Mankind are not always indebted to science for valuable discoveries and improvements in the mechanic arts. Some of the most useful arts are traceable to accidental causes, in which neither science nor learning was included. Among these may be named the manufacture of various kinds of marble and fancy paper. Little has been written upon this subject, and, with the exception of those immediately engaged in the business, very few have the least idea of the methods employed in its manufacture. This is not to be wondered at when it is known that the process of marbling or marbleizing paper is a secret known only to those engaged in the business. As this secrecy, how-ever, springs from selfish motives, and as a large number of honest, industrious mechanics now kept in the dark might turn the knowledge to some account, the veil for the first time is herewith removed.
To become an expert in the business of manufacturing marble paper, one should have a practical knowledge of colors, of their nature and chemical properties Without this but little progress can be made, unless he serves an apprenticeship at the business and gathers his knowledge mechanically. Even then, so nice are the workings of the process, he will find himself often at fault, and spend his time and labor in vain. To snake this matter plain, the mechanic should at first pay some attention to the study of nature. For example, in nature there are but three colors, which are very properly called "the primitive colors," namely, blue, red, and yellow; the rest are but tints or gradations of color, as may be seen through a prism or in the hues of the rainbow. In addition to the three primitive colors, nature also produces every variety of tint, not only in the vegetable kingdom, but in metallic and mineral bodies. The prismatic spectrum furnishes seven colors, of greater or lesser density, but sufficiently decided to be easily recognizable in an ordinary light; these are red, blue, yellow, green, orange, indigo, and violet, (or purple,) though only the three first named are original in the sun's rays, the remainder being formed from a combination of blue, red, and yellow. The combination of red and yellow forms the orange; the yellow and blue combined produce the green; the union of red and blue, by altering their component parts, results in the indigo and the violet. Mankind have come to call them the seven colors.
In a regular marble paper manufactory, colors in a dry state are pulverized and mixed with water, in a stone mortar or on a marble slab, to the consistence of a thin paste, and in this state are run through an ordinary paint-mill and ground very fine. The chemicals used in mixing the colors are then put in, well stirred, and again run through the mill. In this way they become incorporated with the color, and are not easily separated therefrom when reduced to a liquid state. The colors used in the business are as follows Burnt umber, raw umber, lamp-black, ivory-black, bone-black, Oxford ochre, burnt ochre, Bengal indigo, Caracas indigo, madder lake, rose pink, Dutch pink, yellow ochre, brown ochre, Spanish brown, raw sienna, burnt sienna, Antwerp blue, ultramarine blue, cobalt blue, whiting, flake white, Paris white, chrome yellow, chrome green, chrome orange. A number of other pigments are also used, including the various lakes, made from the cochineal-fly. The indiscriminate use of any color, however, of a perishable nature should be avoided. With, probably, the exception of indigo, all colors of vegetable origin, ground with water, lose their brilliancy when exposed to the action of the atmosphere and light. Hence the best manufacturers of marble paper use only those colors prepared from earths and minerals. These are durable, and will retain their tints as long as the paper lasts upon which they have been worked. Various shades of green, violet, purple, and orange are made by compounding two colors,and lightened to any shade by the admixture of white. White is also used to good advantage with single colors, when of themselves too transparent to give them body and opacity. When a set of colors are prepared for the work, they are reduced to a thin liquid state and placed in wide-mouthed, white crockery gallipots ready for use. The brushes ordinarily used in marbling are small sash tools; these have a small nail, with a bit of leather a third of an inch in diameter, cut round, fastened to the head and driven into the centre, forming a round cone-shaped fan, (see Fig. 1,) the better to scatter minute particles of the liquid color on the surface prepared to receive it. This surface is a mucilage that can be prepared in a variety of ways. That made from gums, is most generally used, and of these gumtragacanth and gum-egg are tlse principal. The mucilage produced from tragacanth ie prepared in a large tub or cask, cut in two, into which several pails of raw water have been poured, and a given quantity of the gum, say two pounds, placed therein to soak over night. On the following day, it will have absorbed all the water and become a thick paste. This is well beaten with a twig-broom, more water added to it, and when thoroughly dissolved, reduced to the consistence of sweet-oil and strained into a flat wooden trough. Unless the gum is pure and unmixed with other gums, there is more or less astringency in the mucilage, whirls prevents the colors from flowing over its entire surface; this is corrected by a thin solution of roachalum whirls has the effect of neutralizing the astringency. The troughs are placed on a stand or table; they are made water-tight, about five inches deep, and sufficiently large to admit from four to eight sheets of paper.
