Triumphs of Invention and Discovery in Art and Science. Fyfe James Hamilton

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      Such is the latest marvel of the "noble craft and mystery" of printing; but it is not to be supposed that the limits of production have even now been reached. The greater the supply the greater has grown the demand; the more people read, the more they want to read; and past experience assures us that ingenuity and enterprise will not fail to expand and multiply the powers of the press, so that the increasing appetite for literature may be fully met.

      We have briefly alluded to stereotyping; but some fuller notice seems requisite of a process so valuable and important, without which, indeed, the rapid multiplication of copies of a newspaper, even by a Hoe's six-cylinder machine, would be impossible. If stereotyping had not been invented, the printer would require to "set up" as many "forms" of type as there are cylinders in the machine he uses; an expensive and time-consuming operation which is now dispensed with, because he can resort to "casts." There is yet another advantage gained by the process; "casts" of the different sheets of a book can be preserved for any length of time; and when additional copies or new editions are needed, these "casts" can at once be sent to the machine, and the publisher is saved the great expense of "re-setting."

      The reader is well aware that while many books disappear with the day which called them forth, so there are others for which the demand is constant. This was found to be the case soon after the invention of printing, and the plan then adopted was the expensive and cumbrous one of setting up the whole of the book in request, and to keep the type standing for future editions. The disadvantages of this plan were obvious – a large outlay for type, the amount of space occupied by a constantly increasing number of "forms," and the liability to injury from the falling out of letters, from blows, and other accidents. As early as the eighteenth century attempts seem to have been made to remedy these inconveniences by cementing the types together at the bottom with lead or solder to effect their greater preservation. Canius, a French historian of printing, states that in June 1801 he received a letter from certain booksellers of Leyden, with a copy of their stereotype Bible, the plates for which were formed by soldering together the bottom of common types with some melted substance to the thickness of about three quires of writing-paper; and, it is added, "These plates were made about the beginning of the last century by an artist named Van du Mey."

      This, however, was not true stereotyping; whose leading principle is to dispense with the movable types – to set them again, as it were, at liberty – by making up perfect fac-similes in type-metal of the various combinations into which they may have entered. These fac-similes being made, the type is set free, and may be distributed, and used for making up fresh pages; which may once more furnish, so to speak, the punches to the mould into which the type-metal is poured for the purpose of effecting the fac-simile.

      The inventor of this ingenious process of casting plates from pages of type was William Ged, a goldsmith of Edinburgh, in 1735. Not possessing sufficient capital to carry out his invention, he visited London, and sought the assistance of the London stationers; from whom he received the most encouraging words, but no pecuniary assistance. But Ged was a man not readily discomfited, and applying at length to the Universities and the King's printer, he obtained the effective patronage he needed. He "stereotyped" some Bibles and Prayer-books, and the sheets worked off from his plates were admitted equal in point of appearance and accuracy to those printed from the type itself.

      But every benefactor of his kind is doomed to meet with the opposition of the envious, the ignorant, or the prejudiced. "The argument used by the idol-makers of old, 'Sirs, ye know that by this craft we have our wealth,' and, 'This our craft is in danger to be set at nought,' was, as is usual in such cases, urged against this most useful and important invention. The compositors refused to set up works for stereotyping, and even those which were set up, however carefully read and corrected, were found to be full of gross errors. The fact was, that when the pages were sent to be cast, the compositors or pressmen, bribed, it is said, by a typefounder, disturbed the type, and introduced false letters and words. Poor Ged died, and left the dangerous secret of his art (which he did not disclose during his life-time) to his son, who, after many struggles for success, failed as his father had done before him." There is a tradition current, however, that he joined the Jacobite rebellion, was arrested, imprisoned, tried, and sentenced, but was eventually spared in consideration of the value of his father's admirable invention.

      That invention, after being forgotten for nearly half a century, was revived by a Dr. Tilloch, and taken up, improved, and extended by the ingenious Earl Stanhope. It is now practised in the following manner: —

      The type employed differs slightly from that in common use. The letter should have no shoulder, but should rise in a straight line from the foot; the spaces, leads, and quadrats are of the same height as the stem of the letter; the object being to diminish the number and depth of the cavities in the page, and thus lessen the chances of the mould breaking off and remaining in the form. Each page is corrected with the utmost care, and "imposed" in a small "chase" with metal furniture (or frame-work), which rises to a level with the type. Of course the number of pages in the form will vary according to the size of the book; a sheet being folded into sixteen leaves, twelve, eight, four, or two for 16mo, 12mo, 8vo, quarto, or folio.

      Having our pages of type in complete order, we now proceed to rub the surface with a soft brush which has been lightly dipped into a very thin oil. Plumbago is sometimes preferred. A brass rectangular frame of three sides, with bevelled borders adapted to the size of the pages, is placed upon the chase so as to enclose three sides of the type, the fourth side being formed by a single brass edge, having the same inward sloping level as the other three sides. The use of this frame is to determine the size and thickness of the cast, which is next taken in plaster-of-paris – two kinds of the said plaster being used; the finer is mixed, poured over the surface of the type, and gently worked in with a brush so as to insure its close adhesion to the exclusion of bubbles of air; the coarser, after being mixed with water, is simply poured and spread over the previous and finer stratum.

      The superfluous plaster is next cleared away; the mould soon sets; the frame is raised; and the mould comes off from the surface of the type, on which it has been prevented from encrusting itself by the thin film of oil or plumbago.

      The next step is to dress and smoothen the plaster-mould, and set it on its edge in one of the compartments of a sheet-iron rack contained in an oven, and exposed, until perfectly dry, to a temperature of about 400°. This occupies about two hours. A good workman, it is said, will mould ten octavo sheets, or one hundred and sixty pages in a day: each mould generally contains a couple of octavo pages.

      In the state to which it is now brought, the mould is exceedingly friable, and requires to be handled with becoming care. With the face downwards it is placed upon the flat cast-iron floating-plate, which, in its turn, is set at the bottom of a square cast-iron tray, with upright edges sloping outwards, called the "dipping pan." It has a cast-iron lid, secured by a screw and shackles, not unlike a copying machine. This pan having been heated to 400°, it is plunged into an iron pot containing the melted alloy, which hangs over a furnace, the pan being slightly inclined so as to permit the escape of the air. A small space is left between the back or upper surface of the mould, and the lid of the dipping-pan, and the fluid metal on entering into the pan through the corner openings, floats up the plaster together with the iron plate (hence called the floating-plate) on which the mould is set, with this effect, that the metal flows through the notches cut in the edge of the mould, and fills up every part of it, forming a layer of metal on its face corresponding to the depth of the border, while on the back is left merely a thin metallic film.

      The dipping-pan, says Tomlinson, is suspended, plunged in the metal, and removed by means of a crane; and when taken out, is set in a cistern of water upon supports so arranged that only the bottom of the pan comes in contact with the surface of the water. The metal thus sets, or solidifies, from below, and containing fluid above, maintains a fluid pressure during the contraction which accompanies the cooling.

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