The Progress of the Marbling Art, from Technical Scientific Principles / With a Supplement on the Decoration of Book Edges

by Josef Halfer

The size and the technical application of the colors demand great attention and practice; on the other hand, the preparation of colors but labor. The colors are divided into two groups, mineral and lake colors. In the lake colors, if they are good and strong, the coloring matter bound to the metallic oxides is equal to one-half of the whole weight of the color, therefore they can be prepared as good marbling colors without adding anything but gall. On the other hand, in mineral colors, which in a natural or chemical way are bound to bodies, the body weighs much more than the coloring substance and even if the metallic oxide is the real coloring substance, as is the case with ferric hydrate, the organic coloring matters derived from the vegetable or animal kingdom are preferable to the inorganic substances.

Why this is the case we shall see further on. In those coloring substances, which I have recommended as good marbling colors, the aggregate state of the body is amorphous and admits of the greatest divisibility. If such a coloring substance is ground in the finest way possible, the division of the body is a very great one, but an intimate union of the particles can never take place because first, the color is insoluble in water and, second, because the division (diminution) of a body has its limits. For this reason particles are isolated and lay loosely alongside of each other.

If a mineral color is mixed with the necessary amount of water and gall and thrown upon the size the drop expands to a round disc, which upon close investigation, is found to consist of numberless small dots. When such coloring stuffs are used, the union of the particles must be brought about by some glutinous matter. This is unnecessary with lake colors, where the coloring matter is as heavy as the body to which it is bound, as all organic substances possess a sufficient quantity of glutinous matter to form a union of the particles.

The clearest proof of the correctness of my allegations we find in a mineral color, in which the metallic oxide was precipitated by a semi organic salt, I mean French blue, which without any substance unites the particles quite well if the washing of the precipitate after the blueing, was a perfect one.

The glutinous matter used with mineral colors must be entirely free of any acids as the smallest particle of acid, which in warm weather is often formed after long standing causes an isolation of the coloring matter in such a way, that it will become curdled when thrown upon the size. The best glutinous matter, that can be used, is dissolved isinglass or parchment-glue with gum tragacanth. As the first two named materials are expensive they can be replaced by fine gum arabic free of acid. Take 4/6 of an ounce of gum tragacanth let it swell in 1 pint of water and dissolve fully by boiling. In this way we obtain a glutinous mass, which is mixed by stirring with a thick solution of gum-arabic. This mixture is used to unite the particles of the body of mineral colors.

To grind the colors use a very smooth marble slab, a roller and a palette knife, of wood or horn, as those of steel produce some change upon red colors.

The colors which are sold in the market are either in the form of grooved pieces, little cones, or powder. If the color is in pieces or little cones, it is first ground to powder in a dry state and is then mixed with a little water and from 10 to 15 drops of ox-gall to a thick paste. If a mineral color, add a piece of the glutinous matter the size of a nut, if, on the contrary, we have a lake color, the addition of water and gall is fully sufficient.

Now commences the grinding. With a muller you continually run in a circular motion over the color using a moderate pressure of the hands. After about two or three hours have elapsed the color will have the requisite fineness which is shown by its greasy, lacquer-lustrous appearance. During the grinding, move the color from time to time into the center of the marble with the palette knife and at the same time the adhering color is removed from the roller.

When the color is ground fine it must be diluted with water in a glass vessel and is then ready for use. Bottle tightly and keep it in a cool place, best in the cellar.

For grinding the colors and diluting the same, river or rain water should be used, of course, proportionately to the quantity of color so that the latter will not become too thin.