The progress of the marbling art, from technical scientific principles
Part 2
A size when too thick, allows the colors to expand only with great difficulty and demands a three fold larger quantity of gall than when it possesses its normal consistency. It is very difficult to remove from a too consistent size the remnants of colors.
They always unite with the size and in this way the size not only becomes soiled but it is impregnated with a large quantity of gall. As I said before, the colors should always be prepared on a separate size which can be poured into a flat vessel as it is nearly impossible to prevent several drops of color sinking to the bottom.
If this precaution be taken and if the colors are prepared according to their relative expansibilities as they are used in the order prescribed, the process will not meet with any obstruction or difficulty. As the size plays such an important part in marbling, great attention must be paid to its preparation if it is desired to make a good base for the colors. I especially recommend to laymen that they direct their attention to the consistency of the size, as this is always the key to the production of good edges.
The different peculiarities of the varieties of sizes, viz; evaporation, influence of temperature, starry formation of colors, formation of angular scales in comb-edges, and all other things which have influence on colors, will be treated of in a special article on the varieties of size.
CARRAGEEN MOSS.
CARRAGEEN MOSS.
The Carrageen or Iceland moss, or lichen is one of the algae of the sea. Chondrus Crispus grows on the cliffs of the Atlantic Ocean and the North Sea. Carrageen smells slightly of iodine and when uncleaned tastes offensively salty. Like all seaweeds it contains a great quantity of mucilage and small quantities of salts of iodine and bromine. When washed in sweetened water it becomes nearly tasteless and is without smell. On account of the great quantity of mucilage contained in it, and of its action as an alleviative to pulmonary complaints it has found many applications in medicinal practice and is given to the patient boiled in water, milk or bouillon or as gelatine in cases of coughs and diarrhoea, being a slightly nutritious substance.
The carrageen moss or Iceland moss or weed is a lichen and consists of a tuft of flat deeply divided cartilaginous fronds of an olive brown, sometimes yellowish or reddish white color; the tuft is sometimes 2 to 5 inches long.
The moss is used in many ways; as size for marbling edges, for clarifying beer, as linen-weavers starch, for finishing cloth and in the production of iodine.
The good pure carrageen is horn-like, yellowish-white, contains a great quantity of mucilage and gives the best size for marbling, as it complies with all the requirements of a good size. It is homogeneous, of great consistency, not extraordinarily viscous and cheaper than all the other materials containing mucilage which are used for marbling, but is inferior to gum tragacanth as far as durability is concerned, and that it must be subjected to boiling, but this trouble is amply repaid by the beauty of the productions.
On this size all varieties of edges can be produced, and by its diaphanous watery mucilage it gives an excellent ground to work upon.
The preparation of carrageen size is confined to one ever recurring manipulation, which must be repeated every eight days, if an always good and useful size is desired; the expenses are very trifling, a few cents for the best kind of carrageen. If bought in larger quantities the expenses for carrageen can still be reduced. For the preparation of the size take a new pot, which must always be used for this purpose exclusively, pour in six quarts of water, which quantity is sufficient to twice or three times fill the usual marbling trough, add 2-1/2 ounces of Carrageen moss and boil until the water bubbles up several times. A longer boiling is injurious because the mucilage becomes flaky and muddy. 2/5 of an ounce of Carrageen to one quart of water is fully sufficient to produce a consistent size, provided that only the best Carrageen is used.
Soft water or rain water was formerly used exclusively for preparing the size, as by using it a greater durability was obtained.
During my researches, regarding the durability of the varieties of sizes, I found means by which the influence of hard water on the ground can be suspended, so that spring and pump water can now be used without any danger.
Every kind of hard water contains mineral salts, spring water especially containing lime in smaller or larger quantities. This can be seen, when the soap, which is used in such water, curdles, because of the ingredients of soap stearine palmitic or fatty acids of sodium or potassium, form a combination with the lime, to carbonate of lime, and the potash soap is converted into an insoluble lime soap. If we add to hard water a quantity of sodium or potassium, the carbonate of lime is precipitated as a white or yellowish powder, according to the quantity of iron contained in the water, and a soft water remains.
The sun produces on a great scale in nature, what the chemist achieves on a smaller scale by evaporation or precipitation and cooling of steam, a water free of all mineral salts, which we call distilled water. Rain water is the same, but the flowing water derived from a river already contains mineral salts in greater or smaller quantities, which are brought into it by different springs and substances. The water gained by precipitations is considered soft. Carbonates of sodium or potassium are strong bases, exactly the opposite of acids, and they therefore prohibit the oxidation in plant mucilages. This chemical reaction against the formation of acids I used for the purpose of prohibiting a deterioration of the size by adding sodium, in which I was thoroughly successful, as it can easily be preserved in a cool place for even eight or ten days.
