20. They are then severed in half with a cutting machine, and afterwards calendered, by passing the sheets successively between rollers; or they are pressed between smooth pasteboards. In the latter case, hot metallic plates are sometimes interposed between every few quires of the sheets. The paper, when treated in this way, is called hot-pressed. It is next counted off into half-quires, put up into reams, pressed, trimmed, and finally enveloped in two thick sheets of paper, which completes the whole process of the manufacture.
21. The manufacture of paper, as just described, seems to be a tedious process; yet with two machines and a suitable number of hands, say sixty or eighty, three hundred reams of letter-paper can be produced from the raw material in a single day. It is hardly necessary to remark, that paper is of various qualities, from the finest bank-note paper, down to the coarsest kinds employed in wrapping up merchandise, and that, for every quality, suitable materials are chosen. The process of the manufacture is varied, of course, to suit the materials. None but writing and drawing paper requires to be sized.
22. Until after the beginning of the present century, paper was made exclusively by hand, and this method is still continued in a majority of the mills in the United States, although it is rapidly going out of use. It differs from that just described chiefly in the manner of collecting the pulp to form the paper, this being effected by means of a mould, a frame of wood with a fine wire bottom, of the size of the proposed sheet. In the use of this instrument, a quantity of the pulp is taken up, and while the vatman, or dipper, holds it in a horizontal position, and gives it a gentle shaking, the water runs out through the interstices of the wire, and leaves the fibrous particles upon the mould in the form of a sheet. The sheets thus produced are pressed between felts, and afterwards treated as if they had been formed by means of a machine.
23. The first idea of forming paper in a continued sheet originated in France; but a machine for this purpose is said to have been first made completely successful in England, by Henry and Sealy Fourdrinier. Many machines made after their model, as well as those of a different construction, are in use in the United States, to some of which is attached an apparatus for drying, sizing, and pressing the paper, as well as for cutting it to the proper size. Very few machines, however, yield paper equal in firmness and tenacity to that produced by hand.
THE BOOKBINDER.
1. Bookbinding is the art of arranging the pages of a book in proper order, and confining them there by means of thread, glue, paste, pasteboard, and leather.
2. This art is probably as ancient as that of writing books; for, whatever may have been the substance on which the work was executed, some method of uniting the parts was absolutely necessary. The earliest method with which we are acquainted, is that of gluing the sheets together, and rolling them upon small cylinders. This mode is still practised in some countries. It is also everywhere used by the Jews, so far as relates to one copy of their law deposited in each of their synagogues.
3. The name Egyptian is applied to this kind of binding, and this would seem to indicate the place of its origin. Each volume had two rollers, so that the continued sheet could be wound from one to the other at pleasure. The square, or present form of binding, is also of great antiquity, as it is supposed to have been invented at Pergamus, about 200 years before Christ, by King Attalus, who, with his son Eumenes, established the famous library in that city.
4. The first process of binding books consists in folding the sheets according to the paging. This is done by the aid of an ivory knife, called a folder; and the operator is guided in the correct performance of the work by certain letters called signatures, placed at the bottom of the page, at regular intervals through the book.
5. Piles of the folded sheets are then placed on a long table in the order of their signatures, and gathered, one from each pile, for every book. They are next beaten on a stone, or passed between steel rollers, to render them smooth and solid. The latter method has been introduced within a few years. This operation certainly increases the intrinsic value of the book; but it is not employed in every case, since it is attended with some additional expense, and since it diminishes the thickness of the book, and consequently its value in the estimation of the public at large.