"If he has," said Amberley in a very level voice, "if he has, he won't trouble the hangman."
This sinister pronouncement, coupled with the look on Amberley's face, led the sergeant to infer that he had discovered something interesting, though not of much value as a clue. Feeling that the occasion was one for a display of tact he made no comment on his discovery, but merely requested Mr. Amberley to go easy. "No use meeting trouble halfway, sir," he said. "If you was to go and do a murder, where'd I be?"
Amberley gave a mirthless laugh. "Making a sensational arrest, I expect."
"I'd be in a very awkward position, that's where I'd be," replied the sergeant. "If I thought you meant it I'd be obliged to take away that gun you've got sticking into my hip at this very moment."
"I'm more likely to choke the life out of the swine," Amberley said. "I don't think he's done it yet. I'm pinning my faith to that - keep a lookout for a constable. Another killing would be fatal to him. Mark Brown's death passed for an accident, but another accident would be suspicious, to say the least of it. Shirley is to disappear. No body, no conviction, Sergeant."
"I get you, sir. Taking her for a ride and bumping her off miles from Upper Nettlefold?"
"Not unless he's a fool. If he does that, and the body's found, it will be traced back to him. Miss Brown doesn't own a car. How did she get so far afield? Any jury would assume that she had been taken there by her murderer. Much too dangerous. The body must be disposed of. Put yourself in the murderer's place, Sergeant. How is that to be done?" Various gruesome visions came before the sergeant's eyes, but he thought it wiser not to advance a suggestion. A gentleman who had fallen in love with a young lady wouldn't take kindly to the thought of dismembered corpses or charred fragments. "We don't want to start talking horrors, sir," he said severely.
"I see," said Amberley. "Quicklime. No. No."
"Of course not, sir. Whoever heard of such a thing:"
"You're wrong," Amberley said. "I know you're wrong. He's heading south. The sea, Sergeant, the sea!"