PRINTING MACHINE 



659 



uniform film of ink, to be immediately transferred by them to the types. Hence each 

 time that the forms make a complete traverse to and fro, which is requisite for the 

 printing of every sheet, they are touched no less than eight times by the inking- 

 rollers. Both the distributing- and inking-rollers turn in slots, which permit them to 

 rise and fall so as to bear with their whole weight upon the inking-table and the form, 

 whereby they never stand in need of any adjustment by screws, but are always ready 

 for work when dropped into their respective places. 



Motion is given to the whole system of apparatus by a strap from a steam-engino 

 going round a pulley placed at the end of the axle at the back of the frame. 



The operation of printing is performed as follows (seajig. 1688) : 



The sheets being carefully laid, one by one, upon the linen girths, at the feeder B, 

 the rollers c and D are made to move, by means of a segment wheel, through a por- 

 tion of a revolution. This movement carries on the sheet of paper sufficiently to 

 introduce it between the two series of endless tapes at the point where they meet each 

 other upon the entering drum E. As soon as the sheet is fairly embraced between 

 the tapes, the rollers c and D are drawn back, by the operation of a weight, to their 

 original position, so as to be ready to introduce another sheet into the machine. The 

 sheet, advancing between the endless tapes, applies itself to the blanket upon the 

 printing cylinder F, and as it revolves meets the first form of types, and receives their 

 impression ; after being thus printed on one side, it is carried over H and under i, to 

 the blanket upon the printing cylinder G, where it is placed in an inverted position ; 

 the printed side being now in contact with the blanket, and the white side being out- 

 wards, meets the second form of types at the proper instant, so as to receive the 

 second impression, and get completely printed. The perfect sheet, on arriving at the 

 point i, where the two series of tapes separate, is tossed out by centrifugal force into 

 the hands of a boy. 



The diagram, fig. 1688, shows the 

 arrangement of the tapes, agreeably to 

 the preceding description ; the feeder B, 

 with the rollers c and D, is seen to 

 have an independent endless girth. 



The diagram, fig. 1689, explains the 

 structure of a machine contrived by 

 Messrs. Applegath and Cowper for 

 printing ' The Times ' newspaper ; but 

 which is now superseded by Mr. Apple- 



gath's Vertical Printing Machine. Here "" " 



there are four places to lay on the 

 sheets, and four to take them off; consequently, the assistance of eight lads is 

 required, p, p, p, p, are the four piles of paper ; F, F, F, p, are the four feeding-boards ; 



1688 



E, E, E, E, are the four entering drums, upon which the sheets are introduced between 

 the tapes t, t, t, t, whence they are conducted to the four printing cylinders, 1, 2, 3, 4 ; 



UTJ2 



