Foe a while Dora Harrington and Lionel Crawford were silent, he still with the look of an enraptured visionary on his face, she perplexed, wondering, disturbed. What could this secret be which he, the man to whom she was engaged, never told her? One thing appeared plain to her, it was not a secret in which Dominique was directly concerned. It was the old man's secret, communicated by him to her lover. Yet it was not pleasant to think that Dominique, who seemed so candid, so outspoken, so open, should have something which he had concealed from her. The notion of a secret was cold and dire. He had one: he might have many, as he had never even told her that he owned this queer tower, standing all alone in those dark, forbidding ways by the river. Of late Dominique had not written to her as often or as affectionately as of old. True, he was not in good spirits about his worldly prospects. She had told him over and over again, when he asked her, that she would marry him on anything or nothing. Who or what was this old man, that he should be mixed up with Dominique's affairs long ago; that he should have stood between her and the Thames to-night? Was it possible this old man would tell her nothing more? He had excited in her curiosity, vague fears. Would he do nothing to allay either? Thus to be saved from the fate she intended for herself that night, to find in her protector a friend of his, and then to be confronted with a mystery in which Dominique had a part, were, surely, enough things to make this night ever memorable. "Mr. Crawford," said the girl, "I can never forget the service and the kindness you have done me. Will you not do me an additional favour by telling me something of this secret which affects him?" The girl had finished the tea and eaten some bread by this time. "Take off your hat," he said. "Lean back and rest yourself, and I will tell you something more. "Ten years ago I was as lonely a man as I am now. All my family had drifted away from me. Most of them were dead. Some of them had married, I know not whom. My studies always occupied me, and after the death of my wife, whom I tenderly loved, I went deeper than ever into my books. "Most of my children left me when they were young, and went abroad. I had six children in all. From time to time one left me until all were gone, and ten years ago I had no more clue to the whereabouts of any than I have to-day, except that I knew some were in the grave. "I was then better off than I am now; but I have still enough to live on, and to buy a book now and then. My books are all above. All my interest lies in one direction, all my books treat of the same subject--the history of the past, the history of the men and women and places of old times. My interest in the present closed with the death of my wife. But, somehow or other, since the time of which I speak, ten years ago, I think I have grown less exclusively devoted to my favourite pursuit than I was at the time of the dispersion of my family. "I do not often speak to anyone except to those of whom I want to buy; but I cannot help thinking there is a link between you and me, for are you not betrothed to him who owns this tower, and has not this tower for ten years been the chief object of my attention, of my solicitude? Was it not to him I first told the secret which I had carried with me eight years? Is he not now the only person who knows my secret, and when the time comes for divulging that secret to a few, are not you to be the first to hear it? "Well, ten years ago I was, as I have said, as much alone in the world as now. I had always a notion that something was to be discovered in connection with this Porter Street. Here and there in my books there were vague hints, misty statements, that in this street had taken place something of the greatest importance, something which might in the greatest degree excite the interest of an archaeologist. But you see, the street is long, a mile long, I dare say, and to search every inch of a street a mile long would be altogether out of the question. "At that time I was living close by. There were certain old book-shops, between Longacre and the Strand, which I visited almost daily. Here, one evening, I picked up a battered old volume for a few pence. It was dated 1625. It turned out to be of no great interest; but on bringing it home, I was struck by two facts--first, that the book, although battered, was complete; and, second, it contained some memoranda in manuscript, one bearing these startling words: 'A great fire has broken out, and is spreading towards us. There is not a minute to be lost. What can be removed is to be removed to Kensington. What cannot be removed is to be left where it now is.' "This memorandum was dated: 'Daybreak, 3rd September, 1666.' "It was, of course, in the spelling of the period. Underneath this memorandum appeared the words and figures: 'Speght's Chaucer, page 17, lines 17 to 27.' "I have told you already that I had something like a hint of what I wished to find out. I am not free to tell you why the first of these memoranda interested me profoundly, and shone before me like a revelation. I seemed to be on the point of a great discovery, a discovery of the utmost importance to me, a discovery which had fascinated my imagination for years. "I am free to tell you why the second memorandum filled me with despair. It was essential that the book referred to in memorandum number two should be found. The clue in my possession was absolutely of no value without a copy of Chaucer. Before giving way to despair, I had looked over the passage in the reference. I had read over twenty lines above and below without being able to find the slightest hint to a clue. It was evident from this fact that the text of the poet threw no light on the subject, and that the intention of the man who had written the memorandum was that reference should be made, not only to the particular edition specified, but to an individual copy of that edition. "My despair was all the greater because I seemed to be half-way towards success. I could not rest indoors. I wandered forth into the streets without any definite object in view. To the average student of history, the discovery of this volume containing a reference to the Great Fire, written at the very moment it was raging, would have been inestimable; but to one who was in quest of a particular object, and had come within a measurable distance of it, without being able to touch it, this book was a curse. "Before I knew where I was I found myself standing in front of the identical shop where I had bought the volume. I went listlessly over all the other books exposed for sale in front of the window. I saw nothing corresponding to the object of my search. "Then suddenly a thought struck me. The book I had bought was valueless. A copy of this particular edition of Chaucer would fetch money. I went inside, and asked the man if he had any other books belonging to the lot among which the one I had purchased was. "He told me he had several; that he bought the lot in an old, tumble-down house in Wych Street, where the books had lain for ever so long, and that they were reputed to be salvage from the Great Fire. "Imagine my excitement, my delight, when I found a copy of Speght's edition, and upon opening the volume, and referring to the passage indicated, I discovered writing on the margin. This writing was briefer than that in the former volume. It was simply: 'St. Prisca's Tower. See Mentor on Hawking, 1625.' This was the book I had bought a short time previously. The chain was now complete. The area of inquiry was absolutely limited to the ground upon which this tower now stands. In the Great Fire of Charles's reign the church and tower of St. Prisca had been attacked by the flames, and the church had been completely destroyed. The lower portion of the tower, however, was found by Wren to be sufficiently good for the purposes of rebuilding, and so, about ten feet above the ground of these walls belong to the old tower. Later on the modern church was pulled down; but for some reason, I cannot find out, the tower has never been interfered with since. "These books had evidently been carried away from the region of the fire to the fields where Kensington now stands; and then, when the fire was subdued, carried back to Wych Street, where they had remained until the bookseller who sold them to me had bought them about ten years ago." Here the old man finished his narrative, which had been delivered in a monotonous tone. His eyes were fixed, staring intently before him, and he seemed to be wholly oblivious of the fact that Dora was listening to him. He was not, however, unmindful of her presence; for no sooner had he concluded, than he looked at her directly and said: "I have told you all I can; all I may. Dominique Lavirotte and I are the only persons who know the rest, and you know more than anyone else in the world except him and me. You must be tired now. I never told this story before, and, in all likelihood, I never shall again." It was now close to two o'clock in the morning. To the opening words of the old man Dora had given little attention. In fact the events of that night, until she had begun to feel refreshed by the rest and tea, had left a very weak impression on her mind, and she would have found it hard to say whether the occurrences had been real or figments of her brain. As the story advanced, she had felt a more lively interest in it, and towards the end she found that she was listening with awakened curiosity. The old man said: "I will bring you down a rug, and then you must try and get a little sleep. I shall have to work a couple of hours yet in this welcome rain." He brought the rug and spread it over her, and then emerged once more upon the roof.