... each stamped with the identical network of lines in red chalk representing his key. He proceeds to draw each color-plate successively, at all times adhering closely to the red chalk outlines, filling in with tusche where full strength of the color is required and using lithographic crayon or the stipple process to reproduce the various gradations of this color in order to secure the full color value of each printing. The register marks are ruled in on each stone corresponding to those on the key, so that the ... — The Building of a Book • Various
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