Further efforts were, therefore, directed to increasing the output of the bed and platen presses by the application of improved inking devices, sheet-feeding, and impression mechanisms. About 1825 there was constructed by D. Napier, a machinist in London, a press containing such appliances which produced six to seven hundred impressions an hour. Other presses constructed upon the same principle, but with two type-beds, two sets of friskets, two inking mechanisms—and only one platen, in the centre of the press—were made by Hopkinson & Cope and by Napier, and were known as "double platen machines," though this is really a misnomer as there was only one platen.
Napier's invention achieved the greatest popularity and came into general use. At each end of his press there was an inking device, a type-bed, and a frisket, each set of which operated alternately with the other, but either could be made inoperative if the "feeder," or "layer-on," failed to place the sheet in time. Four boys, besides the printer, were required—two to lay on, and two to take off the sheets.
When the type-bed and the frisket carrying the sheet of paper were in position under the platen, the latter was drawn downward to make the impression by means of a "toggle" joint which acted upon two strong rods, one on each side, and was then raised again by a counterbalance weight. Owing to the awkward method of handling the paper, the working speed of the press was necessarily slow, and the size of the sheets limited to double royal, or 25 × 40 inches.
The best presses of this type were those devised and patented by Isaac Adams, of Boston, in 1830 and 1836, and by Otis Tufts, also of Boston, in 1834. R. Hoe & Co., of New York, acquired Adams' business in 1858 and continued the manufacture of his presses. Over one thousand in many different sizes were made by this firm, the largest printing a sheet 33 × 46 inches at a working speed of one thousand impressions an hour. The last Adams press was made in 1882, but quite a number are still in use in prominent printing-offices in New York, Boston, and a few other cities, where the results on fine book work are still considered better than from the faster cylinder presses. The mechanical principle employed in the Adams press for exerting a flat, parallel pressure has now been generally adopted for heavy stamping and embossing presses.
To go back to the early part of the nineteenth century, when Koenig found his bed and platen press impracticable, he immediately set to work, assisted by one of his countrymen, Andreas Bauer, a mechanic who had helped him formerly, and in the latter part of 1812, the first flat-bed cylinder press was erected by them in Bensley's office. The cylinder of this press had three impression surfaces with spaces between them, and each covered with a soft blanket. With each forward movement of the type-bed the cylinder made one-third of a revolution and then came to a standstill, while the bed returned to its starting-point. The spaces between the impression surfaces allowed the type-form to pass under the cylinder without touching the blankets. At the end of the cylinder and at equal distances along its circumference were hinged three frisket frames, each fitted with tapes having reel springs at one end. The frisket frame of the uppermost impression surface rested in a vertically inclined position against the high framework of the inking mechanism. The sheet of paper was placed upon the blanket, and the cylinder then turned forward, drawing the frisket frame down with it, while the tapes, kept taut by the reel springs, adjusted themselves to the curvature of the cylinder and held the sheet upon it. After one-third of a revolution, the cylinder came to a stop to let the type-bed return. On the next forward movement of the bed and the next one-third of a revolution of the cylinder, the impression was made, and on the next repetition of these movements, the sheet was taken off by hand, and the cylinder returned to its original position to have another sheet placed on the first frisket. At every complete revolution of the cylinder and three complete reciprocating movements of the bed, three sheets were printed.
The inking mechanism was similar to that employed on the bed and platen press, but the mechanism for forcing the ink through the slit in the bottom of the fountain was improved. The inking-rollers were covered with leather as before. The type-bed was moved by a very ingenious mechanism which is in use even at the present time, and is described farther on, when the two-revolution press is mentioned. The different parts were not connected with each other, the cylinder, the type-bed, the inking-rollers, and the fountain being operated independently by separate driving mechanisms. This press printed eight hundred sheets an hour, on one side. A part of Clarkson's "Life of William Penn" was printed on this press, and was the first book ever printed on a cylinder press.
Printers and publishers were sceptical as to the practical value of this novel invention, but Mr. John Walter, the proprietor of the London Times, with better foresight than the others, and needing increased facilities for printing his paper, contracted for two presses, each to have two impression cylinders. These were constructed for him with great secrecy in a building adjoining the pressroom of the Times, and on November 28, 1814, the entire edition of that paper was printed on them,—the first cylinder presses driven by steam power.
The mechanical principles were the same as in the first cylinder press. There were two impression cylinders, but only one type-bed, and the latter had, therefore, to travel a greater distance than in the single-cylinder press. This made it impossible to obtain quite double the output of the single-cylinder press, but each of these new presses produced eleven hundred impressions an hour, a very respectable performance for that early stage. The threefold motion of the cylinders was retained, but the frisket frames were displaced, and tapes running over rollers and underneath the cylinders held the sheets against the impression surfaces. An improvement was also made in the inking mechanism by the addition of an intermediate roller between the fountain and the upper distributing cylinder roller.
The next step in advance was the construction of the first of the so-called perfecting presses, which was patented, December 24, 1814, and erected in Mr. Bensley's office in 1815 or 1816. This press had two type-beds and two impression cylinders, one of each near either end of the press. The cylinders instead of having a threefold motion revolved continuously. The circumference of each corresponded approximately to the distance traversed by one of the beds. The part of the cylinder which made the impression was a little larger in diameter than the remainder, the low portion giving the necessary room for the type-bed to return without touching it. The board from which the sheets were "fed" was near the centre of the press, and at the top adjoining the feed board was an endless belt made of cloth as wide as the board and running with an intermittent motion over two rollers.
The sheet of paper was laid upon this belt, which then moved forward, carrying the sheet between the tapes and leading it to the top of, down and around, the first cylinder where it received the first impression. Thence the sheet was conveyed by the tapes to the top of and around the second impression cylinder and was printed on the reverse side, that is "perfected," and it was then taken from the lower side of the second cylinder by hand and laid upon a board in the centre of the press, between the two impression cylinders and underneath the feed board. This press printed both sides of a sheet 21 × 34-½ inches at a speed of nine hundred to one thousand an hour.