2486b. Manifold Writing[1]
The demand for a rapid and simple method of multiplying letters, circulars, &c., has led in recent years to the invention of several ingenious processes. So few copies are obtainable by the ordinary reporters' system of sheets of tissue paper, or "flimsy," interleaved with sheets of prepared black paper, that various kinds of "graphs" have been produced, by which upwards of a hundred, and in some cases many more, copies may be produced from one writing.
The "graph" process usually consists of transferring a writing made in an aniline dye on to a gelatine surface, from which, by the application of successive sheets of paper, subjected to a smoothing pressure by the hand, a number of copies may be obtained, in a manner very similar to the ordinary lithographic process. All those which may be classed as "gelatine transfer" processes are, however, open to the objection that, after a certain number of copies, the colour grows very faint.
Some other methods of manifold writing, such es the Edison, the Trypograph, the Cyclostyle, &c. (by which 1,000 copies can be taken from one writing), do not possess this fault, being based on a principle of a fine stencil on prepared paper, and squeezing ink through the minute perforations on to a sheet of paper fixed underneath. The writing in these stencil systems, however, has a "dotty" and broken appearance, displeasing to many eyes—the Cyclostyle being, perhaps, least faulty in this respect. For those who would like to make a gelatine "graph," we append the following recipe:
Six parts by weight of pure glycerine, four parts by weight of water, two parts of barium sulphate, and one part of sugar. Mix them, and let them soak for twenty-four hours; then melt at a gentle heat, stir until thoroughly mixed, and pour the composition into a tray. Any chemist will supply an aniline dye for the ink.
Both these sections were numbered 2486 in the original text.