Two obstacles offered themselves, which I have overcome after a tireless and thorough investigation, first the strongly alkaline property of the size which was generated by the added carbonate of sodium and second the fermentation of lactic acid which occurred notwithstanding the sodium and made the size useless.
The presence of alkalies was injurious to such colors, chemically bound to bodies, among which red is most affected. The coloring matter was removed from the bodies and became mixed by running with the size, causing the size to become soiled. Even the shade of the color was changed to another which was nearer to purple, and in this way, the beauty of the color was greatly lessened. The second obstacle is the fermentation of lactic acids which always occurs where starch flour is in the solution, causing in consistent sizes a gradual thinning out and even a destruction of the size.
It was not my aim to save the size from destruction forever, as this is impossible (laws of nature cannot be obliterated at will) but to keep it useful for a certain period of time, and this I achieved after many experiments by using borax.
Borax is a neutral salt of strongly antiseptic properties, prohibiting fermentation and decomposition where neither base nor acid predominate. Borax is produced by neutralization of boracic acid with carbonate of sodium and can be bought at every drug-store.
This salt is sold in crystals of the size of walnuts; for our purpose it is ground to powder and is kept for use in a closed vessel. The size is first used without any addition of borax as it is then better adapted for producing comb and other drawn edges, and only after some time has elapsed, in summer 36, in winter 48 hours, are 150 grains of borax added to the size, whereupon the size, having been repeatedly stirred to dissolve the salt, will keep entirely good and useful for a period of eight days without doing any harm to the colors. On a size which contains borax, the colors expand in a much greater degree than upon unadulterated size, without impairing the consistency of the mucilage. An unadulterated size is therefore, better for marbled and veined edges, but if it be desired to produce only marbled and veined edges on the size, it is advisable to add borax to the water before boiling the carrageen moss.
As the influence of temperature is important in marbling, and the production of beautiful edges is often jeopardized by it, it should therefore have the most careful attention. Every glutinous mass acquires, according to the difference of the temperature of the size and air, in one-half to one-quarter of a minute, a film (top) which forms through natural evaporation.
On a size which has such a film, or top, the colors do not spread out in such circular forms as on a size on which the colors are quickly thrown right after the film (top) has been taken off, but form star-like veined spots which are torn by the film in all directions.
Even in the normal expansion of the drops of color, it often happens, that the rim of the drop is jagged, the cause being that the size already possessed a thin top, which was not yet sufficient to prevent the expanding of the colors. If the size be left standing for a half-hour or an hour before throwing on the color without having at first removed the top of the size, the drop will tear a hole into this film and will sink, even if quite a large quantity of gall had been added. This explains the contraction and the sinking down of colors on a still warm size, inasmuch as the top is formed by evaporation of the warm mucilage, so quickly and so thick, that the color which had already begun to spread out is pressed together by it and is forced to sink.
The greater the difference of temperature between the size and air, the quicker is the top formed. It is therefore a rule, that the size should be allowed to cool off in the same room, in which the marbling occurs, because in this way a symmetrical degree of heat or cold of the size and air will be gained. On such a size, the formation of the top is much slower and thinner, so that even after one to one and a half minutes after removal of the top of the size, the colors can be thrown on without the occurrence of the starry formation.
I will here mention a fact to show the importance of temperature. As this point has given me much trouble and has taken much time and labor, it was my aim to find that mysterious effect which I was unable to overcome despite my numerous chemical experiments, until my eyes became opened and I saw accidentally that this obstacle was the difference of temperature of size and air. From that time on I was able to prosecute my labors without the slightest difficulty.
To show the excellence of my marbling colors, I used a great number of samples, perhaps several thousand, and in order to produce them I worked on Sunday so that I could employ my whole time to the good purpose. It was winter; on every Saturday I ordered two pots of size to be boiled, and to cool them off I placed them in a room, in which there was no heat. On Sunday morning I filtered the size through a loose linen cloth; it was as clear as crystal, it possessed the necessary consistency, and I was much pleased with the results, which I had expected to achieve.
I commenced the preparation of the colors in a separate flat vessel, using but little size, so as to keep the rest from being soiled, but I was greatly astonished, when the colors in spite of the addition of gall, which of course was carefully done by drops, first spread out and then again were contracted, the starry formation of the colors took place, whenever I was not quick enough after the taking off of the top to throw on the colors.
I was dumbfounded and could give no explanation for it; the size was sufficiently cooled off, it had been standing the proper length of time, the mucilage was excellent but in spite of all that, these difficulties occurred.
