"It may have been your grandmother! Let's get into the place and have a look round. The window's too high to climb; is the door open?"
"There's no door."
"So much the better. Come on."
They hastened to the front, and through the doorway into the hall. The house was silent as a tomb. On either side opened a doorless room. They entered the one on the right--that in which Pratt had believed he saw a moving figure. It was pervaded by a subdued greenish sunlight, becoming misty by reason of the dust their footsteps had stirred up. It held neither person nor thing. They crossed to the opposite room, which, being out of the sunshine, was in deep gloom. This, too, was empty. Passing the staircase they arrived at the back premises, a stone-flagged kitchen and scullery. Both were bare; even the grate had been removed.
"Now for upstairs," said Pratt. "They've made a clean sweep down here."
They mounted the staircase, at first treading carefully, then with confident steps as they found that the creaking stairs were sound. There were four rooms on the upper storey, two of them exposed to the sky. Of these the floors were thick with blown leaves, twigs, birds' feathers, fragments of tiles and bricks, broken rafters, and the debris of the ceiling. The other two, roofed and whole, were as bare as the rooms below. Through the empty casement of one they caught sight of the tower in the grounds of Mr. Ambrose Pratt's house, and the upper windows and roof of the house itself. Pratt's appreciative eye was instantly seized by the prospect--the foreground of low thicket; the glistening stream; the noble trees beyond, springing out of a waving sea of sun-dappled bracken; the gentle slope on whose summit stood the buildings, and in the far background the rolling expanse of purple moorland. For the moment he forgot the shadowy figure he had seen, and lingered as if unwilling to miss one detail of the enchanting landscape.
"There's no one here," said Armstrong, matter-of-fact as ever.
"I dare say it was an illusion. Look how the sunlight catches the ripples, Jack. And did you see that kingfisher flash between the banks?"
"I'll go and have another look downstairs," Armstrong responded. "I'll give you a call if I find anything."
He felt, as he went down, that perhaps he would have done better to be candid with Pratt. Why make any bones about an incident capable, no doubt, of a simple explanation? The tramp, if tramp he was, had, of course, the objection of his kind to being found on enclosed premises, even though they were a ruin. Yet it was strange that he had left no tracks--had he not? Armstrong was suddenly aware of something that had hitherto escaped him. There was no dust, no litter on the stairs. Singular phenomenon in a long-deserted house! And surely the floor of the room in which Pratt now stood, unlike the other floors, was clear. It, and the staircase, must have been swept. Why? Not for tidiness--no tramp would bother about that. For what, then? Secrecy? Dusty floors would leave tell-tale marks--and with the thought Armstrong hurried down to the room in which the figure had been seen, and examined the floor. Yes! besides the footprints of himself and Pratt between door and window, there were others along the wall at the back of the room. The fellow must have slipped out with the speed of a hare. Armstrong perceived at once the clumsiness of the attempt at secrecy, for the very fact that some of the floors were swept gave the game away. At the same time, he was puzzled to account for the man's motive. The island was deserted; it was no longer the scene of picnics; the villagers avoided it; why then should a casual visitor--for there was no evidence of continuous occupation--be at the pains even to try to cover up his movements? The strange oppression of the previous night returned upon Armstrong's mind, and he roamed about the lower floor in a mood of curious expectancy.