In the adjoining Stock-room, some two days before being printed, the paper is “wet down,” or dampened with water, and then put under powerful screw pressure of many tons’ weight, that the sheets in the process of printing may take a clear impression from the inked type. The paper, damp from the printing-press, is then taken on trucks and by an elevator to the Drying-room, and dried, that it may not tear or the printing be defaced. In the ceiling are immense frames with cross-bars, and hanging on the latter are the printed sheets drying. There is also a steam closet to be used during damp weather, and when it is required to dry the sheets quickly. Steam-pipes circulate in the closet, by means of which a high temperature is attained, and “no postponement on account of the weather.” Workmen are busy bringing in the printed sheets, and hanging them to dry, and removing those that are dried. The thorough drying of the printed sheets is most important. [Illustration: Dry-press Room.] The three work-people seen in the corner of the Dry-press room, are engaged in laying the paper in piles, with a piece of stiff, highly polished pasteboard, of the size of the sheet, placed between them. The pressure upon this pasteboard flat-iron is to be given by the hydraulic press. The sheets are placed in piles on trucks, that move upon a little railroad, by which they are conducted to the hydraulic presses, some of which are seen at the right of the picture, packed with sheets. Here they are put under powerful screw pressure of from one hundred to four hundred tons, and come out not only much dryer, but ironed smooth of wrinkles, and the indentations made by the type. Next, the pasteboard is removed, and the piles of sheets sent into the Folding-room to be folded. [Illustration: FOLDING, GATHERING, AND SEWING ROOM.] It is interesting to mark some of the avenues of employment that printing has opened to women. The working force in this room is composed almost entirely of girls. Standing by the one at the right hand in the foreground, let us watch her rapid motions! With her simple paper-folder she skillfully folds each sheet once, and smooths the fold, then with like expertness folds this doubled sheet again, and firmly smooths the thicker fold with the ever-in-hand paper-folder; and once more she folds the compact sheet into one having eight thicknesses, or sixteen pages. This is book folding, and she is guided by the numbers at the corners of the pages, or _folios_--if these numbers meet, the folding is sure to be exact. In an adjacent room is that ingenious aid of modern printing--a rapid and dexterous folding-machine, which, had it been discovered at work in Gutenberg’s office at Strasbourg, would have been proof additional that he dealt in witchcraft. [Illustration: Diagram of Pages.]