After the ware has been fired once and is in what is called the “biscuit,” it can be decorated by the use of underglaze colors, in the form of thin washes resembling water-color painting. Ware used for this purpose should be made of white, or very light cream-colored clay, as the colors, being used in transparent washes, would be dimmed, and would have their tints sullied by use upon a ground of dark color.
On white ware those colors should be used which will best stand the heat necessary in the firing and glazing of this ware. For this reason painting executed on white is usually in monochrome, and only the strongest colors are used, such as blue, black, or brown. The best effect is produced by the use of blue. This style of work is familiar from the numerous pieces of Japanese ware, of porcelain or white earthen-ware, painted in blue, which are brought to this country.
The method of painting is simple and not likely to prove difficult or uncertain as to its results in the hands of one familiar with the use of water colors. The color generally used is dark blue, and there are several different blues which furnish very fine tints. Among these might be mentioned Emery’s cobalt blue, which is excellent and does very well upon the white ware manufactured here. Phillips’ mazarine blue and Harrison’s Persian blue are also very rich, deep colors, the latter having a purplish tint. One of the best blues, as reliable and pleasing in color as any, has been prepared by Mr. Joseph Bailey, of the Hamilton Road Pottery.
The color must be rubbed down until perfectly smooth, and should be mixed with water and enough gum arabic to keep it from rubbing off in the necessary handling before firing. The design having been sketched upon the ware to be decorated, with a lead pencil, the first washes may be put in with a light tint of the blue. These should be laid on with a free hand and without retouching before they have dried. The darker tints may then be laid in, and lastly the deepest shadows. These should be painted thickly and sharply to give the proper depth of color. If necessary they may be painted over a second time; care should be taken, however, not to have an excess of paint in any part, as that would prevent the glaze from adhering to the ware. The lines should be particularly clear and sharp, as they generally spread more or less in the glazing, and if they are not well defined and the shadows are not dark enough, the effect will be blurred and indistinct. In this kind of work clearness and distinctness are to be desired. If the painting is carefully executed and the various degrees of light and shade are well preserved, something of the effect of a painting in water colors will be produced. Monochromes in brown and black are done in the same way, only that in the case of the latter color it is better to mix a very little blue with it, as that will make it stand the fire better. Before glazing, the ware should be fired once to “harden on” the colors. If the color should run in the glazing, the painting may be repaired by the use of gilding over the glaze, by which the blurred outlines may be concealed. When, from the perfection of the firing, this is unnecessary, work of this kind, and especially that in blue, may be very much enhanced by a judicious use of gilding.
This is done upon a very light, cream-colored ware. The method of painting is similar to that described above, with the exception that all colors can be used. In using the weaker colors, and in mixtures, the same rules that have been given before must be observed. Colors which do not stand the fire very well, such as yellow and rose color, must be laid on thickly, while in mixtures, as well as when used alone, the stronger colors should be used sparingly. In the Lambeth or Bennett style of painting upon faience, the designs are either wholly or partly conventional. The grounds are either left the natural color of the ware or painted. The designs usually of flowers are in natural colors very slightly shaded and surrounded by a dark outline.
The design having been drawn upon the surface with a lead pencil, the ground, if it is to be colored, may be laid on with some color, or mixture of colors, which will harmonize with the decoration. As it is impossible to paint it smoothly with a brush, or to do it by any of the methods in use for over-glaze painting, the ground must be “dabbled” on, either with a small blending brush, or better, a sponge, which has been cut to the proper shape and size, and which may be fastened in a quill and used as a brush. This is dipped in the color which has been mixed upon the palette, and with it the color is applied to the surface of the vase, producing a mottled ground, which may be shaded from light to dark, by the application of more or less color, as desired, and also may be varied by the introduction of other colors which will harmonize with each other, and with the decoration. The design may then be painted in flat washes, which should be laid on freely, with the shadows boldly defined. This done, a line, either of black or dark olive green, made from dark brown and a little green, may be painted around the design, outlining and relieving it against the ground.
