"That I cannot say. Unless," here Tait hesitated before uttering his opinion, "unless Denis Bantry is the guilty person." "But that is impossible; that is out of the question," said Claude decidedly. "He was devoted to my father, as you know. Why should he turn and kill him without a cause?" "Ah!" said Tait significantly; "what if he had a cause, and a very good one, to kill your father. Recall your mother's confession. She returned at three o'clock in the morning and found her husband alone with Mona, the sister of Denis. She accused Mona of being her husband's mistress, and the girl confessed her guilt, which your father evidently could not deny. Now what is more probable than that Denis, attracted by the high voices, should have followed your mother to the room. There he would hear the truth, probably while waiting at the door. What follows? With his impulsive Irish temperament he dashes in, hot to avenge the wrong done to his sister. The dagger dropped by your mother is at his feet; he picks it up and kills his master on the instant. Your mother, in a faint on the floor, knows nothing of what is going on, and brother and sister remove the body to the river, where they drop it in. Then Mona is sent away by Denis to hide her shame and evade awkward questions, while he remains." "But why should he remain?" interrupted Claude smartly. "Would it not have been wiser for him to fly?" "And so confess his guilt. No! He induces Jeringham to fly, with a threat of denouncing him as the murderer of Larcher. Jeringham is in such a dilemma that, seeing that all the evidence will be against him, he takes to flight. Thereupon Denis is able to save his mistress, and himself, by denying that Larcher came to the house on that night. Of course, this is all pure theory; still it is as circumstantial as the rest of the evidence we have in hand." But Claude was by no means inclined to agree with this last remark. "There are flaws in your argument," he said, after a few moments' reflection. "If Denis intended to deny that my father was in the house on that night, why should he induce Jeringham to fly?" "To make assurance doubly sure. No doubt he intended first to put the blame on Jeringham, but finding that Mrs. Larcher was likely to be accused, he made things safe for her by denying that his master returned on that evening. Only four people knew of the return; Mona, who fled, Mrs. Larcher, who held her tongue to save her neck; Denis, who swore falsely to serve his mistress; and Jeringham, who thought he might be accused of the crime." "But why wouldn't he have denounced Denis?"