PLATE CXX.
In our notice of Plate XCI. we gave a brief sketch of the history of the woollen manufacture in Eng-land, describing in general terms its most characteristic processes, and particularly adverting to the chemicalprinciples involved in colour-printing, and the employment of dyes, mordants, discharges, and resists. Wewill now endeavour to convey to our readers some idea of the ingenuity with which the operation of printingboth woollen and cotton goods is conducted.
Four different modes of printing woven fabrics are practised: firstly, by wooden blocks worked by hand;secondly, by larger blocks set in a frame and worked by machines, one of which is called, from the name ofits inventor, M. Perrot of Rouen, —the Perrotine; thirdly, by copper-plates (a method now almost obsolete) ;and lastly, by engraved copper cylinders, mounted in an elaborate and beautiful machine, and capable ofprinting a pattern of several colours simultaneously.
The hand-block is the simplest, as it was the earliest, of these methods. The design being drawn onpaper is transferred to a block of sycamore wood, fixed upon a base of deal, and cut in relief, as in ordinarywood-engraving. Small slips of copper are substituted for the wooden lines, where they would be subjectedto much wear; and pieces of felt are introduced between the copper fillets, where broad patches of colourare to be produced. Each of these blocks will print only one colour, and two or more are therefore requisitefor every pattern. The cloth being wound on rollers, a portion of it is spread upon a table before theprinter, who is assisted by a boy or girl to spread the colour on a prepared elastic surface. The workman,holding his block by a handle on the back, colours its surface by pressing it upon the pigment or dye; hethen, with the blow of a mallet, impresses the coloured pattern from the block upon the cloth; and whenthe whole of the fabric has been thus printed in one colour, it receives a second portion of the pattern fromanother block in the same manner. This operation requires considerable manual dexterity, and occupies muchtime; for as the blocks measure only 9 inches by 5 inches, it requires 672 applications of each block to printa piece of cloth 28 yards long by 30 inches broad; or 2016 separate printings for a piece of three colours.
About the year 1785, woven goods were first printed from engraved copper plates, the design being inintaglio instead of in relief, on hollow rollers or cylinders; care being taken to adapt one or more completerepetitions of the pattern to the exact circumference of the cylinder. By this mode, as in block-printing,one colour only is produced from each cylinder. The labour of engraving these copper cylinders, which arefrom 30 to 40 inches long by 5 inches in diameter, was subsequently obviated by the application of Mr.Perkins’s principle of multiplying steel plates. This beautiful invention was introduced at Manchester byMr. Lockett about the year 1808, and the process may be described as follows :—A small cylinder of softsteel, about three inches long by one inch in diameter, is first engraved with the desired pattern. Thiscylinder, which is called the die, is then hardened, and by means of powerful pressure is made to transferthe device to a soft steel cylinder of the same size, on which it of course appears in relief. The latter,which is called the mill, is then hardened in its turn, and becomes the means of transferring several repe-