Before drafting his binding specification the librarian would do well to consult the excellent “Note on Bookbinding” by Mr. Douglas Cockerell, published by W. H. Smith and Son, at the price of 1d. Special attention is drawn to the difference of the cost in binding according to Specification I. and II. of the Society of Arts’ Committee reproduced on pp. 20-22 of this pamphlet, and to Mr. Cockerell’s remarks on pages 9, etc.
The above stipulations should not make any substantial difference in price per volume to those libraries which already have been using high-class leather tanned in sumach, but librarians who have hitherto been content with persians, re-tanned Australians, and other cheap classes of leather must expect to pay a higher price for leather, properly tanned and guaranteed to last. Several large firms of high reputation, who are now catering for the bookbinding trade, have already turned out thousands of skins of a satisfactory nature. These firms are not only anxious to fall in with the requirements of the Society of Arts’ Report, but are desirous of removing the distrust which at present exists with regard to leather, and to reinstate this article as being the standard and natural covering for books. For permanent wear, whether for books or other purposes, leather, when properly prepared, is without a rival both for appearance and durability. It is only for the cheaper class of work that leather substitutes are formidable as rivals.
With regard to strengths of various leathers, it is somewhat difficult to lay down a hard-and-fast rule, but in general terms it may be stated that the strongest leather made is pigskin. The fibres are tough, somewhat coarse, but of great strength. The only danger is in the paring down of the skin previous to use in the binding, and therefore, by reason of its thickness, it is well to only use pigskin for the binding of large, heavy volumes where a thick leather can be used without detriment to the appearance of the book. Seal probably comes next in strength. It is tougher than goat skin, and, by reason of the quantity of natural grease which these skins contain, will in most cases remain pliable and wear longer than the average morocco. Seal is closely followed by goat skin. A special feature of goat is the hard grain which it possesses. This is specially to be recommended where much frictional wear is given to the book. Sheep and calf may be put on about the same footing. Both are extremely pliable, but I think one may safely state that books bound in sheepskin leather, if that leather be from the cross breed, Welsh, or other mountain sheep, will probably outlast calf skin. There is no doubt that calf has got into disrepute largely on account of the destructive processes used in the finishing and production of the soft, smooth-grained calf, which has of late years become so popular. Binders must understand that the velvety finish can only be obtained by an undue pulling down of the skin previous to the tanning process or an undue paring on the part of the binder. Both Russia leather and vellum, as binding materials, have done good service in the past, but have lost their old reputation for durability. For the present, librarians are recommended to use these skins as little as possible. A few words suffice to deal with skiver bindings. These are the thin grain of sheep and sometimes calf, and are at their best about equal in strength to thin notepaper, their whole texture and fibrous structure having been split off and their nature destroyed.
It must be understood that the deterioration of leather is not only caused by faulty manufacture or improper treatment in the dye-house or finishing shop. Good bindings of sound leather are frequently destroyed by the neglect of certain elementary precautions on the part of the librarian. The subject is too large to deal with fully in these pages, but librarians would do well to study carefully the detailed report of the Society of Arts’ Committee. But the following elementary rules should be observed:—Books should not be exposed to gas fumes, or to the direct rays of the sun; the temperature of the library should not exceed 70° F., the upper strata should be well ventilated, and a thermometer should be hung on the same level as the top shelves in order to advise the librarian whether the temperature is being kept within reasonable limits. Freedom from damp is, of course, an essential condition of library architecture.
The question of leather preservative compositions is dealt with in another chapter, but too much cannot be said against the use of various decoctions which are sold to librarians for coating and preserving leather bindings. Many of these contain turpentine, which has a drying, detrimental effect. Various other emulsions are on the market, but although these give the leather a soft, pleasant feel when applied, this soon dries up, the leather becoming hard and liable to crack. There may be some suitable ingredients for applying to leather bindings, but I am of the opinion that if a library is not allowed to get too hot, and a plentiful supply of pure, dry air is always present, sound leather should require no further preservative.