NEW ENGRAVING PROCESS.

Globe, Volume XXIII, Issue 2336, 29 September 1881, Page 3

NEW ENGRAVING PROCESS.

(“ Melbourne Age. ”) * A new process of engraving on glass or I glassy surfaces for typographical purposes has , been invented by Mr 8. H. Crocker, and patents for it have been taken out in the ’ Australian colonies, New Z aland ard > America. Mr Crocker has, wo understand, devoted a great many years to the perfection ; of the process, and judging from the specimens we have seen ho has at last hit upon upon an excellent substitute for wood engraving at about one-third of the cost. The merits of the patant^aro—l. Its cheapness ; and 2. Its rapidity of production. An engraving which will take an ordinary wood engraver four or five days to produce can be done by this process in as many hours. In addition to this the glass would not be affected by variations of temperature like wood, and is for all practical purposes indestructible., The process, which appears a very simple one, may be described as follows -A sheetof ordinary glass, specially prepared, is placed on a sheet of white paper, and the artist, with pen and ink of a peculiar description, transfers his sketch to the glass. The ink used is composed of six parts of rosin, four parts of wax and one part of lampblack or other pigment. There is nothing novel in this composition, as it is well known that these ingredients will constitute a material which will resist the action of fluoric acid. The novelty in the application of such inky composition to a glassy surface by means of a pen kept sufficiently hot to preserve the fluidity of the composition while the drawing is being made. The pen used is a common steel one, and is kept hot either by passing a current of electricity from galvanic batteries through insulated wires connected with them, and arranged on the pen handle and holder to the point of the pen, whore the conducting circuit is impaired aud made sufficiently imperfect to cause the electricity to generate beat enough to melt the composition, or, by connecting a very small gas tube to the pen, to convey gas to a little gas burner fixed in position under the pen. The advantages to the artist in sketching on glass over wood is that, should he make any mistake, he can, by Mr Crocker’s invention, easily erase the line, whereas on wood alterations are effected with much difficulty. When the drawing has been completed on the glassy surface, it is covered with fluoric acid until those parts not protected with the ink have been engraved deep enough for the purpose required. The acid is then washed off and the drawing removed with turpentine. The sheet of glass, being ready for engraving, is fixed to a metal backing by means of shellac or other adhesive substance. The block is then complete, and may be printed direct or from electro or stereotypes, which can be taken from it as easily as from a wood block. Where the drawing is first made on paper, and then transferred to the glass, in the same way as in transferring drawings to stone for lithographic printing, the same pen and ink is used as in drawing on the glass direct, the paper being what is commonly known as transfer paper. The quality of the work depends entirely on the artist, as it reproduces faithfully his work, and he is ensured an exact reproduction of the full force and effect of the original drawing which is too frequently lost by the ordinary engraving on wood. A practically unlimited number of impressions can be produced from one engraving, and as the ink dries on the glass Instantaneously, the artist can draw any number of Hues or “ cross hatch ” as rapidly as he likes without the possibility of blurring his work ; and it is claimed for the invention that the ink used is the only one yet discovered that will resist the action of the acid and not require three or four days to dry. The skill required by the engraver in this process is not nearly so great as iu working on wood, and it may be learnt by an artist in a very short time. As an Australian invention it is one worthy of more than passing note, apart from the undoubted merit it possesses; ard the practicability of the process has been amply testified, as some of the illustrated papers of Melbourne have had impressions from these blocks, which could scarcely be distinguished from woodcuts. Numbers of testimonials have also been received from our leading firms of publishers. In an invention of this description there are sure to be defects iu the first practical application of it, but the work turned out so far is of a much higher character than might have been expected, and warrants the assumption that the process will soon rival wood engraving for clearness, aud surpass it for cheapness and durability.