GRAPH'OTYPE is one among numerous modes invented within the last few years of producing an engraved surface from which printing can be effected by the ordinary press. Line-engraving, mezzotiuto engraving, aquatint, and etching present the design or picture in intaglio on a metal plate, the lines being cut, and therefore below the sur face of the plate; they cannot be printed by ordinary typography, because the ink-roller inks the parts that ought to be left clean, and leaves the lines of the device untouched. Wood-engravings, and stereotypes and electrotypes taken from them, can be printed side by side with type in the same page, and by the same operation; and hence the vast extension of this mode of illustrating books and newspapers. The inventors of grapho type are trying to introduce a cheap substitute for engraved wood-blocks. Mr. De Witt Clinton Hitchcock, a draughtsman and wood-engraver, having occasion for a little enamel white powder, scraped some from the surface of a visiting-card, and then observed that the ink-lines remained just as distinct and prominent as before, not having been removed by the scraping. This slight incident suggested the new process—sketching the design on a chalky surface, and brushing away the chalk from between the lines. Mr. Hitch cock's first experiments were partially successful, ;nd he then received aid from others in establishing a mocha operandi. In the latest form of the process, after many inter mediate experiments, the block is superseded by a zinc plate covered with finely pounded French chalk, brought to a hard and very fine texture by enormous pressure, with a glossy surface produced by an interposed steel plate. On this white surface, sized
and dried, the picture is drawn with camel or sable hair pencils, dipped in an ink made of glue and lampblaCk. When dry, the white or uninked portions are rubbed down by means of a small fitch-hair brush, and pads covered with silk velvet. The rubbing is continued until the white is sunk sufficiently below the level of the inked picture or design. The plate is then saturated with liquid glass or silicate of soda, which converts the French chalk into a kind of marble. The success with which all the white is rubbed down between the inked lines, depends on a variety of circumstances—the hardness of the white, the evenness of the surface, the completeness of the petrifying action by the silicate, the protecting power of the ink or varnish, the quality of the brushes and rub bing-pads, and the careful management of the rubbing itself. Whether the fine lines of the device can be preserved from breaking up into saw-like irregularities, and whether the numerous requirements and qualities of a wood-engraving can be successfully realized, a long course of trial can alone show. The matter has been taken up by a company.
(Uncaria procumbens), a procumbent plant of the same genus with the gambir (q.v.), a native of south Africa. The seed-vessel has many hooked thorns, and clings most tenaciously to any animal—a provision for the distribution of the seed. When it lays hold of the mouth of an ox, Livingstone says, the animal stands and roars with pain and a sense of helplessness.