The breastwork hastily erected by the Arabs across the end of the causeway was neither long enough nor strong enough. But along the shore of the island ran a low artificial embankment against floods. Just behind it was an old, much dilapidated wall. About a hundred and fifty yards on the right of the causeway the embankment had broken away. It was only necessary to break an opening in the wall just behind this gap, to form a sort of embrasure for the gun. The position was well screened from the enemy, for the surface of the island rose slightly in the rear, and the horizon, from the Turks' point of view, was cut by the chief's tower with the dwarf trees that flanked it. Placed in this embrasure, the machine-gun would command the whole of the causeway except the fifty yards nearest the island. It was a question whether the necessary pioneer work could be done during the hours of daylight, for much of it must be carried out in full view of the enemy. But at present none of the Turks was to be seen. They were not at work on the causeway, and a careful scanning of their farther position through field-glasses failed to detect any sign of movement or of preparations. Taking advantage of this rather surprising inactivity, which suggested that they were either awaiting reinforcements or planning some dangerous stroke, Burnet set a large number of the Arabs to the task of carrying out his scheme. While some cut the embrasure for the machine-gun, others dug a communication trench from the blockhouse to a group of ruins about two hundred yards in the rear. Others again strengthened these ruins by piling up blocks of masonry collected from the whole area, so as to form a shelter, effectual against all but gun fire, for the larger part of the garrison. The underground chambers beneath the ruins were partially cleared of accumulations of rubbish, and should serve as safe quarters when the men were not in action. While Burnet was setting all these operations in train, Rejeb had superintended the departure of the non-combatants. They were transported in relays across the southern marshes on the kelak. The horses, too, under the charge of a score of well-armed men, left the island by wading or swimming, Rejeb keeping half a dozen in a safe place at the south of the island, in case he might find them useful for scouting. Among them were his own horse, and the one that Burnet had captured.