An intaglio printmaking technique that creates watercolour-like tone. A metal plate is sprinkled with powdered resin, heated and submerged in acid. Areas that aren't protected by resin are ‘bitten’ by the acid, creating recesses. The resin coating is removed and ink is rubbed into the recesses. Damp paper is then laid on the plate and run through a press that squashes them together and transfers the ink onto the paper.