171 



THE TIMES PRINTING MACHINE. 



MECHANICAL EXPLANATION. 



This machine is calculated to print 4,000 impressions per hour; and 

 when the steam engine is driven with greater velocity than usual, it will 

 throw off 200 or 300 more per hour. To work it, it is necessary to 

 employ four men, A, B, C, D, to lay the paper on the drums, a, 6, <?, d, 

 and four boys, E, F, G, H, to receive it at the fly boards, I, K, L, M, 

 after having received the impression. It has four printing cylinders of 

 cast iron, 1, 2, 3, 4, turned perfectly parallel, which are cloathed all 

 round with a covering of flannel wove for that purpose. These cylinders 

 revolve upon spindles in carriages, e, e, e, e, which are connected at the 

 lower part of the frame to scale-beam leavers, f, f, f, f\ they are 

 alternately raised and lowered by an eccentric working in one end of the 

 beams, to press ; and, to avoid the form, these carriages are fitted with 

 the greatest care into recesses left in the side frames, and are so made, 

 that a portion of them can be removed when it is required to renew the 

 cylinder cloths, without deranging any other part of the machinery. 

 They receive motion from two intermediate wheels, g,ff, contained in the 

 square box, h, working in the driving pinion, Z, six revolutions of which 

 are necessary to produce four sheets ; therefore, to print 4,000 per hour, 

 the driving spindle must revolve 6,000 times in the hour, or 100 times 

 per minute. This spindle is driven by a pulley and leather strap from 

 the steam engine, Y, Z. The wheels upon the ends of the two outer 

 printing cylinders, 1, 4, give motion to the two lower, laying on drums, 

 <?, d, and by the spindle N, and the co&ic^l or level wheels, which are 

 behind the machine, put in motion the two top drums, , b. The side 

 frames of this machine are about fourteen feet in length, and two feet six 

 inches in height to the level of the moving table. They are fitted with 

 great accuracy together, and made parallel, having internal projecting 

 flanches, and likewise rollers, upon which the printing table (carrying 

 the two inking tables and form) moves backwards and forwards, which 

 alternate motion it receives from an endless rack and pinion ; the rack 

 is attached to the under side of the printing table, and the pinion is a 

 fixture in the centre of the frame of the machine, and receives its motion 

 by a pair of bevel wheels from the driving spindle. The rack is made 

 with a parallel motion, by which means it is moved from one side to the 



