Next day Burnet resumed his own uniform and went round the position with Rejeb. It appeared that when the non-combatants were gone, under escort of a sufficient number of armed men, the effective strength of the garrison would slightly exceed four hundred. The enemy, at a rough estimate, outnumbered them by three to one, and were on the whole better armed; the rifles and ammunition captured on the launch were sufficient to arm about a third of Rejeb's force. The food supplies might with care last for a week or two. Plenty of drinking water was to be got from an old well which the Arabs had cleared out at their first occupation of the island. The weakness of the defence was that a wide front--for it was not merely a question of holding the end of the causeway--had to be held by relatively small numbers. The channel between the island and the Turkish position was too deep to wade; but it was obvious that an enterprising enemy with a large preponderance of numbers would not find it an insuperable obstacle, and with half the causeway in their possession they could harass the defenders until an attack in overwhelming force was possible. Burnet saw that his first concern must be to prevent the enemy from pushing farther along the causeway. That should be practicable. It was more doubtful whether he would be able to dislodge them from the position they had already gained. The sudden outburst of fire from the Turks on the previous evening had soon died down when they found that the Arabs made no attack, and so far the morning had been quiet. Taking advantage of their inactivity, Burnet went cautiously to the end of the causeway, examined the breastwork which the Arabs had constructed with material from the ruins, and cast about for an emplacement for one of his machine-guns. His first idea was to instal it in a sort of blockhouse in the middle of the breastwork, from which it could sweep the causeway from end to end. But there was always a chance that the Turks would ultimately bring up field artillery; the blockhouse would then be their first objective, and the gun would very likely be put out of action. The second gun, which he intended to keep in reserve, might suffer the same fate. What then could be done?