6 Dr. Thomas Thomson on [Jan. 



fir board, on which a piece of sycamore is glued) on which, 

 the pattern intended to be printed on the cloth is cut. 

 The parts which are to make the impression, are left pro- 

 minent, while the rest of the block is cut away ; just as is 

 practised for wood engravings. When the pattern is too 

 complicated, and the lines too fine to be cut in wood, they 

 are made by means of small pieces of copper, drawn out 

 into narrow ribbons of the requisite fineness ; these are in- 

 geniously driven into the block, and the intervals are filled 

 up with felt. Great patience and ingenuity are displayed 

 in making these blocks for use, and calico-printers are 

 under the necessity of keeping a number of workmen, at 

 high wages, for that express purpose. 



The inventors and drawers of the patterns, constitute 

 another class of ingenious artists, in the pay of the calico- 

 printers at high wages. 



The cylinder is a large cylinder of copper, about a yard 

 in length, and four or Hve inches in diameter, upon which, 

 the pattern to be printed on the cloth is engraved. This 

 cylinder is made to revolve, and press against the cloth, 

 taking up the mordants, or colours to be printed on the 

 cloth as it revolves. By this ingenious contrivance, two 

 or even three different colours, are printed on the cloth at 

 once, and the printing proceeds, without interruption, till 

 a whole piece, or indeed, any number of pieces attached 

 to each other are printed. 



Another method of printing is almost the same as copper- 

 plate printing. The patterns is engraved upon a flat copper 

 plate, a yard or more square. Upon this plate, the colour 

 or mordant to be applied, is spread. It is then pulled. As 

 it passes along, an elastic steel plate, called a doctor, takes 

 off' all the colour, except that which fills the engraving. 

 Being pressed against the cloth in the act of pulling, it 

 prints upon it either in mordants or colours, as may be 

 the impression of the pattern. 



Whether the printing is applied by the block, the cylin- 

 der, or the flat plate, the treatment of the goods is nearly 

 the same. 



Most commonly, the printing process is employed to fix 

 the mordants upon the cloth, which is afterwards dyed in 

 the usual way. Those parts only retain the colour which 



