"I'm going to guess it at once," he said. "Reginald Henson has been here."
"You are certainly a wonderful fellow," Heritage said, admiringly. "Nobody else could possibly have guessed that. He came to see me, of course."
"Oh, of course," Bell said, drily. "Naturally, he would have no ulterior motive. Did he happen to know that we had a kind of patient under the roof?"
Heritage explained that Henson seemed to know something about it. Also, by singular coincidence, he had met Van Sneck abroad. He expressed a desire to see the patient, but Heritage's professional caution had got the better of his friendship for once. Henson had given way finally, saying that he hoped to call again later in the day.
"It's a good thing you were firm," Bell said, grimly. "Otherwise there would have been no need for an operation on Van Sneck. My dear Heritage, it's quite time your eyes were opened to the true nature of your friend. Henson watched Steel and myself out of the house He wanted to see Van Sneck; he has probably known from the first that the latter was here."
"Matter of philanthropy, perhaps," Heritage suggested.
"A matter of murder," Bell said, sternly. "My dear fellow, Van Sneck was nearly done to death in yonder conservatory, and his would-be assassin was Reginald Henson."
"I was never more astounded in my life," gasped Heritage. "I have always looked upon Henson as the soul of honour and integrity. And he has always been so kind to me."
"For his own purposes, no doubt. You say that he found you a home after your misfortunes came upon you. He came to see you frequently. And yet he always harped upon that wretched hallucination of yours. Why? Because you were the Carfax family doctor for a time, and at any moment you might have given valuable information concerning the suicide of Claire Carfax. Tell Heritage the story of Prince Rupert's ring, Steel."
David proceeded to do so at some length. Heritage appeared to be deeply interested. And gradually many long-forgotten things came back to him.