“I think I now can guess why Doctor Thorpe was killed, and also prove who killed him.”
“Rot! What theory have you now formed?”
“Madame Clayton telephoned to me, Margate, just before the fatal shot was fired. I heard her voice and the report of the weapon.”
“But she spoke only your name,” Margate impulsively cried. “I’m sure of that, and——”
“Stop!” Nick sternly interrupted. “You could not be sure of it, could not possibly know it—if you had not been there.”
Margate recoiled with a scowl.
“You see that you betray yourself, Margate, if that were necessary,” Nick quickly added. “But it is not, Margate, since I now can guess precisely what occurred and what caused the crime.”
“You can, eh?” Margate’s voice took on a husky harshness.
“Easily,” snapped Nick, more sharply. “Madame Clayton saw by chance that scar on your head, probably that very evening, and she suspected your identity. That must have been after her son and his wife left the house. Doctor Thorpe called only incidentally, presumably to see Clayton. Burdened with her terrible discovery, she confided your criminal career and her consequent fears to the physician, and he advised her to call me by telephone and confer with me. She attempted to do so, and you, returning home and approaching the open French window at the time, and apprehending that your present knavish game would be thwarted—you shot him to prevent his revealing what the woman had told him. You then overcame her, or she may have fainted, and you drugged her and threw her into the condition in which I found her, bent upon keeping her so till you could carry out your designs upon Clayton. You planted the evidence that I found, and you since have had the woman’s nurse in your employ. That, Margate, is how and why it was done. There is little need to add to these details, little to assert that they are true, and that——”
Nick broke off abruptly.