“I suppose twins always are alike,” said George. “But if it ever came to a question of identification, there would be one way of distinguishing us. Do you know George well, Mr. Pepper?”

“He’s a dear old pal of mine.”

“You’ve been swimming with him perhaps?”

“Every day last August.”

“Well, then, you would have noticed it if he had had a mole like this on the back of his neck, wouldn’t you?” He turned his back and stooped and showed the mole. His collar hid it at ordinary times. I had seen it often when we were bathing together.

“Has George a mole like that?” he asked.

“No,” I said. “Oh, no.”

“You would have noticed it if he had?”

“Yes,” I said. “Oh, yes.”

“I’m glad of that,” said George. “It would be a nuisance not to be able to prove one’s own identity.”