Sylvester Rosa Koehler

Definition of Etching.—To be able to get an impression on paper from a metal plate in a copper-plate printing-press, it is necessary to sink the lines of the design below the surface of the plate, so that each line is represented by a furrow. The plate is then inked all over, care being taken to fill each furrow, and finally the ink is cautiously wiped away from the surface, while the furrows are... more...