Of all the library's enemies, the most terrible is fire. Water is bad enough; is it not recorded that the 450 copies of the Bible Society's translation of the Gospel of St. Matthew into Manchu, printed on the soft silken paper of China, were destroyed by an inundation of the Neva? But such damage can rarely occur, unless when the element of the Sylph is invoked to combat the element of the Salamander. The muddy waters of the Neva, also, were probably more pernicious than the "salt sea streams" would have been. We ourselves have transcribed manuscripts of Shelley's which had been for months at the bottom of the Mediterranean, and which, although protected by package, had evidently been soaked with salt water. Exposure to fire for a hundred-thousandth part of the period would not have left a letter legible.

The librarian's vigilance and resource, accordingly, ought to be enlisted against fire in an especial manner, and no contrivance should be overlooked that seems to afford the least prospect of controlling or mitigating its ravages.

On July 17, 1884, experiments were made in the garden of Mr. Bernard Quaritch, the eminent bookseller, with fire-proof cases devised by Mr. Zaehnsdorf, equally distinguished as a binder, and were reported in the Academy of July 26. Three books, each enclosed in a separate case, were put into a fire, and kept there for half-an-hour. On their being extracted, "one, which had been in a case lined with tin, unpierced with air-holes, suffered only in its binding, which had been slightly damaged, not directly by the fire, but only by the heated metal. A second, of which the case was of the usual kind, but also unpierced with air-holes, came out intact. The third, in a case resembling that of the second, but pierced with air-holes of good diameter, suffered most, the fire, and the water by which the fire was extinguished, having both found admission through those punctures, the water being the more deleterious agent of the two. This book was, however, not materially injured. From this experiment it may be concluded that a good case will in almost all instances preserve a book from destruction by fire, that a metal lining to the case is not necessary, and that the air-holes (which experiments of a different kind have proved to be indispensable) should be small and numerous, distributed over the top and front edges, and not only on the top."

In 1894, the chief part of the library of Lord Carysfort at Elton Hall, Peterborough, was destroyed by fire, these books only escaping which had been protected by Mr. Zaehnsdorf's cases. On October 3, 1896, Lord Carysfort wrote: "A few of my books which were in cases were quite preserved from serious injury, the cases having been blackened and destroyed, while the book and its binding were scarcely discoloured. Since the fire I have had all my valuable books put into cases such as you make."

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.