"You mentioned the fact, did you not," the lady who called herself Miss Pinsent observed, "that it was raining heavily at the time? Perhaps they stayed under the bridge to shelter."
"That's something I never thought of," Mr. Greene admitted, "perhaps for the reason that they both of them seemed quite indifferent to the rain. The young man in the dark clothes hadn't even an umbrella. I must admit that I allowed my thoughts to travel in another direction. Professional instinct, you see. It was a fairly broad canal, and the water was nearly up to the towing-path. I'd lay a wager it was twelve or fifteen feet deep. Supposing those two men had met on that narrow path and quarrelled! Supposing—"
"Don't!"
Mr. Raymond Greene stopped short. He gazed in amazement at Elizabeth Dalstan, who had suddenly clutched his hand. There was something in her face which puzzled as well as startled him. She had been looking at her opposite neighbour but she turned back towards the narrator of this thrilling story as the monosyllable broke from her lips.
"Please stop," she begged. "You are too dramatic, Mr. Greene. You really frighten me."
"Frighten you?" he repeated. "My dear Miss Dalstan!"
"I suppose it is very absurd of me," she went on, smiling appealingly at him, "but your words were altogether too graphic. I can't bear to think of what might have taken place underneath that tunnel! You must remember that I saw it, too. Don't go on. Don't talk about it any more. I am going up-
