Printing Machine. The printing-press, though much improved during the last half century by the ingenuity of Lord Stanhope and others, is quite inadequate to a rate of production equal to the present demand, The attention of practical men was consequently directed to some more rapid means of pro duction ; and as early as 1700, even before the Stanhope Press-was generally known, Mr. W. Nicholson bad letters-patent for a machine similar in many respects to those which have now come into use. Subsequently, Mr.
a German, conceived nearly the same idea, and meeting with the encouragement in this country which he failed to obtain on the Con tinent, constructed a Printing Machine. On the 28th November, 1814, the readers of the Times ' were informed that they were then for the first time reading a newspaper printed by machinery driven by steam-power. This printing-machine, though highly ingenious, was very complicated ; and the machine of Kbnig was superseded by that of Messrs. Applegath and Cowper, the novel features of which were accuracy in the register, an improved method of inking the type, and great simplicity in parts previously very complicated, Printing-machines are either single or double ; the single being that in which only one side of the sheet of paper is printed ; tho double that in which both sides are printed before the sheet leaves the machine. The single machine is used for most newspapers and that kind of printing in which it is not necessary for the two aides of the sheet to register,' that is, for the printing on one side to be exactly at the back of the other ; the double machine for books, in which it is essential that the printing on one page should correspond with the printing on the other when the sheets are folded. This important object of the register is effected by causing the parts to move at precisely the same speed. This being the principle of the register, its success will depend on of work manship in the mechanical parts. In the double printing-machines now in use, the sheet of paper is laid on the feeder, which consists of girths of linen tightly stretched by being passed round two cylinders. By the motion of this feeder the sheet is placed between two systems of tapes, which lie two and two over each other on a series of cylinders and rollers. The sheet of paper grasped be tween them is kept clean at the places in which it is in contact with them, and by the motion of the various parts is conducted under the first printing-Cylinder, and receives an impres sion from the first set of types; thence by means of two other cylinders to the second printing-cylinder, where it receives an impres sion on the other side from the second set of types. Thus printed on both sides, it is taken out by an attendant. An inking apparatus is placed at each end of the table which carries the types, and which traverses backwards and forwards under the printing-cylinders and inking-rollers. The ink, received from a reservoir by two rollers, is transferred from them to the surface of the inking-table ; the surface of the table inks two other rollers, and these, in their turn, ink the types as they pass backwards and forwards for each impression. The excellence of the printing depends in a great measure on the type being properly inked. The machines commonly used for printing books will print from seven hundred to one thousand per hour in perfect register ; and for newspapers, printed on one side only, from four thousand to six thousand per hour.
Konig's machine printed 1,800 copies of the ' Times' per hour. Messrs. Cowper and Applegath's machine of 1827 printed 5000 in an hour. In May, 1818, Mr. Applegath erected a printing-machine for obtaining the enormous number of 10,000 impressions of the ' Times' in an hour. According to a paper on this subject by Mr. Cowper, read before the institution of Civil Engineers, this beautiful machine consists of a vertical cylin der, about 05 inches in diameter, on which the type is fixed, surrounded by eight other cylinders, each about thirteen inches in dia meter, covered with cloth, and round which the sheets of paper are conveyed by means of tapes ; each paper cylinder being furnished with a feeding apparatus, having one boy tc lay on the sheets and another to take them off The inking rollers are also placed in a vertica position, against the large cylinder, upon / portion of the surface of which they distribute the ink. The ink is held in a vertical reser
voir, formed of a ductor-roller, against which rest two 'straight edges,' connected at the back, so as to prevent the ink from running out: it is conveyed from the ductor-roller by one of the inking rollers, against which it is occasionally pushed. The type used is of the ordinary kind, and the form is placed upon a portion of the large cylinder, being fixed to it in a very plain but ingenious manner : a slab of iron is curved on its under side, so as to fit the large cylinder, whilst its upper surface is filed into facets or flat parts, corresponding in width and number to the width and number of the columns of the newspaper. Between each column there is a strip of steel, with a thin edge, to print the rule '—the body of it being wedge shaped, so as to fill up the angular space left between the columns of type, and to press the type together sideways, or in the direction of the lines ; the type is pressed together in the other direction by means of screws, and firmly held together. The surface of the type thus forms a portion of a polygon ; and the regu larity of the impression was obtained by pasting slips of paper on the paper cylinders. The operation of the machine is very simple : the layer-on' draws forward a sheet of paper on the feeding-board until its edge is under a roller, furnished with tapes, which drops down and draws the sheet forward and down ward, into a vertical position, when other rollers and tapes carry it round the paper cylinder, where it meets the type, which has been inked by passing in contact with the inking rollers ; the sheet then continues its progress until it reaches the 'taker-off.' A few statistics, relative to the printing of the ' Times,' were mentioned by Mr. Cowper, from which it appears, that on the 7th of May, 1850, the ' Times ' and 'Supplement' contained 72 columns, or 17,500 lines, made up of upwards of a million pieces of type, of which matter about two-fifths were written, composed, and corrected, after 7 o'clock in the evening. The 'Supplement' was sent to press at 7 50 r.or., the first form of the,paper at 4 15 A.M., and the second form at 4 45 A.M.; on this occasion, 7,000 papers were published before 0 15 A.ar., 21,000 papers before 7 30 ear., and 31,000 before 8 45 A.M., or in about four The greatest. number of copies ever printed in one day was 54,000, and the greatest quantity of printing in one day's pub lication was on the 1st of March, 1818, when the paper used weighed 7 tons, the weight usually required being 41 tons. The surface to be printed every night, including the 'Sup plement, is 30 acres ; the weight of the fount of typo in constant use is 7 tons ; and 110 compositors and 25 pressmen are constantly employed. The whole of the printing at the Times' office is performed by three of Apple gath and Cowper's four-cylinder machines, and two of Applegath's new vertical cylinder machines.
According to recent accounts, it would ap pear that some of the New York newspapers are now printed with machines still more gigantic and complete than those employed on the Times,' and that the rapidity of printing is still greater. There is not the slightest reason to doubt, however, that if the sale of the ' Times' were to largely increase, machines would be invented to increase the rapidity of printing to any required degree. At present, the paper duty, the stamp duty, and the advertisement duty, keep the price of English newspapers much above that of the American, and unquestionably limit the demand.
A few further details illustrative of printing will be found under STEREOTYPE, and TYPE FOUNDING. •