There are some qualities that are common to all well-bound books. Of course abnormal books have to be treated specially, but it may generally be said that every leaf of a book should open right to the back. This means that all single leaves and plates should be attached by guards, and that no overcasting or pasting-in should be allowed, and it also means that the back should be truly flexible. The sections should be sewn to flexible cords or tapes, the ends of these should be firmly attached to the boards, and the back should be covered with some flexible material, such as leather, which, while protecting the sewing-thread or cord, shall itself add to the strength of the binding. A fine binding will have many other features added by way of refinement or elaboration, but unless it has these qualities it is likely to be an unsatisfactory piece of work. A well-bound book should open well and stay open, and shut well and stay shut. The binder can bind any book so that it will not open, but there are some books that he cannot bind so that they will open and shut “sweetly.”
Bookbinding is only one part of the larger craft of book production, and to obtain a perfect book it is necessary that the workers in each branch of the craft should have a common ideal of what a book should be, and that each should do his part in such a way that this ideal may be attained. Unfortunately it too often happens that the printers are quite content if their printing looks perfect as it comes from the press, with the result—through errors in the choice of paper or the number of leaves to a section—that the bookbinder has unnecessary and sometimes unsurmountable obstacles put in his way. A book that will not open freely and that gapes like a dead oyster when it ought to be shut is not pleasant to use, and when these faults are noticed the binder generally gets the blame. Sometimes he deserves the blame, for the fault may be his, but more often than not the fault lies with the paper. To open a book a certain number of leaves of paper must be bent, and if the paper is so stiff that a single leaf will not fall over by its own weight, the book cannot be made to open quite satisfactorily if bound in the ordinary way. By swinging each leaf on a guard it is possible to bind a pack of playing-cards into something like a book which will open and shut freely, but that this can be done is no excuse for the production of books which necessitate this drastic treatment before they can be bound satisfactorily.
William Morris, when he founded the Kelmscott Press, did more than revive fine book-printing; he established a tradition for books that were eminently bindable, and the presses that followed his lead kept up the tradition; so that we have in England a large number of beautifully printed books that are worthy of the best binding, and that impose no unnecessary difficulties on the binder.
Mr. Cobden-Sanderson did much to revive the use of the tight or flexible back. In this style the leather is attached directly to the back of the sections, and so helps to hold them firmly together. All leather-bound books had tight backs until about a hundred years ago, when the hollow back came into general use. A tight back should throw up when the book is opened; that is to say the back, convex when the book is shut, should become concave on the book being opened. This causes a certain amount of creasing in the leather, and this creasing is not good for gold tooling; but with a well-bound book the damage is not serious, and important constructional features must not be sacrificed for the sake of the decoration.
The hollow back does not crease the leather, and so is preferred by finishers, and besides it is easier to cover a hollow back neatly than a tight one; but the strain of opening and shutting, which should be distributed evenly across the back, is in the hollow back thrown on the joints, with the result that the leather is apt to break at these places unless specially strengthened, as is the case with well-bound account books.
While “flexible” backs that are truly flexible are undoubtedly the best, some binders line up their backs so stiffly under the leather as to allow little or no movement when the book is opened. This avoids the creasing of the leather and leaves the decoration uninjured, but the book will not open freely, and there is no virtue in such a tight back. Leather is chosen for binding because of its toughness and flexibility, yet binders deliberately sacrifice this last quality in order to obtain extreme neatness or to hide faults in the forwarding.
It is the fashion in some quarters to admire as the perfection of craftsmanship an exact and hard square edge to the boards of a book. This can only be got by paring the leather down till it is as thin as paper and has consequently very little strength. A softer, rounder edge is natural to a leather-covered article, and it is unreasonable to expect the qualities of a newly planed board in a material so wholly different in character. The edges of the leather-covered board should have a distinctly flat face, and clumsiness will be avoided by any good craftsman. It is only the extreme sharpness, so much admired by unknowing people, that is objectionable.
In the treatment of the edges of the leaves fashion has gone to two extremes: some book-lovers demand that the edges should be entirely uncut, while others require them to look like a solid piece of metal. The rough edges, or “deckle,” on hand-made paper is a necessary defect due to the way the paper is made. These rough edges were always trimmed off by the early binders because they were unsightly, difficult to turn over, and harboured dust. Some of the shorter leaves would usually be left untrimmed. Such short leaves are known in the trade as “proof,” i.e. proof that the book has not been unduly cut down. To gild a book-edge absolutely solid the binder must cut down to the shortest leaves and so often has to reduce the size of the book unreasonably; but an acceptable compromise between entirely uncut edges and solid gilding can be arrived at if the sections of a book to be finely bound are trimmed singly and gilt “in the rough” before sewing. This enriches the edges but does not disguise their nature nor necessitate their being unduly cropped.
In recent times there has been much good work done in England in the investigation of bookbinding materials. The Royal Society of Arts Committee on “Leather for Bookbinding” has established standards of leather that have made it possible for binders to procure skins that are uninjured in the process of manufacture, and bookbinding leather of the very highest class is now being produced in England. The leather manufacturers are able to dye leather any reasonable shade without the use of sulphuric acid, and it is only some of the lighter fancy colours that are unprocurable in “acid free” leather. That these “fancy” shades are unprocurable in uninjured leather is a distinct gain, as they mostly fade, and books bound in such leather seldom look as if they were intended to be used.
There are various ways by which leather-bound books may be decorated, but tooling, either in gold or blind, is by far the commonest, and it is tooled bindings that we are considering here. “Blind” tooling is the impression of hot tools on the leather. The most satisfactory tools for blind work are those cut die-sunk like a seal. These, by depressing the ground, leave the ornament in relief. Tools for gold work are cut so that the ornament with the gold is depressed below the surface of the leather. These tools may be used without gold, but blind tooling produced in this way has little of the character associated with this work when it was at its best, i.e. up to the end of the fifteenth century. Gold-tooling came to Europe from the East, and preserved a tradition of Eastern design for a very long period. The English gold-tooled bindings of the seventeenth and eighteenth centuries are often strangely Eastern in the style of the decoration.