"He discovers that he has not got the real Prince Rupert's ring."
Rawlins looked up with a slightly puzzled air.
"Will you kindly tell me what you mean?" he said.
"It was a forgery. Van Sneck made a copy from a mere description. That copy served its purpose with a vengeance, and is now at the bottom of the North Sea. I need not go into details, because it is a family secret, and does not concern our conversation at all. At that time the real ring came into Henson's possession, and he wanted a copy to hold over the head of an unfortunate lady whom he would have ruined before long. You told me just now that Van Sneck had fallen in love with Prince Rupert's ring and could hardly bear to part with it. He didn't."
"No? But how could he retain it?"
"Quite easily. The copy was quite faithful, but still it was a copy. But secretly Van Sneck makes a copy that would deceive everybody but an expert, and this he hands over to—"
"To Henson as the real ring," Rawlins cried, excitedly.
Chris smiled, a little pleased at her acumen.
"Precisely," she said. "I see that you are inclined to be of my opinion."
"Well, upon my word, I am," Rawlins confessed. "But I don't quite see why—"