By this time the reinforcements had come up stealthily from the rear. Rejeb threw them out on the wings, so that the defending force, its main strength in the centre, covered a rough semi-circle nearly half a mile in extent.
Within a very few minutes the enemy's intentions were disclosed. Advancing on a wide front, taking cover wherever it was possible, they came on in short rushes. It was seen now that the majority of them were Arabs, and the total force could hardly have been less than a thousand men. Rejeb ordered his men to fall back slowly, holding on as long as they could without the risk of being cut off, and inflicting as much loss as possible on the enemy whenever they crossed stretches of open ground.
It was clear to the chief, as to Burnet and Ellingford, that Major Burckhardt's profession of knowledge of the stronghold's position had not been vain. Clearly they had to look forward to a siege. They were not strong enough to defeat the enemy in the open, and as soon as the safety of the aeroplane was assured, they must retreat along the causeway and make the best use of their natural advantages.
For nearly two hours Rejeb's Arabs fell back steadily. More than once the enemy sought a decision by attempting to rush the defenders, now in the centre, now at one or other of the wings. At one moment it seemed that the left wing was in danger of being crushed, but Rejeb, who throughout the day showed many of the best qualities of generalship, sent a runner to the rear to bring up a portion of his mounted reserve, now less than half a mile away. In a few minutes a hundred superbly mounted warriors galloped to the threatened point, swept like a whirlwind upon the dismounted enemy, rode through them again and again, heedless of losses, and not only defeated the flanking movement, but caused a check in the whole line.
Then came word that the aeroplane had been conveyed across the causeway to the centre of the stronghold. From this moment the retreat became more rapid, though still as methodical as before. Late in the afternoon the Turks, who formed the right and right centre of the attacking force, and had fought more steadily and doggedly than their Arab allies, gained a position from which, though at extreme range, they began to command the end of the causeway. Rejeb drew nearly all his men together, posted them under cover, and concentrated his fire on the assailants on his left, in the hope of holding them off until darkness rendered it possible to slip away. At sunset, before the enemy knew what was happening, the chief withdrew his little force swiftly across the causeway. The day's work had cost him barely a score of casualties, while the enemy's losses were probably five or six times as great.
"That was a top-hole rearguard action," said Ellingford to Burnet as they went together to Rejeb's tower. "I'd no idea that Arabs could ever behave so steadily."
"It's due to their chief," replied Burnet. "He's got stuff in him, and he's going to be very useful. By George! I'm dead tired."