Lawrence swept round to observe the effect of this bolt from the blue. A great troop of horses was galloping wildly along the nullah to the west. He caught sight of their forms, black, brown and grey, wherever there were breaks among the trees. Farther up the nullah, where the sides were less steep, the frantic animals were dashing across the country in all directions. Beneath, a few lay motionless on the ground. Loth as he was to destroy or maim the unoffending beasts, he felt that this was not an occasion for half measures: there was too much at stake. In their panic flight it was inevitable that many of the horses must dash themselves to pieces in the ravines and fissures with which the country was seamed. To prevent the rallying of the rest, he set off in pursuit. Sweeping the ground like a shepherd's dog after a flock of sheep, he flew backwards and forwards and from side to side at the heels of the terrified animals. No more bombs were necessary. The whirr of the propeller behind them drove them on at the same mad rush, and in a quarter of an hour there was not a living horse within several miles of the encampment.

On returning towards the tower, Lawrence was surprised to see that the groups of Afghans had disappeared from around it. But as he crossed the nullah there were bursts of smoke from among the trees and the undergrowth, and above the hum of the propeller he heard the characteristic whistle of bullets. Later he discovered that several holes had been drilled in the planes. The firing ceased as suddenly as it had begun. Crossing the nullah almost at right angles, the aeroplane was visible for only a few seconds to the men hidden in the bottom.

From an embrasure high up in the tower a white handkerchief was fluttering in the breeze. Lawrence wished that he had some means of communicating instantly with the Major; but the attack from which he had just escaped proved that he could not venture to alight, nor could he be of any further service to the little garrison until the nullah had been cleared. It was necessary to drive the men up the ravine in the same direction as he had already driven the horses. There might be more difficulty in this, for the enemy were completely concealed by the trees and undergrowth, so that he could not tell exactly where they were. The only plan that promised complete success was to fly some distance down the ravine, and then work up it, dropping bombs when he approached the spot where the firing had broken out.

In a few brief sentences he explained his purpose to Fazl. Making a wide sweep he came back to the nullah half a mile to the east; then, reducing speed to the minimum, but keeping at a good altitude, he followed the winding course of the gully. The enemy played into his hands. Another burst of smoke revealed their whereabouts. Fazl instantly dropped a bomb, and turning to watch the effect, cried out that a dense cloud of smoke and dust had arisen from the scene of the explosion. Lawrence wheeled round again, described a wide semicircle, passing immediately above the tower, and, regaining the nullah, repeated the manoeuvre.

This time Fazl reported that he saw men among the trees, running up the ravine. The enemy could scarcely have chosen a less secure shelter. The explosion of a bomb in so constricted a space must be many times more destructive than in the open. But Lawrence had no inclination towards needless slaughter. His object would be achieved if he drove the men away as he had driven the horses. Knowing that they were on the run, he dropped another bomb to speed their flight; then swept round again, and pursued the same tactics as had already proved so effectual. When the enemy reached the less wooded part of the nullah, he found it easy to hover about their rear, and, without the further use of bombs, to impel them to the most desperate exertions by the mere harrying pursuit of the aeroplane.

He was not content until he had driven them many miles up the nullah. Whenever they showed a disposition to break away into the open country to right or left, a swoop of the aeroplane in that direction was sufficient to send them scurrying back. In their haste and panic they did not halt to fire again, and Lawrence was at length satisfied that even if they should recover their nerve and courage, they were too far away to trouble the garrison of the tower for at least a couple of hours.

On nearing the tower, he saw that several figures had emerged from the door at the foot. He glided down to within a few yards of it, and shouted a greeting to Major Endicott, who waved his hand in response. Then he sought for a landing-place. The ground in the immediate vicinity was too broken to allow of a safe descent; but after circling round once or twice, he discovered a space sufficiently flat and open for his purpose about a quarter of a mile away. Alighting there, he left the aeroplane in Fazl's charge, and, feeling very shaky on his legs after the exhausting and nervous work of the past two hours, he walked back to meet the British officer.

CHAPTER THE NINETEENTH

STALKED

"Masterly cattle-driving," were Major Endicott's first words as Lawrence joined him.