What is "Lithograph" Printing?

This is possibly the most widely used form of image printing to-day and is familiar to every body through newspaper and magazines where half-tone images are used. It was invented in the late 18th century by A. Senefelder a French printer, who exploited very cleverly the reluctance of oil and water to mix.

In the early lithographic prints the image was drawn on to a smooth, porous limestone block with a greasy ink or crayon. The stone was then washed over with clean water which ran off the greasy areas. The stone was then inked with a roller and the greasy ink attached itself only to the drawn image. A piece of paper was then laid over the stone and pulled through a press. The resulting image, now transferred to the paper, was printed in reverse. The modern development of the process has seen the extensive use of zinc
plates replacing the limestone blocks and massive industrial presses
producing images by the offset process and in full colour and at a fantastic speed. The offset process, incidentally, picks up the image from the zinc plate on to a roller which immediately transfers it to another roller before it is pressed down on to the paper - thus avoiding the image appearing in reverse. Neat. This makes me feel like a relic from the 19th century but my Fine Art course at Kings College Newcastle included a minor course in printmaking where we had to grind old images off limestone printing blocks until they were smooth and immaculate and ready for us to use again. I still have a lithography print of a life drawing I did directly on to the stone in the life-room at Newcastle. By heck they don't teach art like that nymore!