HOW A LITHOGRAPH IS MADE.
AFTER the lithographer has carefully studied the original drawing before him and laid out his plan, he makes a careful tracing of it on transparent gelatine, on which he indicates every line or shade or degradation, and this tracing is carefully transferred to a previously prepared stone and serves as a "key" to the entire work and for all the color stones. The work on stone is drawn with a greasy, black, chemically prepared crayon, which, by the way, has to be sharpened backward, or from the point up, as its very brittle nature will not allow of its being sharpened in the ordinary way. The greasy crayon penetrates the stone, which is then subjected to a solution of gum arabic and nitric acid, after which it is carefully washed off with water. The black drawing, however, still shows, but is now easily washed from the face of the stone with turpentine, leaving the surface, to all appearance, as clean as when the stone first came into the artist's hands. It is then dampened with water. The printer passes his roller, charged with color, over the surface, and this adheres only where the stone is dry, or in other words, where the grease of the crayon is, and this color is transferred from the stone to the paper. The same process is employed for the application of each successive color, portions of the picture being drawn on several different stones to obtain what may be called the composite tints, while others are only drawn on a single stone when the color in the picture is to be one of those directly employed.—Selected.