Another point to be observed in the purchase of very expensive and valuable works is, that none of the leaves have been fac-similed. These fac-similes are done by hand, and frequently so well that they cannot be detected without the aid of a strong glass. The late Henry Stevens tells a good story of a customer of his--Mr. Lenox, of New York, the founder of the Lenox Library, and a most indefatigable collector up to the last hour of his life. "Mr. Lenox was," says Stevens, "principled against raffles, wagers, lotteries, and games of chance generally, but I once led him into a sort of bet in this way, by which I won from him L4. I had acquired a fair copy of that gem of rare books, the quarto edition of _Hariot's Briefe and True Report of the New Found Land of Virginea_ (London, Feb., 1588), wanting four leaves in the body of the book. These I had very skilfully traced by Harris, transferred to stone, printed off on old paper of a perfect match, the book and these leaves sized and coloured alike, and bound in morocco by Bedford. The volume was then sent to Mr. Lenox to be examined by him _de visu_, the price to be L25; but, if he could detect the four fac-simile leaves, and would point them out to me without error, the price was to be reduced to L21. By the first post, after the book was received, he remitted me the 20 guineas, with a list of the fac-similes, but on my informing him that two of _his_ fac-similes were originals, he immediately remitted the four pounds, and acknowledged his defeat." This Harris, whose name is prominently mentioned, was probably the greatest adept at this species of imitation who ever lived, and many important but defective works, now in the British Museum, left his hands, to all appearance, in first-rate order and condition. "Laying down" is a technical term used to express the process of re-backing a torn plate or engraving. Many of the Shakespeare folios have the portrait and verses by Ben Jonson laid down or "re-laid," as the catalogues generally describe it. This, of course, can be detected at a glance, and it may be stated positively that a laid-down plate, frontispiece, or title is looked upon as a serious blemish, inferior only to the entire absence of one or more of the three. Worm-holes, stains, fox-marks, and other flaws also detract from value; but as many of these may be removed by a judicious application of proper remedies, a special chapter will be reserved for their consideration. The market value of a book is thus composed of many elements, the chief of which is "condition"--above all things, a broad margin, and next, to that, leaves of spotless white.