I hastened to assure him I had certainly not got it out of any other person's head; but he smiled incredulously. "Probably," he suggested, "Mr. Elmsdale left some such sketch behind him--something, at all events, which suggested the idea to you." "If he did, I never saw nor heard of it," I answered. "You may have forgotten the circumstance," he persisted; "but I feel confident you must have seen something like this before. Perhaps amongst the papers in Mr. Craven's office." "May I inquire why you have formed such an opinion?" I said, a little stiffly. "Simply because this tri-sided square was a favourite project of the late owner of River Hall," he replied. "After the death of his wife, the place grew distasteful to him, and I have often heard him say he would convert the ground into one of the handsomest squares in the neighbourhood of London. All he wanted was a piece of additional land lying to the west, which piece is, I believe, now to be had at a price--" I sat like one stricken dumb. By no mental process, for which I could ever account, had that idea been evolved. It sprang into life at a bound. It came to me in my sleep, and I wakened at once with the whole plan clear and distinct before my mind's eye, as it now lay clear and distinct before Mr. Harringford. "It is very extraordinary," I managed at last to stammer out; "for I can honestly say I never heard even a suggestion of Mr. Elmsdale's design; indeed, I did not know he had ever thought of building upon the ground." "Such was the fact, however," replied my visitor. "He was a speculative man in many ways. Yes, very speculative, and full of plans and projects. However, Mr. Patterson," he proceeded, "all this only proves the truth of the old remark, that 'great wits and little wits sometimes jump together.'" There was a ring of sarcasm in his voice, as in his words, but I did not give much heed to it. The design, then, was not mine. It had come to me in sleep, it had been forced upon me, it had been explained to me in a word, and as I asked myself, By whom? I was unable to repress a shudder. "You are not well, I fear," said Mr. Harringford; "this place seems to have affected your health. Surely you have acted imprudently in risking so much to gain so little." "I do not agree with you," I replied. "However, time will show whether I have been right or wrong in coming here. I have learned many things of which I was previously in ignorance, and I think I hold a clue in my hands which, properly followed, may lead me to the hidden mystery of River Hall." "Indeed!" he exclaimed. "May I ask the nature of that clue?" "It would be premature for me to say more than this, that I am inclined to doubt whether Mr. Elmsdale committed suicide." "Do you think his death was the result of accident, then?" he inquired, his face blanching to a ghastly whiteness.