By the light of a match he saw that the flagstone was slightly depressed. Then he caught sight of Warrender's electric torch lying on the ground, and was seized with a vague uneasiness. He picked up the torch. Revolving the stone, he heard something slide with a metallic rattle along its surface, and felt a smart blow on one of his feet. He flashed the torch, and saw a hammer and a chisel. Still more uneasy, he clambered up into the cellar, and without lowering the flagstone, climbed on to the staircase.
"You there, Phil?" he called up.
There was no answer. The door at the top was open. He rushed up, ran through the kitchen and the corridor to the front of the cottage, and looked anxiously around. No one was in view.
"What on earth is he doing?" he thought.
It was clear that Warrender had fetched the tools from the motor-boat and returned to the cellar. Why then had he left them there? Where had he gone? What could have interrupted him?
Pratt felt himself on the horns of a painful dilemma. He had now the instruments of his uncle's deliverance; one impulse urged him to hurry with them back to the tower. On the other hand, Warrender's disappearance argued that something untoward had happened, and he was loth to leave the spot without making an attempt to find him. For a few moments he stood in the doorway, weighing the one course against the other. A search for Warrender might prove fruitless, and in any case would take time. Meanwhile affairs at the tower might be developing in a way that would nullify the prime motive that had actuated them all--the release of his uncle. It seemed that this had a paramount claim upon him, and he turned, reluctantly, to retrace his steps to the cellar.
As he passed the foot of the staircase to the upper floor, it occurred to him that from the windows there, giving a wider outlook over the surroundings of the cottage, he might see Warrender approaching: perhaps, indeed, as the result of an after-thought, he had made a second visit to the motor-boat. Pratt ran upstairs, and going from room to room, threw a searching glance upon the prospect. Neither on the eastern side nor on the western was there anything to attract his attention. But looking out of the window of the room facing south, he noticed that the foliage of the thicket beyond the weedy path was violently disturbed. Some one was moving in it, towards the ruins. He watched eagerly: surely it was Warrender returning. Presently two legs came into view; but they were not Warrender's. They were encased in rusty brown leggings. In another moment the figure of Rush emerged from the thicket upon the path, and immediately behind him was a second form, that of a tall and heavily built man with a broad flattish face. When free from the thicket they quickened their pace.
Pratt hesitated no longer. The men were evidently making for the ruins: perhaps they intended to proceed along the tunnel. It was imperative that he should anticipate them. He hastened downstairs, and had just reached the cellar when he heard clumping footsteps overhead. Leaping into the cavity, he swung the stone over, turned the hand-grips, and by the light of the torch bolted along the tunnel. After running about twenty yards he switched off the light and stopped. Voices came from behind him; then he heard two heavy thuds in succession; the men had jumped into the tunnel. The flagstone banged as it was swung carelessly into place; the men were coming after him. Without more delay he set forward with all speed, guiding himself by touching the walls with his outstretched hands.
CHAPTER XXI
TRAPPED