Aquatint: A tonal method of printmaking that is used in conjunction with linear etching. The technique was invented by Jean Baptiste Le Prince (1734-81). As in etching, the copper plate is bitten by the action of immersion in acid. Granules of acid-resist laid on the plate result in a fine, reticulated patterning when the plate is inked and printed from, thus producing an effect not unlike a wash.
There are 2 distinct methods of aquatint. In the first a dust-box is used to blow particles of resin onto the copper plate. In the 2nd the resin is dissolved in alcohol which is brushed over the plate; as the alcohol evaporates, particles of resin are left on the plate. The artist can vary the tones of different parts of his aquatint by subjecting them to bitings in the acid-bath of differing duration. The parts he wishes to print relatively light in tone can be protected by coating with stopping-out varnish, resistant to acid; those that are to print darker can be rebitten. (Michael Clarke)