590 CALICO-PRINTING 



revolves. Let A be the engraved cylinder mounted upon its mandrel, which receives 

 rotatory motion by wheels on its end, connected with the steam or water power of the 

 factory. B is a large iron drum or roller, turning in bearings of the end frames of 

 the machine. Against that drum the engraved cylinder A is pressed by weights or 

 screws ; the weights acting steadily, by levers, upon its brass bearings. Round the 

 drum B the endless web of felt or blanket stuff a a, travels in the direction of the 

 arrow, being carried round along with the drum B, which again is turned by the 

 friction of contact with the cylinder A. c represents a clothed wooden roller, partly 

 plunged into the thickened colour of the trough D D. That roller is also made to bear, 

 rith a moderate force, against A, and thus receives, by friction, in some cases, a 

 movement of rotation. But it is preferable to drive the roller c from the cylinder A, 

 by means of a system of toothed wheels attached to their ends, so that the surface 

 speed of the wooden or paste roller shall be somewhat greater than that of the 

 printing cylinder, whereby the colour will be rubbed, as it were, into the engraved 

 parts of the latter. 



As the cylinder A is pressed upwards against B, it is obvious that the bearers of the 

 trough and its roller must be attached to the bearings of the cylinder A in order to 

 preserve its contact with the colour-roller c. b is a sharp-edged ruler of gun-metal 

 or steel, called the colour doctor, screwed between two gun-metal stiffening bars ; the 

 edge of which wiper is slightly pressed at a tangent upon the engraved roller A. This 

 ruler vibrates with a slow motion from side to side, or right to left, so as to exercise a 

 delicate shaving action upon the engraved surface, as this revolves in the direction of 

 the arrow, c is another similar sharp-edged ruler, called the lint doctor, whose office 

 it is to remove any fibres which may have come off the calico in the act of printing, 

 and which if left on the engraved cylinder, would be apt to occupy some of the lines, 

 or at least to prevent the colour from filling them all. This lint doctor is pressed 

 very slightly upon the cylinder A, and has no traverse motion. 



What was stated with regard to the bearers of the colour-trough D, namely, that 

 they are connected, and moved up and down together, with the bearings of the 

 cylinder A, may also be said of the bearers of the two doctors. 



The working of this beautiful mechanism may now be easily comprehended. The 

 web of calico, indicated in the figure by the letter d, is introduced or carried in along 

 with the blanket stuff a a, in the direction of the arrow, and is moved onward by the 

 pressure of the revolving cylinder A, so as to receive the impression of the pattern 

 engraved on that cylinder. 



Before proceeding to describe the more complex machines which print upon cloth 

 several colours at one operation, by the rotation of so many cylinders and rollers, it is 

 advisable to give some insight into the modern method of engraving the copper 

 cylinders. These were formerly engraved altogether by hand, in the same manner, 

 and with similar tools, as the ordinary copper-plate engravings, till the happy 

 invention of Mr. Jacob Perkins, of America, for transferring engravings from one 

 surface to another by means of steel roller dies, was with great judgment applied by 

 Mr. Joseph Lockett sen. to calico-printing, so long ago as the year 1808, before the 

 first inventor came to Europe with the plan. The pattern is first reduced or increased 

 in size to such a scale, that it will repeat evenly over the roller to be engraved ; and 

 as rollers are of varying diameters, owing to old patterns being turned off, &c., this 

 drawing to scale has to be adopted for every roller, the exact circumference of the 

 roller being taken and the pattern arranged in accordance with this. This pattern 

 is next engraved in intaglio on a roller of softened steel, which is of such a size that 

 one repeat of the pattern exactly covers its surface ; generally these rollers are about 

 3 inches long and from an inch to 2 or 3 inches in diameter. The engraver aids 

 his eye with a lens when employed at this delicate work. This roller is hardened by 

 heating it to a cherry-red in an iron case containing pounded bone-ash, and then 

 plunging it into cold water : its surface being protected from oxidisement by a chalky 

 paste. This hardened roller is put into a press of a peculiar construction, called the 

 clamming-machine, where by a rotatory pressure, it transfers its design to a similar 

 roller in the soft state ; and as the former was in intaglio, the latter must bo in relievo. 

 This second roller being hardened, and placed in the engraving-machine, is employed 

 to engrave by indentation upon the full sized copper cylinder the whole of its intended 

 pattern. The first roller engraved by hand is called the die ; the second, obtained 

 from it by a process like that of a milling tool, is called the mill. By this indentation 

 and multiplication system not only has the cost of engraving been much diminished, 

 but designs and styles have been brought into requisition which by no other means 

 could have been obtained. The restoration of a worn-out cylinder becomes extremely 

 easy in this way ; the mill being preserved, need merely bo properly rolled over the 

 copper surface again. The die roller is made of such a size that its circumference is 

 exactly a fractional part of that of the mills, say one-half, one-third, one-fourth ; then 



