the appearance of the two sides of the paper, and partly to produce a glaze or polish on the surface. In the higher-priced works, where additional labour can be paid for, the paper is subjected to hot-pressing; but under ordinary circumstances a vast pile of sheets is subjected to the action of a hydraulic press, such as is shown in fig. 7. In the office of Messrs. Clowes, where the present volume was printed, there is a hydraulic press which will exert a force of nearly 1000 tons-worked by the pressure of nothing more than five gallons of water! The beauty of a printed volume is much dependent on the pressure which the paper thus receives.

LESSON V.

BOOKBINDING.

1. In the present day, the binding of a book illustrates, almost as instructively as the printing, the power of machinery in producing elegant and useful results at a small price. Any one who compares the 'boarded' books of past years with the tasteful and convenient cloth gilt' of the present, must at once admit the superiority of the latter, even if there were equality in price; but the cloth-binding of the present day is yet more economical than the inferior paperbinding of earlier times. The shilling and half-crown volumes now so familiar to us, with their stronglycovered and neatly-lettered cloth-binding, could never have been produced without the aid of numerous improvements in the bookbinder's art. The more costly varieties have not undergone an analogous advancement. The old binders could equal anything now produced; for where neither time nor money was spared, the handicraftsman had full scope for displaying taste and refine

ment.

2. The first matter to be attended to is, to fold the sheets of printed paper. Each sheet, as has been already explained, contains 2, 4, 8, 12, or 16 leaves, or 4, 8, 16, 24, or 32 pages, according as it is called folio, 4to, 8vo, 12mo, or 16mo. Sometimes sheets are printed in still smaller and more numerous pages;

but the above five will suffice for general illustration. Whatever may be the number of pages, the sheet is folded and refolded until brought to the proper book-size. And here it is interesting to see what precision and rapidity are attainable by long practice; the folders-women and girls-are aided by nothing but a paper-knife or folding-stick; and yet they make the folds, exactly midway between the pages of type, at the rate of 300 or 400 sheets in an hour. The greater the number of pages in a sheet, the longer time does the process of folding require. A very ingenious machine has lately been invented by Mr. Black, for folding sheets and newspapers; but the bulk of the work is still, as heretofore, done by women.

3. When the sheets are folded, the collating and arranging into a book are matters of some importance. If there be 1000 copies of a work, and 20 sheets in each copy, it is obviously necessary that all the twenty in any one copy shall be different, and shall succeed each other in proper order. The printer and the bookbinder divide between them the responsibility of ensuring this accuracy. Every sheet, besides the paging, has a mark or signature (as it is called) at the bottom of the first page; this signature is generally a letter of the alphabet, and aids in identifying the sheet. In the case above supposed, there would be 1000 sheets having signature A at the bottom, 1000 with signature B, and so on. The printer would either send these sheets to the binder in this state, or he would first gather them into quires. A quire consists of one copy of sheet a, one of sheet B, one of sheet c, and so on, until there are sufficient to form the volume; insomuch that there would be as many quires (1000) as there are to be volumes prepared, each quire containing the exact materials for one copy of the work; and the folders and sewers would be careful not to disturb this arrangement.

4. Then comes the important process of sewing. If the volume is to be sold cheaply in boards or cloth, it is sewn immediately after the collating; but all bound books are previously pressed or rolled. The bookbinders of olden times were accustomed to hammer the

sheets heavily; but the hydraulic-press and the rollingpress now afford the means of producing the result much more effectively and expeditiously. In the rolling-press the sheets, six or eight at a time, are placed between tin plates, and drawn between two powerful steel rollers; they become smoother and more compressed than by any other method. The sewing is curiously managed. The sewing-press is an apparatus having a flat

bed or table, two upright bars at the ends, a cross-bar at the top, and two or more strings stretched vertically from the cross-bar to the bed. The sewer, provided with needle and thread, places a folded sheet on the bed of the press; she passes her left arm round to the other side of the press, and, by a series of alternate movements, she sews the sheet to all the strings, passing the string through to the middle fold. She then lays down

a second sheet on the first, and, with the same thread, fastens it in the same way; the strings thus constitute the medium of connexion. All the sheets in succession are thus treated, until the pile contains the proper quantity for a volume. In this manner an industrious woman can sew from 2000 to 3000 sheets in a day.

5. The back of a book has to be rounded, and the edges cut, before the covers are applied. The book is laid flat and is hammered so skilfully that the back edge shall receive a rounded or convex form: the edge has

been previously glued, and is hammered before the glue is quite dry, whereby the sheets are enabled to assume and to retain the relative positions given to them by the hammering. The back is again hammered in a different way, to form a kind of groove into which the boards may fit. The top and bottom and front edges are then cut by a machine, the most approved modern form of which is shown in fig. 9. The production of the

concave front edge is managed in a remarkable way; the book is forcibly struck with its convex edge on a table, and brought back to the flat or plane state; the front edge is then cut flat; and when the book is relieved from the press in which it has been held, the back edge springs round into its former convexity, thereby giving a concave form to the front edge. In cheaply-bound books some of the edges may be left uncut, or the back may not be rounded; but the general process is such as is here described.

6. The boards which form the stiff sides of a book are made of millboard--several thicknesses of brown paper pasted and rolled together. If the volume is to be bound, whether in 'calf' or in russia,' whether 'whole-bound' or 'half-bound,' holes are made through each board near one edge, corresponding with the strings to which the sheets had been sewn; the strings are passed through the holes, and are glued or pasted down on the inner side of the board. Many niceties of adjustment are necessary here; and when these have been attended to, the cover or leather is applied. The leather is cut to the proper size and shape, and is pasted on the boards and the back edge. If the book behalf-bound,' the leather is applied first and the paper afterwards. Many bound books have hollow backs; these are produced by pasting the leather, not upon the back edge of the volume, but upon an intermediate layer of cloth or paper.

7. Before the volume, thus far bound, can be deemed fit for the library or the drawing-room, it requires certain adornments; the production of these adornments is among the prettiest of the bookbinder's operations. The edges are generally either coloured or gilt. The colouring is called either sprinkling or marbling, according to the manner of effecting it. Gilt-edges, which used formerly to be given only to costly books, are now to be met with in very cheaplybound volumes: partly owing, it must be confessed, to the use of thinner gold-leaf than is quite consistent with the durability of the glittering ornament. The gilding of the edges is effected while the cover or case