustration: PLATE 6.—Portable entanglement. Constructed in the trenches and rolled into position.] The ordinary repairs to entanglements are made under cover of darkness by working parties detailed for the purpose. Iron posts that can be quickly placed in position are advantageous, their disadvantage being that they may retard bullets that would go through the ordinary wooden posts, thus furnishing just that much cover and protection to attacking parties.