These circumstances having accidentally become known to the writer, he thought it his duty to test Mr. Zaehnsdorf's cases for himself. Two of these, filled with printed papers of no value, were placed (April 1897) on a very hot fire in the writer's own study, in the presence of Mr. Zaehnsdorf and several officers of the library of the British Museum. The result was highly satisfactory. Though the cases were greatly damaged, the papers received very little injury, and this only when they were in actual contact with the bottom and sides of the cases. Had they been bound volumes, nothing would have suffered except the edges of the binding. It seems evident that Mr. Zaehnsdorf's invention well deserves the attention of wealthy collectors of precious books. There is a serious obstacle to its introduction on an extensive scale into great libraries from the expense of the cases, which at present average about a pound a piece. It is probable, however, that cases could be contrived to take books by the shelf-ful instead of single volumes. In any event, however, it would be well worth while to employ them for the protection of books of extreme rarity and inestimable manuscripts, as well as the archives of great libraries, and artistic and scientific departments in general, which, when calendared, as they must one day be if they have not been burned first, will be among the most valuable of materials for the history of culture. It is no doubt true that the best protection against fire is not any mechanical device, but the contiguity of a good fire brigade. But at Elton Hall the nearest brigade was many miles off, and, be it as near as it will, it is also true that such devices are not exposed to the negligences, misunderstandings, and other infirmities incident to mortals which may in an evil hour paralyse the operations of human agents; and that the most efficient brigade will be greatly helped by anything which, by retarding the progress of a conflagration, holds it back from gaining the mastery before the opposing forces have been fully brought into play. This important object might also be promoted by the employment of wood specially seasoned by a chemical process. Experiments made on behalf of the British Museum in the spring of 1898 have been highly satisfactory, evincing that although wood so treated will char, it will not, properly speaking, burn, and that the use of it for floors and shelving would materially impede the process of combustion. THE SLIDING-PRESS AT THE BRITISH MUSEUM[262:1]