This press is capable of printing either from type or from stereotype plates bent to fit the curve of the cylinder. When type is used, each page of the paper is locked up on a detached segment of the large cylinder, which constitutes its bed and chase. The column-rules run parallel with the shaft of the cylinder, and are consequently straight; while the head, advertising, and dash rules are in the form of segments of a circle. The column-rules are in the form of a wedge, with the thin part directed toward the axis of the cylinder, so as to bind the type securely. These wedge-shaped column-rules are held down to the bed by tongues projecting at intervals along their length, which slide in rebated grooves cut crosswise in the face of the bed. The spaces in the grooves between the column-rules are accurately fitted with sliding blocks of metal even with the surface of the bed, the ends of which blocks are cut away underneath to receive a projection on the sides of the tongues of the column-rules. The form of type is locked up in the bed by means of screws at the foot and sides, by which the type is held as securely as in the ordinary manner upon a flat bed,—if not even more so. The speed of these machines is limited only by the ability of the feeders to supply the sheet. This machine was first used by the _Public Ledger_ of Philadelphia, and was afterward adopted by the leading newspapers of that city and New York, as well as of the chief cities of Great Britain and other countries. To obtain the best results from the largest size of this press it was necessary to employ a dozen or more hands to feed and run it. This expensive feature was largely avoided in a new machine projected by Mr. WILLIAM BULLOCK, whose press was the forerunner of several machines that may be classed under the general name of Self-feeding or Web Perfecting Presses. THE BULLOCK WEB PERFECTING PRESS. This machine is intended for printing on a continuous roll of dampened paper, which passes between a pair of cylinders (one of which is an impression cylinder, and the other a cylinder around which stereotyped plates are bent) and receives an impression on one side, and the sheet then goes forward and is printed on the other side while passing between a second pair of cylinders similar to the first, except that the impression cylinder is four times the diameter of the plate cylinder to prevent more effectually the ink from “setting off.” After being printed, and before delivery, the sheet is cut off by a fixed serrated cutting blade, the ingenious invention of Victor Beaumont of New York. A French device for making flexible papier-maché moulds rendered it possible to cast the type-plates to fit the printing cylinders. Without this auxiliary, web perfecting presses would have been useless and impracticable.