HOW CHROMO-LITHOGRAPHS ARE MADE.

New Zealand Times, Volume XXIX, Issue 4145, 3 July 1874, Page 3

HOW CHROMO-LITHOGRAPHS ARE MADE.

Chromo-lithography is the art of printing pictures from stone in colors. The stone used is a species of limestone found in Bavaria, which is wrought into thick slabs with finely polished surface. The drawing is made upon the slab with a kind of colored soap, which adheres to the stone, and after the application of certain acids and gums, enters into chemical- combination with it. When the drawing is completed, the slab is put on the press and carefully dampened with a sponge. The oil-color, or ink, is then applied with a common printer’s roller. The parts of the slab which contain no drawing, being wet, resist the ink, while the drawing itself being oily repels-'the water, but retains the color applied. '' In a chromo, the first proof is a light groundtint, covering nearly all the surface. It has only a faint, shadowy resemblance to the completed picture. The next proof, from the second stone, contains all the shades of another color. This process is repeated again and again, occasionally as often as thirty times. The number of impressions does not necessarily indicate the number of colors in a painting, as the colors and tints are greatly multipled by combinations created in the process of printing one over the othex’. In twenty-five impressions a hundred distinct shades may sometimes be produced. The last impression is made by an engraved stone, which produces that resemblance to canvas noticeable in all the finer chromos.

The production of a chromo, if it is at all complicated, requires several months, sometimes several years, of careful preparation. At every stage of the process equally great skill and judgment are required. The mere drawing of the different and detached parts on so many different stones is of itself a work that requires an amount of labor and a degree pf skill which to a person unfamiliar with the process seems incredible. Still more difficult and requiring still greater skill is the process of coloring. This demands a knowledge which artists have hitherto almost exclusively monopolised, and in addition to it the practical familiarity of a printer with mechanical details. “Drying " and “ registering ” are as important branches of the art as drawing and coloring. On proper registering the entire possibility of producing a picture at every stage of the progress depends. Registering is that part of a pressman’s work wliich consists in so arranging the paper in the press that it shall receive the impression in exactly the same spot on every sheet. The difference of a hair’s breadth would spoil a picture, for it would hopelessly mix the colors. The paper used is- white, heavy “plate paper,” of the best quality, which has to pass through a heavy press, sheet by sheet, before its surface is fit to receive an impression.

After the chromo has passed through the press it is embossed and varnished, and then put up for the market. These final processes are for the purpose of breaking the glossy light, and of softening the hard outlines which the picture receives from the stone. These processes impart to it the appearance of a painting on canvas.