A planographic method of printmaking based on the antipathy of grease and water. Invented in Munich in 1798 by Aloys Senefelder, lithography involves drawing or brushing the design with a greasy, lithographic ink on to a specially prepared and smoothed limestone which is kept moist. The stone (lithography means ‘drawing on stone’) is then inked with lithographic ink which only adheres to those areas of the stone previously fixed with lithographic ink, the rest of the ink is repelled by the water. The stone is then printed from in a flat-bed lithographic press. Lithography was particularly popular in Germany, France, and England in the early to mid-nineteenth century for reproducing topographical drawings and watercolours in publications devoted to landscape. It also attracted some of the great masters of Romanticism such as Delacroix and Géricault. Later in the century it was taken up by a number of the most distinguished French artists including Manet, Redon, and, above all, Toulouse-Lautrec. Lithography was used throughout the 20th century by some of the most distinguished artists including Braque, Picasso, and Miró. It should be remembered, however, that the actual production and supervision of printing lithographs is normally undertaken by specialist printers and not the artists themselves. Original drawings could be made by the artists in lithographic chalk or ink on a sheet of transfer paper which could be laid down by the printer on to the printing surface and the design transferred. Alternatives to limestone as a printing surface included zinc (from about 1830) and aluminium (from about 1890). A recent development, offset lithography, involves the picking up of the design by a rubber roller from the original lithographic stone or plate. Large print-runs can then be easily and rapidly made from the roller and, because the original image has been ‘reversed’ twice, it prints the right way round. Offset lithography has all but replaced the traditional technique of letterpress for book printing. Lithographs printed in a combination of different colours are known as chromolithographs.
http://www.metmuseum.org/toah/hd/lith/hd_lith.htm Description and illustrations on Metropolitan Museum of Art website.