"Ah!" said Devlin. "Mr. Kenneth Dowsett."

A light seemed to dawn suddenly upon me, but the suggestion conveyed in Devlin's significant tone so amazed me that I could not receive it unquestioningly.

"Do you mean to tell me," I cried, "that you suspect Mr. Dowsett of complicity in this frightful murder?"

"I mean to tell you nothing of my suspicions," replied Devlin. "It is for you, not for me, to suspect. It is for you, not for me, to draw conclusions. What I know positively of Mr. Dowsett--with whose name I was unacquainted until last evening, when you mentioned it in Lemon's house--I will tell you, if you wish."

"Tell me, then."

"It is short but pregnant. Through Mr. Kenneth Dowsett's mind, as I shaved him and dressed his hair on Friday last, passed the picture of a beautiful girl, with golden hair, wearing a bunch of white daisies in her belt. Through his mind passed a picture of a lake of still water in Victoria Park. Through his mind passed a vision of blood."

"Are you a devil," I exclaimed, "that you did not step in to prevent the deed?"

"My dear sir," he said, seizing my arm, which I had involuntarily raised, and holding it as in a vice, "you are unreasonable. I have never in my life been in Victoria Park, which, I believe, covers a large space of ground. Why should I elect to pass an intensely uncomfortable night, wandering about paths in an unknown place, to interfere in I know not what? Even were I an interested party, it would be an act of folly, for such a proceeding would lay me open to suspicion. A nice task you would allot to me when you tacitly declare that it should be my mission to prevent the commission of human crime! Then how was I to gauge the precise value of Mr. Dowsett's thoughts? He might be a dramatist, inventing a sensational plot for a popular theatre; he might be an author of exciting fiction. Give over your absurdities, and school yourself into calmer methods. Unless you do so, you will have small chance of unravelling this mystery. And consider, my dear sir," he added, making me a mocking bow, "if I am a devil, how honoured you should be that I accept you as my comrade!"

The tone in which he spoke was calm and measured; indeed, it had not escaped my observation that, whether he was inclined to be malignant or agreeable, insinuating or threatening, he never raised his voice above a certain pitch. I inwardly acknowledged the wisdom of his counsel that I should keep my passion in control, and I resolved from that moment to follow it.

"You locked the shop-door," I said, "when Mr. Dowsett left you just now."