XVI

Williams thought highly of his idea. It had come to him that morning while thinking of the person he had heard descending the stairs, the person he insisted was Mrs. Stokes. In its inception it had been directed chiefly at that lady, but now with the mystery complicated by the intrusion of a new figure its usefulness would be extended. The thing that was aimed at Mrs. Stokes, would include Joe Tracy. That was how he put it to Rawson to gain the consent and cooperation of his superior. For he had little interest in Joe Tracy himself, inclining to agree with Bassett and Anne that the boy had nothing to do with the murder and was not on the island.

It was a simple and practicable plan—a watch kept for the rest of the night on the stairs and certain points of exit. In the face of positive orders two people had come from the upper floor the night before, Miss Tracy on an errand that Rawson thought suspicious, Mrs. Stokes, in Williams’ opinion, to communicate with her husband. Even if both men were wrong some powerful incentive was making them take such risks and it was natural to suppose that incentive might be strengthened after twenty-four hours of strain and uncertainty. They might try it again, and to catch them at it, surprise them in the act—if they didn’t break down on the spot—a little grilling would do the job.

As for the boy—if he was still in the top story as Rawson thought, he’d certainly not stay there after they’d been searching the place for him. He’d know they were on his trail, that his only hope was getting away and the night was dark enough to tempt him. If he was outside he’d discover his escape was cut off and what would he want then—food? He’d see himself faced by starvation and the place he’d make for would be the kitchen.

Rawson looked at his assistant with an approving eye. The idea was good, excellent, and without waste of time they arranged the distribution of the watch.

Williams would take the front stairs, his particular prey was there and he had already located the position of the electric-light button. Rawson would station himself in the kitchen with its two doors one to the outside, one to the hall. As Williams had pointed out it was the place to which Joe, escape blocked, would inevitably turn. The living-room they would assign to Shine, less important than either of the other ambushes, but commanding the entrance to the side wing and the path to the causeway and dock. Any one descending the back stairs to make an exit from the house would either turn to the kitchen or go through the living-room, and whichever way they took, would run into a trap. The men were satisfied, each one was detailed to the spot where he might expect to apprehend the object of his suspicion. The living-room, central and exposed, might safely be left to Shine.

They found Shine in the butler’s room sleeping soundly on the outside of the bed. He was acquainted with the plan, and stumbling and heavy-eyed followed them. In the hall Rawson left them, taking his way to his hiding-place, the other two faring on to the scene of Shine’s duties. Here he received his instructions, special emphasis being laid on the door that led to the kitchen wing and the back stairs. Shine looked from the door to Williams with a perplexed frown. He did not like to admit—no more than he had liked to display the healthy vigor of his appetite—that he was so sleepy it was doubtful whether he could keep awake. In this embarrassing position, when he desired to acquit himself creditably and feared the weakness of his flesh, he too had an idea. He did not know if it would be acceptable and broached it with a cautious preamble.

They just wanted to know who the person was, didn’t they? He wouldn’t have to catch them, which would be nearly impossible in the dark and was unnecessary as no one could get off the island. To see them, be able to identify them, get on to who was stealing round the house, was the point. If that was enough he’d a way of doing it, the surest and most efficacious way it could be done, no scrambling round the furniture, no uncertainty—he’d set his small camera for a flashlight photograph. The materials were all at hand, he’d gathered them together for a flashlight picture of the company. All he had to do was to get them ready and if any one entered by the door he was to watch, he’d have their number before they knew it.

Williams was interested—it was a neat trick and tickled his fancy. As he was ignorant of the process, Shine explained it, getting his properties from the cabinet as he spoke. The flashlight powder in a saucer on the table, then a double wire extending from it to a point above the door—the pair of antlers would answer. There the wire would be cut, one-half hanging down from the antlers, the other twisted round the door handle, its end standing out. When the door was opened the two severed ends would come in contact and make the circuit which would set off the powder. He did not tell Williams that the taking of the picture could be achieved whether he was asleep or awake, but that the camera would make its record whatever his state was an immense relief to his mind.

Williams left and he quickly completed his preparations. The antlers served his purpose well, the depending cord was in exactly the right position and before he made his final adjustment of the two wires he unloosed the latch of the door that it might open easily and noiselessly at the first push of a stealthy hand. Then, his camera in place, he turned off the lights. The room was suddenly plunged into Egyptian blackness; he had to feel for the chair he had pulled up and grasping the tripod, nearly upset it. Swearing under his breath he found the arms of the chair and let himself down upon it carefully, to avoid creaking. The silence of the house closed round him, a silence that was like oblivion. The darkness showed no break as his glance traveled over it. A solid impenetrable wall, it was hard to look at, the eye required something to rest upon. After he had stared into it for what seemed a measureless stretch of time, he felt he must shut his eyes for a moment of respite. He did so, his head drooped, nodded, sunk, and he lay a big crumpled figure held in the embrace of the chair.