This cloth is known sometimes as Government Specification Cloth, but is manufactured under the specific name of "Library buckram" by the Holliston Mills, "Art buckram" by the Interlaken Mills, and "Legal buckram" by the Joseph Bancroft & Sons Company. The first two are made in pieces about 40 yards long and 38 inches wide, the Bancroft cloth in pieces 43 yards long and 43 inches wide. It must be admitted that this cloth is not quite so attractive in appearance as some of the old cloths which are not so durable. Some binders claim that it is hard to use. On the whole, however, it supplies a long felt want and is the strongest cloth made that is at all attractive in appearance.
Duck
Duck or canvas, a rough, heavy cloth much the same in quality as sail cloth, is the strongest cloth used in binding, but has some very decided drawbacks which militate against its use, except when the question of strength overshadows all others. It always makes an unattractive-looking volume—some of the more fastidious librarians rebel against its use; and it readily absorbs dirt and moisture, making it disagreeable to handle if the book has been much used. Duck having a double twisted thread in the weft is much more compact and absorbs dirt and moisture much less rapidly than other kinds. It should be used on the backs (never for full binding) of newspapers and such periodicals as are too heavy to put in library or legal buckram.
Imperial Morocco Cloth
Imperial morocco cloth, manufactured by the Winterbottom Book Cloth Company in England, is made of linen thread and finished with a grain to resemble leather. The kind most used in the United States resembles a straight-grained morocco. It is an excellent cloth in appearance, as well as in durability, but its cost is 50% greater than that of the Government Specification Cloth. It may be used on semi-popular books which will not receive a great amount of use, but which should be as attractive in appearance as possible.
Water-Proof Cloths
There are several cloths which are waterproof and therefore easily cleaned when the covers become soiled. The best of these are durabline, used exclusively by Cedric Chivers; rexine and pluviusin, used almost exclusively in England; keratol, made in Newark, New Jersey; and fabrikoid, made by the du Pont Powder Company, Wilmington, Delaware. All of these cloths are said to be acid, alkali and germ proof, do not absorb grease and can be washed with soap and water. They are strong, durable cloths, but they have at first a disagreeable odor, are hard to work and hard to letter in gold. In the application of paste to most waterproof cloths, either in the process of binding or in attaching labels to the back, it is first necessary to break down the surface of the cloth or the paste will not hold. This disadvantage no longer exists in the case of fabrikoid. Keratol and fabrikoid are made to imitate leather and are frankly sold as such. Probably the use of these cloths in libraries will always be comparatively small. Because they can be easily cleaned they may be used on the sides of juvenile books, and in rare cases for full binding.
GLUE
No very definite rules can be laid down as to what kind of glue should be used. The matter must be left largely in the hands of the binder, who must see that it is strong, yet flexible; not too poor in quality nor yet the most expensive kind which is generally used on furniture. This is too brittle for bookbinding use.
The best glue for bookbinding is made from skins and shows a dark wine color in the cake. Light colored glues are made chiefly from bones and are not usually so good. To prepare glue for use, soak small pieces in water over night and in the morning melt in the glue pot. It should never be boiled. A careful binder will see that utensils are kept clean and that glue is used in the proper thickness.