"You are surprised," he said, "to see so large a room in so small a house. We are now in part of what are usually supposed to be my farm-buildings. There are three rooms here which I use for different purposes. I will show you the other two later on." The library was lighted by a skylight arranged in such a way, that from outside it would not be visible. My companion sat down on a comfortable couch, and beckoning me to another, said-- "I must ask you to promise me that you will reveal nothing of what I am now going to say, or anything which I may show you until you have my permission. I have a strong opinion that for some reason or other the time has not yet come when it would be advisable to make generally known many facts which I have discovered belonging to a power which is lying dormant in all men. The world, however, is progressing quickly, and the responsibility must rest with you at some future time, when I am gone, as to the wisdom of making known part or all of the knowledge which you will gather from me." Saying this, he got up, and going to one of the shelves in his book-case, took down a volume. "You may judge," he continued, "by the collection here, that at one time I was an ardent lover of books. Now they have little interest for me: but this volume will always have a special value, for it was from it that I first gained the knowledge which has influenced my whole life. "While travelling in France, and making, as was then my custom, a round of any old book-stalls that came in my way, I noticed a small shop which outwardly had little appearance of containing anything of interest to the bibliomaniac. In the window there were various ancient curiosities, but knowing that these antique dealers sometimes bought books which they did not display, it seemed worth while to make an inquiry. I was well rewarded, for the old man, after saying that he did not as a rule buy books, told me that he had at various times picked up at sales a few which he usually sent to be sold by auction in Paris. He had some by him at the time, and amongst these a curious Latin manuscript. Though evidently a seventeenth-century work, it was not dated. I thought at first that it would probably prove of little value, until turning over the leaves, I noticed that it was by no less celebrated a writer than Descartes. This author’s works were at the time little known to me, and it never occurred to my mind that this volume could be anything more valuable than a manuscript of one of his published works. However, published or unpublished, it was certainly worth a thousand times more than the dealer asked for it, so I took it back to my hotel well pleased with my morning’s work, and spent the whole afternoon reading. An entirely new idea of existence seemed opening before me, and it appeared incredible that a work of this description could have been known for two hundred and fifty years without my having even heard a repetition of the views found there.