Thinking that I might be more successful, if I should do the marbling in the trough where there is more surface offered to the color to spread out, I filled the trough with size of a sufficient height and then commenced the marbling, but immediately after the first trial I instantly recognized that even here my experiments would have the same result. Although I threw on the color with great alacrity, right after the top had been taken off, the first drop spread out normally 4 inches, the second but three, the third two, and the fifth and sixth only one inch. In this way I received instead of an equally wide band of thrown on color, one which tapered to a point. If I had not worked according to the system which I shall describe in the chapter of throwing on of colors, I would have received already with the fourth drop, a star-like formation.
Whatever I did to avoid this obstacle was worthless, it was and remained a mystery and I was unable on that day to produce anything beautiful or worthy of consideration. This happened several times until, by accident, and through careful study I found the cause which was nothing but the fact, that the size was much colder than the air in the room in which I worked. The evaporation on the surface of the size was so great, that the top was formed nearly as quick as on warm size and therefore a favorable result was impossible.
Another abnormity which arises from cold temperature acting on the size is the fig-like formation occurring during the drawing of the colors. The cold in some way seasons the surface; this surface becomes mixed in filtering with the liquid part of the size in numberless small particles which although the size is well stirred up in the trough by the fingers, are not dissolved and this hinders the drawing of the colors.
They adhere to the stylus and follow it and arrange themselves between the color lines in a way similar to a green fig, having a broad upper and a pointed lower end. Such an edge traversed by the comb will give an ugly result. A difference of temperature of the size and the air can also occur when the working room is suddenly heated, or, when in summer time, the size is kept in a cold cellar. To effectively obviate this difficulty it is necessary to bring the temperatures of the air and size carefully to the same height which is made easy by leaving the size, after boiling, in the room, where the marbling is executed.
In winter, when the room is heated, the size should be poured into the trough one hour before using, in summer the thing regulates itself because it is then unnecessary to keep the size in a cool place, the addition of borax being a sufficient protection against spoiling. But in spite of it all, in winter-time when in drawing the colors the fig-like formation should occur, it is advisable to return the size to the pot and to warm it up slightly so that the seasoned particles are dissolved, until an equal temperature is reached, whereupon after the lapse of one hour the marbling can again be proceeded with.
Should the size be too thick the trouble can be remedied by the addition of some warm water.
The quantity of mucilage contained in carrageen moss varies greatly, and the consistency of the size often depends upon the quality of the moss. The quantity which I gave as essential to the preparation of the size means first class moss.
Should the consistency of the size be insufficient after the first trial then from 1/2 to 1 ounce of moss should be added as it is clear that the carrageen moss is not of prime quality. Before I speak of another variety of size, I will repeat the main condition which should meet with the attention of every layman and which are as follows; the size must not boil too long, in order that it may not become flaky and muddy, it should remain for cooling in the same room in which the marbling is carried on, so that the temperature of of it and the air are the same; the colors should be prepared separately on a small quantity of size so that the whole size cannot become soiled and, lastly, the top of the size should be taken off before the colors are thrown on, so that no film can form before the colors cover the surface of the size.
The quicker the manipulation of marbling is executed the prettier are the edges produced. As soon as the size is covered with color, the formation of the film is prevented.
As the size is one of the most important parts in the process of marbling, I recommend these main points to the special consideration of the reader.
GUM TRAGACANTH.
GUM TRAGACANTH.
Gum tragacanth, also called gum-dragon, is the product of various species of astragalus which is found in Greece and Turkey and is a natural exudation of shrubs and from exudations resulting from incisions made in the stem near the root. This shrub is from 28 to 35 inches high and two inches in diameter. It is collected in July and August after the exudations have ceased. It is a hard, tough substance more or less white according to its purity in very irregular flattened shapes and in tortuous vermicular filaments. It contains aside from a little gum and starch, a consistent plant-mucilage without smell or taste and it is used in technical ways, in printing of textile fabrics and finishing, in producing plastic masses, as a binding medium for the production of confections and in the book-bindery for marbling size.
The leaf tragacanth of Smyrna is the best. It is brought to the markets of the world via Constantinople or via Smyrna in boxes of 100 to 200 lbs.
It forms flat ribbon-like pieces which consist of peculiar layers of horn-like consistency, white and diaphanous; when broken it is dull and splintered.
An inferior quality is the tragacanth of Morea, which generally comes from Greece via Trieste. This consists of oddly shaped, peculiarly twisted pieces, partly of pure white, partly of yellowish and brownish colors. For a long while, tragacanth was known as a good material for marbling size and, for that reason, it is used to-day in a good many of our book-binderies for this purpose.
