When Bent had gone away to the town, Brereton lighted a cigar, stretched himself in an easy chair in front of a warm fire in his host's smoking-room, and tried to think clearly. He had said to Bent all that was in his mind about Harborough and about Miss Pett—but he had said nothing, had been determined to say nothing, about a curious thought, an unformed, vague suspicion which was there. It was that as yet formless suspicion which occupied all his mental powers now—he put Harborough and Miss Pett clean away from him.

And as he sat there, he asked himself first of all—why had this curious doubt about two apparently highly-respectable men of this little, out-of-the-world town come into his mind? He traced it back to its first source—Cotherstone. Brereton was a close observer of men; it was his natural instinct to observe, and he was always giving it a further training and development. He had felt certain as he sat at supper with him, the night before, that Cotherstone had something in his thoughts which was not of his guests, his daughter, or himself. His whole behaviour suggested pre-occupation, occasional absent-mindedness: once or twice he obviously did not hear the remarks which were addressed to him. He had certainly betrayed some curious sort of confusion when Kitely's name was mentioned. And he had manifested great astonishment, been much upset, when Garthwaite came in with the news of Kitely's death.

Now here came in what Brereton felt to be the all-important, the critical point of this, his first attempt to think things out. He was not at all sure that Cotherstone's astonishment on hearing Garthwaite's announcement was not feigned, was not a piece of pure acting. Why? He smiled cynically as he answered his own question. The answer was—Because when Cotherstone, Garthwaite, Bent, and Brereton set out from Cotherstone's house to look at the dead man's body, Cotherstone led the way straight to it.

How did Cotherstone know exactly where, in that half-mile of wooded hill-side, the murder had been committed of which he had only heard five minutes before? Yet, he led them all to within a few yards of the dead man, until he suddenly checked himself, thrust the lantern into Garthwaite's hands and said that of course he didn't know where the body was! Now might not that really mean, when fully analyzed, that even if Cotherstone did not kill Kitely himself during the full hour in which he was absent from his house he knew that Kitely had been killed, and where—and possibly by whom?

Anyway, here were certain facts—and they had to be reckoned with. Kitely was murdered about a quarter-past nine o'clock. Cotherstone was out of his house from ten minutes to nine o'clock until five minutes to ten. He was clearly excited when he returned: he was more excited when he went with the rest of them up the wood. Was it not probable that under the stress of that excitement he forgot his presence of mind, and mechanically went straight to the all-important spot?

So much for that. But there was something more. Mallalieu was Cotherstone's partner. Mallalieu went to Northrop's house to play cards at ten o'clock. It might be well to find out, quietly, what Mallalieu was doing with himself up to ten o'clock. But the main thing was—what was Cotherstone doing during that hour of absence? And—had Cotherstone any reason—of his own, or shared with his partner—for wishing to get rid of Kitely?

Brereton sat thinking all these things over until he had finished his cigar; he then left Bent's house and strolled up into the woods of the Shawl. He wanted to have a quiet look round the scene of the murder. He had not been up there since the previous evening; it now occurred to him that it would be well to see how the place looked by daylight. There was no difficulty about finding the exact spot, even in those close coverts of fir and pine; a thin line of inquisitive sightseers was threading its way up the Shawl in front of him, each of its units agog to see the place where a fellow-being had been done to death.

But no one could get at the precise scene of the murder. The police had roped a portion of the coppice off from the rest, and two or three constables in uniform were acting as guards over this enclosed space, while a couple of men in plain clothes, whom Brereton by that time knew to be detectives from Norcaster, were inside it, evidently searching the ground with great care. Round and about the fenced-in portion stood townsfolk, young and old, talking, speculating, keenly alive to the goings-on, hoping that the searchers would find something just then, so that they themselves could carry some sensational news back to the town and their own comfortable tea-tables. Most of them had been in or outside the Court House that morning and recognized Brereton and made way for him as he advanced to the ropes. One of the detectives recognized him, too, and invited him to step inside.

"Found anything?" asked Brereton, who was secretly wondering why the police should be so foolish as to waste time in a search which was almost certain to be non-productive.

"No, sir—we've been chiefly making out for certain where the actual murder took place before the dead man was dragged behind that rock," answered the detective. "As far as we can reckon from the disturbance of these pine needles, the murderer must have sprung on Kitely from behind that clump of gorse—there where it's grown to such a height—and then dragged him here, away from that bit of a path. No—we've found nothing. But I suppose you've heard of the find at Harborough's cottage?"