The painting finished, the piece should then be fired to fix the colors. If necessary, it can be touched up in any places which are thought to need deeper tints after this firing, and before the final process of glazing. It must be remembered, however, that the effect of the glazing will be to deepen the colors, and, unless the result of this process has been learned from experience, the tendency will rather be to get them too dark than too light. The most important thing is, to keep the relative value of the lights and shadows. If this is done, the effect will not be bad, even if the colors should fade a little in firing.
Another very important item in under-glaze painting, which has been mentioned before, is, that the colors must be in proper condition for use, and to that end, must be carefully rubbed down with a muller or palette knife. Inattention to this detail has caused much work of rude and rough appearance to be produced, which might otherwise have been fairly good.
In the Lambeth and Bennett ware the charming effect of color will generally be found to have been produced by a system of burning which would scarcely be considered legitimate, according to the strict rules of the potter’s art. The ware is not fired in the biscuit as hard as such ware is usually fired, and the glaze applied is softer than the body of the ware demands. This soft glaze is used to save the colors, and not being suited to the body of the ware will, generally, be found to be badly crazed. In this case, however, lovers of beautiful and harmonious colors, in the decoration of pottery, will think that the ends justifies the means, and as the articles are wholly adapted for ornamental purposes, this defect of glaze detracts but little from their value.
Some work of a similar character has recently been done in this city, however, in which the ware has been fired and glazed in such a manner as to make it perfectly durable, and, at the same time, great beauty of coloring has been retained. This result is not only important from the fact that it offers opportunity for the production of ornamental wares, but, also, from the consideration that the perfection of the firing and glazing of the ware renders it valuable for articles of use. Nothing could be prettier than sets of tableware made of this cream-tinted clay, decorated in colored, conventional designs. This would, we think, be the perfection of ware for ordinary use, and would form, with the combination of the delicately tinted body and the harmonious colors of the underglaze decoration, a service both pleasing to the eye and very durable.
It is not the province of a work on under-glaze painting to enter into the subject of over-glaze decoration, yet as they are frequently combined, mention may be made of some of the varieties of decoration in which the two processes are used. The most common form of the union of the two methods is that in which gilding is used as an adjunct to under-glaze decoration. Gold is always applied over the glaze, as it would be utterly destroyed by the action of the heat necessary in the firing of any hard glaze. That prepared by decorators by dissolving gold in aqua regia may be used, or the “bright” gold, which is obtained in a liquid state. The former is the most durable, and when fired can be burnished or left with a dead finish, which in many cases has the most pleasing effect. The “bright” gold, as its name indicates, becomes bright in the firing and the burnishing is thus rendered unnecessary. On a “smear” glaze the “bright” gold produces a beautiful dead gold effect, owing to the dead surface of the ware to which it is applied. In Japanese wares, dark blue, under-glaze, often appears in conjunction with gold, and also with red, green, or other colors which have been put on over the glaze.
One beautiful result of the combination of over and under-glaze painting is seen in the ware painted by Lemonnier. In this the ground is generally painted under the glaze in a manner similar to that described in this chapter for the production of Lambeth faience. The design is then painted with over-glaze “relief” colors, and the high lights laid in heavily, the whole producing an effect which combines the delicacy of the over-glaze colors with the depth of the under-glaze.
We have tried to indicate, in the preceding chapters, the principal methods employed in the decoration of pottery under the glaze. These various methods are combined with each other and with over-glaze work in so many ways that it is difficult for any but an expert to distinguish in a given piece of ware the many processes which may have combined to produce the result. This renders the subject more difficult to treat comprehensively, and these various ramifications of the art of under-glaze painting can here be but indicated. It is hoped, however, that the suggestions given may be sufficient to afford the student of ceramic decoration an idea of the various forms and of the possibilities of the art.