Painting on Porcelain and Earthenware.

Manufacturer and Builder 6, 1876


THE decoration of porcelain and earthenware is certainly one of the most pleasant and, in a certain respect, easiest application of the art of painting. It combines indeed with the beauty and purity of the material, a richness of color and brilliancy of the enamelled glazing; and if from the nature of this branch of art, the execution has imperfections or is incomplete, it is compensated for by the infinite resources which it offers to the true artist — resources of such a nature that no other style of painting can afford.

As in all the decorative arts a correct and chaste design most be the base of a good execution, next to this good taste and imagination must assist, and show to the artist the best way and most advantageous disposition to embellish the piece to be ornamented, according to its form and purposes.

It is of course of the first importance to know the composition and nature of the different kinds of porcelain and earthenware, because the processes and the materials employed differ in various cases, notwithstanding the colors are always metallic oxide mixed with a larger or smaller quantity of the flux. We will explain the distinctive characteristics of the various kinds of porcelain and earthenware when treating of the different methods of painting them, but will first say a few words in regard to the general outfit and tools required by the porcelain painter, the same tools being used both for porcelain and earthenware.

The first requisite is a room with a table before a window with a northern exposure. The lower panes most be ground or covered with a transparent white paint, or white paper, to the bight of the eye. The table must be firm and solidly constructed and furnished with drawers, intended to preserve the brushes, colors, palettes, and grinding plates against dust and moisture. We would advise the fastening to the right side of the table a board with hinges, which can be raised and lowered as required; it is best to have this board about 2 feet long by 6 inches wide; when raised it must make a right angle with the front of the table, and is intended
to rest the arm and band on in case delicate work is to be done, for which a fixed and solid support of the whole forearm, from hand to elbow, is necessary to sesure a perfect freedom of motion of the fingers, and consequently a good execution.

The brushes are of different forms and sizes, and are either bristle or sable brushes; they must be carefully chosen, and it is very essential to keep them always in a very clean condition. Besides a certain number of the ordinary brushes, there are some kinds exclusively made for painting on porcelain, and which it is necessary to procure such are the blenders, intended to unite the tints and equalize the ground on which the design is drawn. The blenders must be very regular, the hair very equal, not too long, and above all so closely and carefully bound that no hairs can get loose from the brush. They are either flat, rectangular, round like the spout of a watering-pot, or, more commonly of a peculiar form, to which we will again refer further on; they serve to equalize the tints on concave surfaces, in the hollow of the moldings of vases, etc. Blenders of various sizes are also required. We ought also to mention a kind of flat and very long brush, serving to draw the lines in color or gold which adorn dinner-plates, vases, etc.

The colors, of which the number varies more or less, according to the style of painting which has been adopted by the artist, are usually sold in the pulverized form; they are best preserved in widemouth bottles, carefully corked and labelled, and they must particularly be kept protected against all moisture.

It is necessary to have a tin box, containing a porcelain palette full of more or less shallow cups, and into which cups the various colors are placed after they have been rubbed up with the flux. In the stores where artists' materials are sold in large cities, very well arranged boxes are found, of which we give a representation in Fig 2. They contain, besides the palette mentioned, a slab of ground plate-glass, large enough to grind small quantities of color. It is however also well to have a much larger piece of heavy plate-glass of the kind called double glass, also a number of heavy glass squares, on the back of which a white paper is pasted; these squares are useful to place the colors on, which are at once to be used after being ground, and they serve, if necessary, as a palette in work requiring the use of many colors, and of their mixtures.

The grinders, one of which is seen in Fig. 2, are of glass, well ground off flat, while they vary in size, according to the quantity of color to be ground up; two or three however are sufficient. We can not too strongly recommend that the glass plates and grinders be kept in a condition of scrupulous purity, and to clean them well with alcohol every time after they have been used; in fact the least trace of an iron color is sufficient to ruin in the most distressing manner the clear colors, especially carmines, when afterward ground with the same tools.

In order to mix the colors after they have been ground, they are removed from the glass plate by means of the palette knife, which is a kind of steel knife, very thin, flexible, and elastic; the ends of these knives should be in the form of an elongated triangle, which is preferable to all other forms; for colors which may be affected by iron, such as the clear yellows, carmines, etc., a palette knife should be used made of horn or ivory, and not of steel, but of the same shape.

The liquids used for mixing the colors are rectified spirits of turpentine and thick turpentine, essence of lavender, or of oil of aspic, common and thick; these, with alcohol used for cleaning the brushes, grindingtools, and palette, are all that is required for the preparation of the colors used in all branches of the art of porcelain painting. All these substances are found in commerce; the thick oil of turpentine however is better when prepared by the artist. In order to do this, common oil of turpentine is poured into several small cups, such as are used for India-ink, and these are placed on a plate under a glass bell-jar to protect them from dust; the edge of the glass is raised about an inch, to give access to the air as exit to vapors arising. This is then placed in the sun, or in winter in a warm room; the essence evaporating leaves at the bottom of the cups a thick substance of about the consistency of honey; this is the material wanted. In this way it is obtained in a form far superior to the thick turpentine of commerce. The thick essence of lavender is obtained in the same way.

In order to use these essences more easily, it is well to place them in ordinary glass bottles with a medium sized neck, closed with perforated India-rubber stoppers, through which a glass tube passes, drawn out to a narrow point, no that the essence will flow out drop by drop. Formerly corks were used through which a quill passed, but these are attacked, especially the corks, by the turpentine, no that they have often to be renewed, therefore those artists who are informed in regard to modern improvements in chemical tools, have discarded the corks and goosequills and substituted rubber and glass. Fig. 3 represents a bottle of this kind for the ordinary essences; for those which are thick a widemouth bottle is taken, (Fig. 4,) to the stopper of which a little stick is attached, the lower end of which almost touches the bottom of the bottle. The quantity of fluid which adheres to the stick when the stopper is removed is sufficient for all ordinary purposes, as in any case only small quantities of these essences are required.

It often happens, especially with beginners, that the color, badly prepared or badly employed, conglomerates in thick drops, which, at the baking of the porcelain, produces air bubbles or scales; in order to avoid such defects, it is well to have very sharp scrapers with points either round or like a lancet, used to make the too great thickness thinner, and also to remove particles of dust, which are always found to be deposited on the objects notwithstanding every possible precaution used. Short needles fastened in wooden handles are also used, and serve to perforate the designs and perform operations to be described in a future number.

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