By "binding" a book is meant the arrangement of the "sheets" composing it, with maps, plates, etc. in proper sequence, within a pair of covers, of various material, with or without ornamentation, and in such a manner that the pages can be turned over separately without being detached. The art is divided into a number of operations.
The first step is to fold the printed sheets evenly, by laying them on a table with the "signatures" (figures or letters on the first page of each sheet) at the left side facing downwards. The sheet is folded over from right to left, carefully placing the "folios" (numbers of the pages) together, and held so while the folding-stick, carried in the right hand, is drawn across the sheet, creasing the centre. Next the folder is held where the new crease is to be made, and the top half is folded downwards in the same even manner. This order is repeated till the sheet assumes the form of a page.
Books that have already been folded, and issued in numbers, must be " pulled to pieces" or divided before binding. The parts being arranged in order, the outside wrappers are torn away, and each sheet is pulled out singly, cutting any thread used in sewing the centre of the sheet at the back. Even if the sheets have not been properly done in the first instance, refolding is not often resorted to, the previous creasing rendering the paper liable to be torn; books that have been bound and cut would be rendered worse by refolding. The "groove" is knocked down on a flat surface, after screwing it up in the laying press (the groove is the projection of the book at right angles to the back, and is where the back edge of the board or cover hinges). The edge of each sheet (from a folded work) being cleared of all adhering glue, etc, the book is ready for the next process. In large establishments folding is done by machine. A very useful auxiliary to hand folding is a revolving table carrying the sheets in succession before the gatherers.
The object of these processes is to make the book solid. Use is made of a stone or iron slab, perfectly smooth, and bedded with great solidity; and a bell-shaped hammer, weighing about 10 lb., with a short handle fitting the hand. The faces of both hammer and "stone" must be kept clean, and it is well to lay a piece of paper above and below the "sections" when beating, or the repeated concussion will glaze them. Each "section" or lot should be about J in. thick, that will be 15-20 sheets, according to the thickness of paper. The section is held between the fingers and thumb of the left hand, resting on the stone; the hammer, grasped firmly in the right hand, is raised, and brought down with rather more than its own weight on the section, which is continually moved round, turned over and changed about, in order that it may be equally beaten all over. By passing between the lingers and thumb, it can be felt whether it has been properly and evenly beaten. In each blow of the hammer, the face must fall fairly on the body of the section; if the hammer is used so that the greatest weight falls outside the edge of the sheets, the paper will break away as if cut.
After each section has been beaten, the whole are put together and beaten again.
Rolling sometimes replaces beating. But all books should not be rolled, and it is essential to know how and when to use the beating hammer, and when the rolling machine. Old books should on no account be rolled. The early printing presses exerted such pressure on the type that the paper round the margins is often 2 or 3 times as thick as the printed portion. For modern work, the rolling machine is, as a rule, better than the hammer.
For rolling, the book is also divided into sections, but fewer sheets are taken - from 6 upwards, according to the quality of the work. The sheets are placed between tins, and the whole passed under a roller, which is adjusted to the thickness of the sections and the power required, by a screw provided for the purpose. Some binders execute rolling at a small charge for others.
Each sheet or leaf must be put in its proper sequence, according to the "signatures." Plates are trimmed or cut to the proper size before being placed in the book; and maps that are to be folded must be put on * guards." A map mounted on a guard of the size of the page may be kept laid open on the table beside the book, which can be read at any part without concealing the map; this is called " throwing out " a map.
For collating, the book is held in the right hand, at the right top corner, a turn of the wrist bringing the back to the front. The sections are fanned out, and with the left hand brought back to an angle, which will cause them when released to spring forward, so that the letter on the right bottom corner of each sheet is seen and released in succession. The book must always be beaten or rolled before placing plates or maps, especially if coloured.
After ascertaining that the letterpress is perfect, the plates are collated and squared with a sharp knife and straight-edge. If printed on paper larger than the book, the plates must be cut down to the book size, leaving less margin at the back than there will be at the foredge when the book is cut. Frontispiece plates face to the left; but as a general rule, plates should be placed on the right hand, so that on opening the book they face upwards. With plates at a right angle to the text, the inscriptions are placed on the right margin, whether the plate faces to the right or left. Plates on thick paper must be "guarded," either by adding a piece of paper of the same thickness, or by cutting a piece off the plate and rejoining with a strip of linen, so that the plate works on a linen hinge. The width between the guard and the plate must equal the thickness of the paper. Cardboard plates are strengthened by putting linen at both back and front. If a book consist of plates only, sections may be made by placing 2 plates and 2 guards together, and sewing through the centre between the guards, leaving a space between the guards to form the back.