This article about how calico printing also comes from the San Francisco Bulletin of October 7, 1861.
MODERN CALICO PRINTING.--It is comparatively but a short time since the production of designs upon calico was effected by means of hand blocks, made of sycamore or pear tree wood, two or three inches thick, nine or ten inches long, and nine broad. The face of the block was either carved into relief of the desired pattern, like ordinary wood cuts, or the figure was formed by the insertion edgewise into the wood of narrow slips of flattened copper wire, and the patterns were finished with small brushes, called "pencilings."
In engraving, the first kind of roller used was made by bending a sheet of copper into a cylinder, soldering a joint with silver, and then engraving upon the continuous surface thus obtained. An improvement on this consisted in producing the pattern on copper cylinders, obtained by casting, boring, drawing and hammering. In this case, the pattern is first engraved in entaglio upon a roller of softened steel, of the necessary dimensions. This roller is then hardened and introduced into a press of peculiar construction, where, by rotary pressure, it transfers its designs to a similar roller in a soft state, and the due being in entaglio, the latter, called the "mill," is in relief. This is hardened in its turn, and, by proper machinery, is made to convey its pattern to the copper roller. This improvement alone reduced the cost of engraving on copper many hundred per cent, and what is of far greater importance, made practical an infinite number of intricate engravings, which could have never been produced by hand labor applied directly to the roller. A further improvement was made by tracing with a diamond on the copper roller, covered with varnish, the most complicated patterns by means of eccentrics, and then etching. The combination of mill engraving with the tracing and etching processes naturally followed, adding immensely to the resources of the engraver and printer in the production of novel designs. Another point of progress is the tracing of patterns on the surface of rollers, effected by machines made on the principle of the pentagraph.
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