But when daylight came again he discovered that the enemy had had another purpose in their shelling. The bombardment continued. The scouts from their high posts above reported that they saw men's heads in the ground on the further side of the clearing. Unable to make out what they meant, Tom climbed the side of the nullah under cover of the bushes until he reached the trench, and cautiously looked out across the open space beyond the barricade. Some thirty yards in advance of the edge of the forest, on the level of the ground, he saw the heads of several askaris moving up and down. At one moment a dozen heads were in sight, the next some of them disappeared, only to bob up again a few seconds later.

"By George, they're digging," he said to himself.

Quite ignorant of all military operations except those simple manoeuvres learnt in the course of field days with his school cadet corps, he was at first at a loss to understand why the enemy were digging a trench which was apparently to extend from the forest to the nullah. He had perhaps heard the word sap, but it conveyed nothing to his mind. It was not long, however, before he guessed the meaning of this unlooked-for movement. The enemy were digging a means of approach by which they would avoid the inevitable losses of a rush across the open, and the bombardment during the night had been designed partly to cover the sounds of their tools.

Watching intently, he noticed that the direction of the enemy's trench was not a straight line towards the barricade, but a series of short zigzags, obviously to minimise the risk of interference by enfilading fire.

"I ought to try to stop that little game," he thought.

He lifted his rifle, and took a shot at one of the moving heads. Instantly they all sank down; whether he had hit he could not tell; and a fusillade burst from the trees on the other side of the clearing. For some minutes he saw no more of the diggers; then a head and shoulders showed for a moment, a little nearer than the nearest head had been before.

"I can't stop them, apparently," he thought, "but I can delay them."

Hurrying down to the trench behind the barricade, he sent a dozen of his best marksmen, including a couple of the askaris, to the position he had left, with orders to fire at the diggers whenever they appeared. At their first shots there was another fusillade from the forest; then an interval of about a quarter of an hour during which the enemy was silent, though Tom's men continued to snipe. After that the enemy, having located the position of the trench, began sniping in turn; but the men were so well hidden that they suffered no loss. Presently, however, a shell burst a few yards above the trench, scattering splinters upon its occupants; and a few minutes later another shell fell plump on the parapet at the northern end, killing two men and wounding several. Tom at once withdrew the snipers from their position, and sent them into the similar trench on the other side of the nullah. From this they sniped for a considerable time before they were again detected, and when shells began to fall there also, Tom removed the men to comparative safety in the bed of the nullah. The wounds inflicted by the shells were so severe that he did not feel justified in exposing his willing soldiers to injuries which he was unable to deal with satisfactorily.

The sniping being thus put an end to, and a sortie being out of the question, Tom had to reconcile himself to the inevitable. The bombardment slowed down, either because the enemy were satisfied that it had crushed opposition, or maybe to save ammunition. Several times during the day Tom went up to his observation post, and noted the progress of the zigzags. The sap was so narrow that the enemy would have to advance in single file, and he thought his men behind the barricade would have an easy task in shooting them down when the attack came.

Next morning, however, he saw with something like dismay that the enemy had dug a trench across the clearing, parallel with the barricade, and about eighty yards from it. The full meaning of their work was now clear to him. They would reach the trench by means of their zigzag path. When the word was given, they would swarm out, and though their first wave must suffer from the defenders' fire, the distance they had to cover was so short, and they could be so safely reinforced, that they might overwhelm the defence by sheer weight of numbers. Some of the survivors of the first attack had come near enough to the barricade to see the moat, and no doubt, when the enemy attacked a second time, they would be prepared to meet that not very formidable obstacle.