698 



PRINTING. 



words, mid over the intermediate cylinder H, then 

 under the intermediate cylinder I, and over a con- 

 siderable portion of the upper part of the main cylin- 

 der G. This system of tapes now leaves the main 

 cylinder G, and being made to pass over a set of 

 cullers, returns back in order to pass again over the 

 receiving roller E. The other system of tapes takes 

 the same course so far as we have described, the 

 two systems holding the sheet between them until 

 it lias received the impression from the form under 

 the second main cylinder G. The two systems then 

 pass from off the cylinder over a roller at the left 

 hand side of the boy who is represented as sitting 

 behind the driving pully X, at the centre of the 

 machine. Here the two systems separate, the one 

 being passed under a series of rollers under the ma- 

 chine and the other being led by a series of rollers 

 above it, the two systems returning by different 

 routes, where they again unite and grasp the sheet 

 to carry it through as already described. The rea- 

 son why the two systems of tapes are made to sepa- 

 rate is, that the sheet which has been carried over 

 the two main cylinders F and G may be delivered 

 upon a table in the centre of the machine, where a 

 boy is represented as sitting to receive them. The 

 mechanical reader will easily perceive, that since 

 the two main cylinders are of greater diameter than 

 the two intermediates, the latter must make a pro- 

 portionally greater number of revolutions in a given 

 time than the former, to ensure the uniform velocity 

 of the two systems of tapes throughout the process, 

 and thus prevent their sliding and the consequent 

 derangement of the register. The uniform velocity 

 of the surfaces of the main and intermediate cylin- 

 ders, is obtained by connecting them together by a 

 series of wheels, with appropriate numbers of teeth, 

 the principal of which wheels are represented in the 

 engraving. 



Having now considered the simple yet ingenious 

 manner in which the two systems of tapes are ad- 

 justed, in order to procure an accurate register, a 

 point of the highest importance, we shall next draw 

 the reader's attention to the carriage, before alluded 

 to, on which the two forms of types are laid. 



The carriage corresponds in office to the table 

 of the common hand press, being the bed or table 

 upon which the forms of type are laid. The opera- 

 tion of the machine requires that it should have an 

 alternating horizontal motion, which is obtained by 

 mounting it upon castors or wheels that move upon 

 two rails or guides firmly fixed to the frame of the 

 machine. This reciprocating motion of the carriage 

 is performed by a pinitin turning in an endless rack 

 below, the teeth of the pinion acting on the teeth 

 of the upper part of the rack to drive it forward, 

 and again on the teeth of the under part to cause 

 it to return. This part of the apparatus is too 

 minute to be represented in the engraving, but this 

 is of the less consequence, as it is a contrivance 

 well-known to every mechanic, as being one of the 

 simplest and most effective methods of converting 

 a continuous circular motion into a rectilinear al- 

 ternating one. This rack derives its motion from 

 the wheels Q and P, driven by the main cylinder G, 

 the motion thence being conveyed to an upright 

 spindle by the intervention of bevelled wheels. The 

 rack apparatus is connected to the carriage by a 

 simple arrangement of levers. The carriage thus 

 moving alternately backwards and forwards, carries 

 the two forms of types, (which are securely fixed 

 upon it at a proper distance,) alternately under the 

 main cylinders F and G, which give die impression. 

 The adjustment of the two forms upon the carriage 

 must be properly made; otherwise the register will 

 be destroyed. 



By no means the least important or least ingeni- 

 ous department of the printing machine, is the ap- 

 paratus for furnishing and distributing the ink. 



This is mainly if not entirely the invention of Mr 

 Cowper. It is performed by means of rollers co- 

 vered with an elastic composition of treacle and glue, 

 formerly alluded to, and to which he thus refers in 

 a lecture delivered by him on the recent improve- 

 ments in printing, delivered at the Royal Institution 

 in February, 1828. " The hand inking roller, and 

 distributing table, now so common in every printing 

 office in Europe and America, is my invention, and 

 is included in my patent. The decided superiority 

 of the inking apparatus in our machine over the balls 

 used in the press, induced us immediately to apply 

 it to the common press, and with complete success. 

 The invention, however, was immediately infringed 

 throughout the kingdom ; and it would have been 

 as fruitless to have attempted to stop the infringe- 

 ment of the patent, as it was found in the case of 

 the Kaleidoscope." This is one instance among the 

 thousands that might be adduced, to show the defi- 

 ciency of our patent laws; for, independently of the 

 original cost of taking out a patent, the expence of 

 defence is so great, that when the cases of infringe- 

 ment are numerous, the cost is beyond the 

 capital of the most wealthy manufacturing company 

 in the kingdom. 



The maintenance of accurate register is, as has 

 been already observed, a most important object to 

 be attained in the process of printing, and we have 

 considered the very simple and ingenious contriv- 

 ances by which this object is accomplished. A 

 point not less important in the art of printing is, the 

 uniform and proper distribution of the ink upon the 

 types. The machine we are now describing has 

 two forms of types, each of which requires a distinct 

 inking apparatus ; there are therefore two sets of 

 the inking department, entirely similar to each other, 

 one situated at each end of the machine. The ink- 

 ing rollers are seen at S, in Fig. 3. plate LXXVII. 

 But the action of the whole apparatus will be more 

 clearly understood by a reference to the side eleva- 

 tion of an improved form of the machine, shown in 

 Ffg. 4. 



The ink is contained in a box, I, at the end of the 

 machine, in which box there revolves an iron cylin- 

 der, polished, and stretching across the whole 

 breadth. In the same box there is an iron plate, 

 whose edge is ground accurately so as to be parallel 

 to the surface of the iron roller, which plate is cap- 

 able of being so adjusted, by means of a screw, that 

 its edge may be brought to any required point of 

 nearness to the iron i oiler. The ink lies upon this 

 plate, which is placed in an inclined position, in 

 order that it may fall down upon ihe iron roller; 

 but the edge of the plate is brought so near to the 

 roller, that only a small portion of the ink can pass 

 between the edge of the plate and the roller. This 

 secures uniformity in the delivery of the ink. This 

 part of the apparatus is seen at N, in Fig. 3. Im- 

 mediately below these, there is a composition roller, 

 moved by an eccentric on the axis of the main 

 cylinder, the connection being made by a side lever, 

 as may be seen in Fig. 3. at n. By means of this 

 eccentric motion, the roller we are now speaking 

 of revolves upon a crank, in such a way that it rises 

 and comes into contact with the iron cylinder in the 

 box I, and remains in contact while the carriage is 

 moving from it ; but whenever the carriage begins 

 to return, this eccentric roller falls and presses upon 

 the iron table K at the end of the carriage. The 

 ink received from the iron cylinder or roller is thus 

 transferred to the table of the carriage; but in order 

 to accomplish an equal distribution upon the table, 



