Aloys Senefelder, a German, is credited with inventing the process of lithography. A lithograph is a literally a picture printed with a stone (litho) plate. The process is based on the resistance of water to grease or oil. The artist creates an image on a fine grained stone with a greasy crayon or fluid substance. Water is washed across the stone and then ink is applied. The ink adheres to the greasy areas creating the image. Stone and paper are then passed together through a flat-bed press. A chromolithograph, a color lithograph, is printed with a different stone for each color. During the 1800s, stone lithography was a large industry. Giant presses were necessary to handle the size and weight of massive stones. Firms such as Currier & Ives made large color prints which are still collected today. In the 1900s, offset lithography, using thin, metal plates and high-speed printing machines replaced stone lithography.