The preparation of mucilage from gum-egg is very different and requires both care and judgment. When soaked the same as tragacanth, it does not forma paste, but becomes completely disintegrated, the particies being white and resembling crumbs of bread. This gum possesses a great deal of both astringency and acidity, and will not yield a mucilage until the water in whirls it is dissolved is carefully strained from it, fresh water added, and again strained, when it is placed on a slow fire in a large iron or copper vessel, a given quantity of pearl-ash mixed with it, and left to simmer. When it commences to boil, it must be continually stirred to prevent its burning, and in due time a thick mucilage will be formed, the particles gradually disappearing until a thick pulp is produced. This when cooled is reduced to a similar consistence to tragacanth. Care should be taken not to use too much pearl-ash, as an overquantity will prevent .the veins of the marbling from closing, in whirls case the paper will not be entirely covered with the colors. To remedy this the same solution of alum or a mild vegetable acid must be well mixed with the mucilage, which nullifies the alkali without injuring the liquid. In this, also, care should be used, and only sufficient of the solution put in to neutralize the pearl-ash, an overquantity rendering tlse mucilage too watery.
Supposing the mucilage to be already prepared and in the trough, and the colors ready for use and arranged on a shelf or table on the right of the work-man, (see Fig. 2,) the colors that form the veins of the marble are carefully sprinkled, one at a time, over tlse surface of tlse mucilage, the manipulator, in holding his brush, making a pivot of the ball of Iris second finger and thumb, and using Isis dexter finger as a hammer to force the fine globules of color from the brush to the mucilage. The color whirls is to form the groundwork or principal figures of the marble is thrown on last. The paper, whirls occupies a table to the left of the workman, is then put on, in single sheets, by taking up the 'sheet by the extreme corners, bending it in the form of a bow and gradually letting it fall lightly on the surface. The colors, whicls are all floating on the surface, immediately adhere to the paper with a portion of the mucilage; the paper is then thrown over sticks and placed on racks to drip, the color remaining and the mucilage falling into a sloping trough below the rack, placed there for the purpose of receiving it.
Say that six colors are used for any particular pattern desired, five out of the six will form veins, and one (the last thrown on) the groundwork. As a simple illustration of this, the first color used covers tlse whole surface and forms no vein; the second is then thrown on, whirls displaces the first, covering the surface, forcing the first into a vein, and forming the groundwork; the third in the same way displaces the second, becomes the ground, and in turn forces the second into a vein; and so on until tlse last color designed for the groundwork is thrown on, forming five distinct veins of as many different colors, and one principal color, or marble design. A variety of mudlages is made, for small work, such as for marbling the edges of books, and little jobs that do not need extensive preparations. A simple and inexpensive mucilage is made from flaxseed, (linseed,) the material from which linseed oil is manufactured. The seed is allowed to soak over night in rain-water, and tlse next morning to simmer over a slow fire for five or six hours, stirred at intervals, and closely watched, the object being to extract the mucilage without the oil. On a quick, hot fire, oil will be thrown out, which, rising to the surface, will prevent the colors from spreading, and interfere with the after-process of glazing. When the mucilage is thus obtained, it is reduced to a. consistence the same as the gums, allowed to cool, and used without admixtures of any kind. The edges of books are marbled as follows: they are sent from the bindery with their edges cut and their covers unbound; as many as may be conveniently handled are grasped with both hands, pressed closely together, and dipped upon the surface of the mucilage, which has been sprinkled with the necessary colors. The books are held together, with their edges describing an angle, the back edge first touching the mucilage, and the whole gradually made to touch. the surface. In this way the edges of thousands of books may be marbled in one day at a comparatively trifling cost. After the books are dipped they are placed in piles on narrow slips to drip, the mucilage gradually falling away and the colors remaining. Both with paper and books, the gummy nature of the mucilage and the mixtures. used in preparing the colors, prevent the colors from rubbing off. The after-glazing also assists in preserving the colors and the design of tile marbling. The edges of books are glazed after they are bound, by placing them in a binder's work-bends press, screwed together very tight, and rubbed with a binder's burnisher, a tool made with a piece of round, polished, transparent agate at its end. The friction produced by the agate on the edges leaves a gloss which is indispensable to the finish of the book.