It is much more liked than carrageen moss because the consistency of its mucilage and its durability are great and the preparation of the colors does not demand such great attention. But since my experiments and investigations upon the excellent effects of borax on the durability of carrageen size have become known, tragacanth has lost much of its popularity, because with it the edges can never be produced in a similar fine way as with carrageen size and besides the price is higher. Tragacanth is one of these short-viscous plant mucilages which swell in cold water but do not give a perfectly homogeneous solution. The mucilage consists of innumerable small granules, in which the starch is enclosed by cells.
These small granules prohibit, within the first two or three days of a fresh tragacanth size, the drawing of edges, as they make the colors thrown on appear rugged, and in drawing injure the fine hair lines. Five or six days after the dissolving of the tragacanth, the mucilage becomes more homogeneous and therefore better adapted for marbling.
If the swelled up mucilage is boiled, after the first or second day, then the solution will become perfectly homogeneous and will be as good as carrageen size except that the colors, which normally spread out on carrageen size, will expand much more on tragacanth size as it possesses more consistency and therefore they will become paler. The more dense the size, the thicker colors and the less gall is necessary to produce a normal expansion. The same difference in the power of expansion of the colors as in carrageen and the tragacanth is noticed in colors which normally spread out on tragacanth but which, very largely, expand on the size of plantago-psyllium (flea-bane) because the latter has the most consistency and homogeneity of them all. The different effects of the varieties of size on the colors are due to the consistency and to the different conditions of gravity. The objections of the consumers of my marbling colors who use tragacanth, are, that they consider the edges too pale. The cause of this is that my products are only prepared for carrageen size, inasmuch as my investigations have shown that it is the best, the cheapest and the most adapted for all varieties of edges.
The homogeneousness of the tragacanth mucilage in cold solution comes naturally after the size is five or six days old, because within this time fermentation of lactic acid occurs, which opens the cells of the small granules of starch while at the same time boiling heat has an immediate result in the same direction.
As soon as these cells are opened the formation of acids of the sugary parts and the fermentation of lactic acid of the starch contained in the size take place as fast as in any other variety of size, hence the size of tragacanth has no superiority over any other, besides the best, or picked-leaf tragacanth of Smyrna costs about four times the price of the best Carrageen.
For the preparation of the size, take 3 ounces of tragacanth, pour two quarts of water over it, leave it stand for 24 hours, then stir well and leave it standing for 12 hours more, repeat this until the homogeneous thick mucilage has been produced, then add 4 quarts of water, again stir it up well and filter it and the size is ready for the marbling process.
For tragacanth size, colors of great consistency, mostly fine earth colors are the best. They must be ground exceedingly well and very little ox-gall is to be added. But as these earth colors lack in the power to spread out and in divisibility, a characteristic of colors prepared for carrageen size, and as they never will have such fineness and smoothness, always appearing rugged, it is impossible for me to recommend gum tragacanth for the preparation of size.
I must mention further an effect, which earth colors exert on tragacanth size, viz., that they can be used on paper not prepared with alum, without running, while this is not the case with colors, which were prepared for the Carrageen size. In another chapter upon ox-gall I shall explain why the colors used with Carrageen size must be transferred on alum paper.
Salep, Plantago-Psyllium.
SALEP, PLANTAGO-PSYLLIUM (Flea-bane) AND THE OTHER GELATINOUS BODIES.
Radix salep are called the dried tubers of several species of orchids, they are round, quite flat, yellowish white, horn-like, semi-diaphanous, very hard and without taste or smell. Formerly salep was imported mostly from Persia, but now the tubers of orchids grown at home are collected and do not in any way differ from those coming from Asia. They contain a good quantity of gum and on that account are used for finishing silks and for medicinal purposes. It is sold ground, or as powder and can be bought at every drug-store. As marbling size, salep possesses very excellent properties, similar to carrageen moss, but its high price prohibits its general application. In preparing size, use, to 6 quarts of water 2-1/2 ounces of powdered salep which must be well boiled for a long period so that it may become entirely dissolved. After standing 24 hours, it can be used in the same way, as carrageen size.
Plantago-Psyllium (Flea-bane, Flohsamen, Flohkrautsamen) is the seed of different species of Way Bread belonging to the family of the plantaginea viz., plantago-psyllium, Pl-Arenaria, Pl-Cynops, the second of which is found in Eastern Germany, Switzerland, Hungary, etc. on sandy fields, the other two on the sea-shores of southern Europe.
The seed is small with one side flat and the other concave and has a furrow upon which is located the eye or navel. It is lustrous and of a reddish brown color, the best varieties coming from southern France. In consequence of the great quantity of plant-mucilage or gum, that it contains, by treating with hot water a consistent mucilage or size is obtained and used in the manufacture of marbled paper and for finishing textile fabrics.