To meet this no press has ever surpassed the stop cylinder. It has been made in several different sizes, the largest having a type-bed 45 × 65 inches. Resting upon and attached to a heavy iron foundation are two iron side frames which are securely braced together by an upper iron frame, called the "rib." This upper frame contains four tracks faced with hard steel, on which run a series of friction rollers, supporting the iron type-bed. Attached to the front of the type-bed is an iron plate, called the ink-table, its surface level with the surface of the type-form as it lies upon the bed.

At the front of the press is the ink-fountain and a number of steel and composition rollers, called the "distributing rollers." The ink is delivered a little at a time from the fountain to the revolving distributing rollers, and from them to the ink-table which moves under the rollers with the motion of the type-bed. By this means the ink is distributed upon the entire surface of the ink-table in a thin, even film. From the ink-table the ink is taken by a set of six rollers, called the "form rollers." Resting on the form rollers and moving in contact with them are additional rollers which help to distribute the ink still finer before it reaches the type.

The Building of a Book — Part 65

The impression cylinder is located at a distance from the front of the press of about two-thirds of the entire length of the press. The circumference of the cylinder is equal to the distance that the type-bed travels in one direction. When the type-bed moves from the front to the rear, the cylinder rotates in unison with it, and thus the cylinder makes one revolution. While the bed returns the cylinder does not move.

The Building of a Book — Part 65

Near the rear of the press is a large wooden board extending across the press and lying in a slightly inclined position with its lower edge almost directly above the centre of the impression cylinder. This is the "feed board" upon which the sheets of paper lie before they are printed. The impression cylinder has a set of grippers, and when the cylinder is at rest, these grippers are close to the edge of the feed board and stand open to receive the edge of the sheet of paper. Extending a little over the front of the feed board are two gauges against which the front edge of the sheet of paper is placed, while one side edge of the sheet is placed against a gauge at the side of the feed board. Just an instant before the cylinder commences to rotate, the grippers seize the front edge of the sheet, and the gauges lift out of the way. The cylinder then carries the sheet around, meets the moving inked form, and makes the impression. Before the cylinder completes its revolution, the grippers open and release the sheet, and at the same instant another set of grippers on an adjoining cylinder, called the "delivery cylinder," seize the sheet. From this delivery cylinder the sheet runs down over a set of strings, and is lifted off the strings by a sort of fan, or "sheet flier," and deposited on a table at the rear of the press. This method of delivering the sheets is known as the cylinder or rear delivery. This press may also be fitted for "front delivery." By this method the sheet of paper after being printed is carried around on the impression cylinder until the front edge comes again to the feeding point. Just as the impression cylinder comes to a stop, a set of grippers seize the front edge of the printed sheet, draw it over and away from the impression cylinder, and deposit it, with the printed side up, upon a table near the front of the press and above the ink-fountain and distributing rollers.

The Building of a Book — Part 65