A simple contrivance for glazing paper after it is marbled is as follows A piece of flint rock (free from flaws) about three inches long, two and a half to three incises wide, and three fourths of an inch in thickness, is made to fit into a square block of some hard wood and ground upon a grindstone until the surface which,. is to come in contact with the paper is perfectly flat; the edges are then ground away until the surface describes the half of a circle, its whole length being still: preserved. On the opposite side of the block into which the flint is fastened, a pole, five or six feet in length, and two incises in diameter, is driven, and the remaining end made to fit loosely in a socket made in the centre of a horizontal springy board, one end of which is fastened by hinges to a stationary cross beam, and the other tied with a stout cord, which is brought down in a perpendicular line and fastened to a staple in the floor; the board, when in use, describing the figure of a bow. A block of very hard wood, a trifle wider than the flint, two feet six incises long, sawed: out to describe an inverted bow, and presenting a poliished surface, is fastened on in tlse centre of a strong wooden table, made perfectly plumb, on which the flint rests. When the pole is perfectly perpendicular, it rests in the centre of the grooved block; the paper, in single sheets, is then laid on the grooved block, the operator propelling the upright pole with the flint attached, to and fro, the whole lengths or width of the sheet. The pressure from the levered board above, and the friction of the flint over the paper, give it a beautiful gloss; the operator using his right hand to propel the pole, and his left to guide the paper, during the process of glazing. This economical and homely method of glazing, however, has its disadvantages, and in consequence is fast growing into disrepute.
The latest improvement now generally adopted in large manufactories for glazing marbleized paper is much more expensive, and considerably more intricate in design. It consists of running the paper between two cylinders or calenders of polished steel, the faces of which are kept firmly pressed together, the upper cylinder performing three revolutions to one of the lower, the revolutions being regulated by multiplying cog-wheels. These cylinders are made sufficiently long to take in the largest paper used for marbling, and are made of solid iron with a steel face, which is burnished to look as bright as a mirror. They are fitted into a stationary cast-iron frame and propelled by horse-power, hand or steam, (see Fig. 3.) Paper glazed by this process receives a more brilliant gloss and retains it better than by any other; it is also a great saver of time and labor. When much power is used in propelling the cylinders, a ream of paper (480 sheets) can be turned out in the space of ten minutes. The paper must be thoroughly dried, smoothed out, and pressed before it is glazed, as any kinks, ridges, or dampness will cause it to tear in the process.
Marble-paper makers seldom allow visitors to see them while at work, andd never when preparing their colors, this being deemed the most important secret in their business. The time has rassed, however, when this, as with all other exclusive monopolies, should be encouraged at the expense of thousands of industrious mechanics, whose limited means debar them from paying exorbitant sums for learning the business. It is for their benefit, therefore, that the present article is written and the following additional instructions given. As previously noted, to make clean and good work, all ingredients used for mixing with the colors should be ground with them; in this way they are more thoroughly incorporated with the pigments; if added afterward, when the colors are thinned for use, they dO not mix properly; they become separated and float upon the surface. The ingredients used for mixing with the colors are beef's gall, raw and boiled linseed oil, spirits of turpentine, alum, and gum-arabic, in their proper proportions. With those pigments that are considered slow driers a little litharge may be used to advantage, not sufficient, however, to interfere with the native brilliancy of the color. For those colors that are to form the veins of the marble, such as black, red, yellow, blue, green, etc., all that is necessary to use for mixing is beef's gall, in the proportion of two table-spoonfuls to a pint of color, and a little weak solution of gum-arabic; the gall having the effect of making the color spread when it falls on the mucilage, and the gum-arabic of assisting in making it permanent on the paper. For the colors which are to form the ground or principal figure, beefs gall, in the same proportion, is used, with the addition of a tea-spoonful each of raw and boiled linseed oil, spirits turpentine, and the same solution of gum-arabic. These give a softness and transparency to the most opaque colors. Alum, in a thin solution, is only used when too much gall has been mixed with the color, the object being to contract the spreading, which otherwise would make the figures of the ground. work too large, and the paper could not be used on any small work.
To imitate a conglomerate marble or puddle-stone, several groundwork colors may be used in small quantities; the brush used last should contain but little color, so that the globules may be very minute, and the figure correspondingly small; the vein colors, as previously noted, being thrown on first. The effect of this is the appearance of one color of marble being imbedded in that of another.
