But just here was a snag. Could so able a man as Roper have bungled so hideously as to have allowed himself and his wife to be caught in the trap he had arranged for Averill? Or had he intended to murder Mrs. Roper also? There was certainly no evidence for suspecting this. But whether or not, what terrible Nemesis could have overtaken Roper? Had he really been drunk and paid for his indulgence with his life? French did not think so. He could not devise any convincing explanation of Roper’s death, and he began to wonder if this objection were not so overwhelming as to upset the theory of the man’s guilt which he had been so laboriously building up. He gazed out over the wide expanse of the moor with unseeing eyes as he dreamily puffed at his pipe and wrestled with the problem. And then a further point occurred to him. Did not this theory of the guilt of Roper throw some light on Ruth Averill’s visit to York? French had noted it as a curious coincidence that she should have left the house on the day before the tragedy. But now he wondered if it was a coincidence. Had her absence been arranged; arranged by Roper? He reconsidered the facts from this new angle. First, it was significant that all the arrangements had been carried through by Roper. Just as in Whymper’s case, Mr. Averill was supposed to be the prime mover, but his power was manifested only through Roper. Roper it was who handed Ruth the note from Mrs. Palmer-Gore; doubtless a forged note. Roper had produced the ten pounds. Roper had arranged about the journey, and Roper had used his influence to prevent Ruth from seeing her uncle. When she had persisted she found the old man asleep, breathing heavily and looking queer and unlike himself. As to the cause of that appearance and that sleep French could now make a pretty shrewd guess. Roper had been faced with a difficulty. He could not keep Ruth from her uncle without arousing suspicion. Nor could he allow her to have a discussion with him or his plot would have been exposed. He had, therefore, taken the only way out. He had drugged the old man. Ruth could pay her visit, but she would learn nothing from it. French was thrilled by his theory. It was working out so well. He was congratulating himself that at last he was on the right track, when another snag occurred to him and brought him up, as it were, all standing. The Palmer-Gore invitation could not have been forged! Had Mrs. Palmer-Gore not written it, the fact would have come out on Ruth’s arrival at York. Here was a rather staggering objection. But the more French thought over the case as a whole, the more disposed he became to believe in Roper’s guilt. The man was a clever scoundrel. Perhaps he had been able to devise some way to meet this difficulty also. On the whole French was so much impressed by his theory that he determined to go into it without loss of time in the hope that further research would lead to a definite conclusion.