PRINTING. 



INK AND INKING-ROLLERS. 



Much of the beauty of good printing depends on 

 the quality of the ink, which it requires considerable 

 skill to manufacture. The principal ingredients 

 are boiled linseed oil and lampblack. It is made 

 of various qualities, ranging in price from is. to 

 IDS. and upwards per lb., to suit different kinds 

 of printing, from posting-bills to the finest wood- 

 cut work. Good ink should possess depth and 

 durability of colour, and be capable of drying 

 quickly after being put upon paper. 



One of the greatest of recent improvements in 

 the art of printing is in the mode of inking the 

 forms. From the days of Gutenberg, this had 

 been done by stuffed cushions, or balls covered 

 with skins, by which no regularity could be pre- 

 served, and no speed acquired. It is now done 

 with rollers made of a composition of treacle and 

 glue, which, being heated and melted together, 

 are poured into long iron moulds, in which the 

 central rod has previously been inserted. When 

 taken out of the mould, the roller is a cylinder of 

 soft and elastic matter, resembling India-rubber. 

 If required for the hand-press, it is connected with 

 a handle after the manner of a garden-roller. The 

 ink being placed, in moderate quantity, on a 

 smooth metal table, the workman draws the roller 

 backwards and forwards along the table, distrib- 

 uting a little ink equally all over its surface ; 

 and having thus diffused some ink all over the 

 roller, he applies the same to the types, drawing 

 it backwards and forwards over them, to make 

 sure that all have been inked. By this plan the 

 types are inked more equably than by the balls, 

 and in less than half the time. In modern 

 presses, however, the forms are inked by an 

 apparatus attached to the press. 



IMPROVED PRINTING-PRESSES MACHINE- 

 PRINTING. 



The first improvement upon the printing-press 

 was made near the close of the i8th century, by 



the celebrated Earl of Stanhope, who constructed 

 a press made of iron large enough to print a whole 



sheet, in which an application of levers to the 

 screw made the * pull much lighter. Other im- 

 provements followed rapidly, mostly abandoning 

 the screw altogether. Among the most prominent 

 of them was the Columbian press (see fie ei. 

 brought to this country and patented by Mr Georjc 

 Clymer of Philadelphia, in 1818. The prey- 

 ing power in this instance is procured by a lonj; 

 bar or handle acting upon a combination of ex- 

 ceedingly powerful levers (a, a, a, a) above the 

 pjatten ; the return of the handle or levers being 

 effected by means of counterpoises or weights 

 \ft C\ For ease and facility of pull, this press is 

 preferred by most workmen, and certainly the 

 powerful command which the leverage enables 

 the workman to exercise, is favourable to delicacy 

 and exactness of printing his arm feeling, as it 

 were, through the series of levers to the very face 

 of the types. 



Other presses, of a variety of styles and sizes, 

 are used in printing small forms of job-work, 

 many of these very ingenious, and working very 

 rapidly. 



Machine-printing. M.\sx all the ingenuity of 

 Lord Stanhope and that of his successors had 

 been lavished on the press, the process of print- 

 ing could not be executed without considerable 

 fatigue, and at a rate of speed seldom greater than 

 that of throwing off 250 impressions, or 125 com- 

 plete sheets, in an hour. As the taste for reading 

 increased, the necessity of more rapid production, 

 especially in the case of newspapers, stimulated 

 invention, and led to an entire revolution in the 

 structure of the press. 



In 1790, Mr Nicholson, the editor of the 

 Philosophical Journal, procured a patent for 

 certain improvements in printing, which patent 

 embodies almost every principle since so success- 

 fully applied to printing-machines. 



Whether Mr Nicholson's ideas were known to 

 Mr Konig, a German, is now uncertain ; but to 

 him is due the distinguished merit of carrying 

 steam-printing first into effect Arriving in Lon- 

 don about 1804, he first projected improvements 

 on the common press ; but after a while, he 

 turned his attention to cylinder printing, 



The first result of his experiments was a small 

 machine in which the two leading features of 

 Nicholson's invention were embraced (the cylin- 

 ders and the inking-rollers), which be exhibited to 

 Mr Walter, proprietor of the Times newspaper ; 

 and on shewing what further improvements were 

 contemplated, an agreement was entered into for 

 the erection of two machines for printing that 

 journal. Accordingly, on the z8th of November 

 1814, the public were apprised that the number of 

 the Times of that date was the first ever printed 

 by machinery steam-propelled. 



After the utility of cylindrical printing had been 

 thus proved, it was thought highly desirable th.it 

 the principle should be applied to printing fine 

 book-work, where accurate register is indispens- 

 able. Various improvements were introduced for 

 this purpose. The best of them was that patented. 

 in 1818, by Messrs Applegath and Cpwper, and 

 as the double-cylinder machine for ordinary book- 

 work is still constructed on the same model, we will 

 shortly describe it It is represented in tig. 6. It 

 is about fifteen feet long by five broad, and con- 

 sists of a very strong cast-iron frame-work, 

 secured together by two ends and several cross- 