The combing, or feather-shaped marble, is produced by the following very simple contrivance. The colors are laid on the mucilage in the ordinary way, after which a comb, the whole width of the trough, (made of a thin strip of wood, with large needles driven into its edge at given distances apart, with an elliptic piece in the centre of its upper edge, for the hand,) is drawn slowly across the surface of the mucilage, and the paper laid on immediately thereafter. Waving, or imitating waves in marble, is also very simple, if the hands are steady. It is done by giving the paper, as it touches the mucilage upon which the colors have been thrown, a to and fro or seesaw motion; beginning with one corner of the paper and gradually finishing the sheet, the motion of the arms being kept up to the end. The effect produced is to cause waves or ripples on the surrace of the mucilage, a certain portion of all the colors being displaced thereby, or, more properly rendered, faint, by every alternate dip of the paper, as it catches the impression. As some considerable time is consumed in this process, the waved paper is sold at a much higher price. From four to eight sheets of paper, according to size, can be marbled at one impression, and as the impressions are instantaneous, the operator should be careful to lay his sheets on the mucilage just in the places where they belong, commencing at either corner of the trough, and laying the next sheet immediately alongside of the first, and so on until the whole surface is covered, the space required for any given number of sheets being regulated by a sliding upright partition at the side and end of the trough. No partition, however, should subdivide the number of sheets laid at any one impression. After removing the paper from the trough to the drying-rack, before the colors are again thrown on the mucilage, the surface should be smoothed over with a flat wooden scraper, about three incites wide, made thin, and fitting in the trough lengthwise, with two uprights about six inches long, for handles. This removes all air bubbles and particles of color left from the last impression on the surface.
As a rule, the fewer and simpler the colors used for marbling, the better; the colors thus preserve their brightness, and the mucilage is kept cleaner. Certain admixtures of color are, however, indispensable; for example, lampblack alone will never form a rich, deep black, but will, when dry, have a dingy, sooty appearance. To Obviate this a little bone or ivory black and Bengal indigo is ground up with it. Chrome yellows are seldom used alone, on account of their opacity and too great brilliancy; to subdue their brightness, make them harmonize better with the adjacent colors, and also to give them a semi-transparent appearance, a portion of Dutch pink, Oxford ochre, or yellow ochre is ground with it. With rose pink a little madder lake is used. Although chrome green is occasionally used alone, it works better mixed with a little indigo and yellow ochre.
In concluding this treatise, it is proper to remark that a great deal will depend for success upon the care and judgment employed in marbleizing paper. It is not a mere mechanical art, nor can it be ranked as One of the fine arts. With a mechanical knowledge of the business should be associated a knowledge of chemistry and some artistic taste; perseverance and practice will then accomplish the rest.
It has been intimated, in the commencement of this article, that the discovery of the process of marbleizing paper is attributed to an accidental cause; this is really the case, and to a woman belongs the honor of originating the invention. About the middle of the eighteenth century, in the city of London, a Mrs. Pendarvis, while engaged in' washing clothes on a lawn adjacent to her dwelling, had occasion to use a small bag containing a preparation of indigo-blue, which had been previously dipped in the soap-suds. A neighbor passing by at the time stopped to gossip with the housewife, the drippings front the bag in her hand meanwhile falling on the suds and soap-bubbles in her tub. After her neighbor had passed on, her attention was directed to the singular appearance of the contents of her tub, which appeared like a collection of glass marbles, reflecting and refracting all the hues of the chameleon, blue being the prevailing color. Now most women under the same circumstances would have paid no attention to this, attributing it to its proper cause, the dripping of the bag; but Mrs. Pendarvis was not a common woman. She had an inquiring mind, and spent much thought in studying causes and effects. Although she had been accustomed to see the rainbow tints, and even her own rubicund face, reflected in the soap-bubbles, it never excited her wonder; but the blue marbles—there was a real and tangible something about this that struck her for the first time; it might be turned to some account. And Mrs. Pendarvis pondered over it at her washing until her husband came home to dinner, when she mentioned the circumstance to him. Mr. Pendarvis, though a dyer by trade and accustomed to dabble in colors, laughed at his wife's foolish speculations, and, calling them castles in the air, dismissed the subject. His wife, however, was not to be put off; she knew there was something in it, and secretly determined to fathom it. Her reasoning on the subject was homely, but cogent: if one color would produce such an effect, what would two or more produce ? Her husband was a dyer; she would secure a little of his dye without his knowing it two or titres different colors, and try the experiment. It would be no harm at all events. The experiment was tried, and the bubbles were like marbles of many colors. This did not surprise her, she looked for such a result; but how to adapt it to some practical use was the question. At length, after torturing her mind for a considerable time, a bright idea struck her. Procuring a piece of white paper, she laid it gently on the bubbles, and a faint impression of motley tints was produced. A second experiment, with a stronger lye, was made, producing more decided impressions of color, and the result communicated to her son, a book-binder's apprentice. He, like his mother, saw "something in it," and in turn informed his master, showing him the impressions. Further experiments were tried at the bindery, resulting in some improvements, and here a crude sort of marbling was inaugurated. At this stage science stepped in and suggested a liquid body of sufficient resistive force to enable colors to float on its surface, and by repeated experiments, a mucilage was found to be the best medium. But to Mrs. Pendarvis attaches the first honor of the discovery.
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