660 PRINTING MACHINE 



T is the form of type ; i, i, are two inking-tables ; of which one is placed at each end 

 of the form. The inking apparatus is similar to that above described, with the 

 addition of two central inking-rollers B, which likewise receive their ink from the ink- 

 ing-tables. The printing cylinders 1, 2, 3, 4, are made to rise and fall about half an 

 inch ; the first and third simultaneously, as also the second and fourth. The form of 

 type, in passing from A to B, prints sheets at 1 and 3 ; in returning from B to A, it 

 prints sheets at 4 and 2 ; while the cylinder alternately falls to give the impression, 

 and rises to permit the form to pass untouched. 



Each of the lines marked t, consists of two endless tapes, which run in contact 

 in the parts shown, but separate at the entering drums E, and at the taking-off parts 

 o, o, o, o. The return of the tapes to the entering drum is omitted in the diagram, to 

 avoid confusion of the lines. 



The sheets of paper being laid upon their respective feeding-boards, with the fore 

 edges just in contact with the entering drum, a small roller, called the drop-down 

 roller, falls down at proper intervals, upon the edges of the sheets ; the drum and the 

 roller being then removed, instantly carry on the sheet, between the tapes t, down- 

 wards to the printing cylinder, and thence upwards to o, o, o, o, where the tapes are 

 parted, and the sheet falls into the hands of the attendant boy. 



This invention fully answered the purpose of ' The Times ' until the immense demand 

 upon its powers rendered it necessary to provide a machine which could work off from 

 12,000 to 15,000 copies of the paper per hour. 



Mr. Applegath, to whom the world is indebted for the invention of the printing 

 machine capable of doing this large duty, decided on abandoning the reciprocating 

 motion of the type-form, and arranging the apparatus so as to render the motion con- 

 tinuous. This necessarily involved circular motion, and accordingly he resolved upon 

 attaching the columns of type to the sides of a large drum or cylinder, placed with its 

 axis vertical, instead of the horizontal frame which had been hitherto used. A large 

 central drum is erected, capable of being turned round its axis. Upon the sides of this 

 drum are placed vertically the columns of type. These columns, strictly speaking, form 

 the sides of a polygon, the centre of which coincides with the axis of the drum, but the 

 breadth of the columns is so small compared with the diameter of the drum, that 

 their surfaces depart very little from the regular cylindrical form. On another part 

 of this drum is fixed the inking-table. The circumference of this drum in ' The 

 Times ' printing machine measures 200 inches, and it is consequently 64 inches in 

 diameter. 



The general form and arrangement of the machine are represented in fig. 1690, 

 where D is the great central drum which carries the types and inking-tables. 



This drum is surrounded by eight cylinders, K, B, &c., also placed with their nxes 

 vertical, upon which the paper is carried by tapes in the usual manner. Each of these 

 cylinders is connected with the drum by toothed wheels, in such a manner that their 

 surfaces respectively must necessarily move at exactly the same velocity as the surface 

 of the drum. And if we imagine the drum thus in contact with these eight cylinders 

 to be put in motion, and to make a complete revolution, the type-form will be pressed 

 successively against each of the eight cylinders, and if the type were previously inked, 

 and each of the eight cylinders supplied with paper, eight sheets of paper would be 

 printed in one revolution of the drum. 



It remains, therefore, to explain, first, how the type is eight times inked in each 

 revolution ; and secondly, how each of the eight cylinders is supplied with paper to 

 receive their impression. 



Beside the eight paper-cylinders are placed eight sets of inking-rollers ; near these 

 are placed two ductor rollers. These ductor rollers receive a coating of ink from 

 reservoirs placed above them. As the inking-table attached to the revolving drum 

 passes each of these ductor rollers, it receives from them a coating of ink. It next 

 encounters the inking-rollers, to which it delivers this coating. The types next, by 

 the continued revolution of the drum, encounter these inking-rollors, and receive from 

 them a coating of ink, after which they meet the paper-cylinders, upon which they are 

 impressed, and the printing is completed. 



Thus in a single revolution of the great central drum the inking-table receives a 

 supply eight times successively from the ductor rollers, and delivers over that supply 

 eight times successively to the inking-rollers, which, in their turn, deliver it eight 

 times successively to the faces of the type, from which it is conveyed finally to the 

 eight sheets of paper hold upon the eight cylinders by the tapes. 



Let us now explain how the eight cylinders are supplied with paper. Over each 

 of them is erected a sloping desk, h, h, &c., upon which a stock of unprinted paper is 

 deposited. Beside this desk stands the ' layer on,' who pushes forward the paper, 

 sheet by sheet, towards the fingers of the machine. 



These fingers, seizing upon it, first draw it down in a vertical direction between 



