"This man's face," I continued, "would be turned toward the shutter, his back to his comrade. Into this comrade's mind darts, like a lightning flash, the idea of committing the robbery alone, and so becoming the sole possessor of the treasure."
"Good, sir, good," said the landlord, rubbing his hands.
"No sooner conceived than executed. Out comes his knife, or perhaps he has it ready in his hand, opened."
"Why opened, sir? Would it not be a fixed blade?"
"No; such men carry clasp-knives. They are safest, and never attract notice."
"You miss nothing, sir," said the landlord admiringly. "What a magistrate you would have made!"
"He plunges it into his fellow-scoundrel's back, who falls dead, with the gimlet in his hand. The murder is explained."
The landlord nodded excitedly, and continued to rub his hands; then suddenly stood quite still, with an incredulous expression on his face.
"But the robbery is not committed," he exclaimed; "the house is not broken into, and the scoundrel gets nothing for his pains."
With superior wisdom I laid a patronising hand upon his shoulder.