This section is from the book "A Treatise On Architecture And Building Construction Vol4: Plumbing And Gas-Fitting, Heating And Ventilation, Painting And Decorating, Estimating And Calculating Quantities", by The Colliery Engineer Co. Also available from Amazon: A Treatise On Architecture And Building Construction.
149. Interior decoration may be executed in oil color water color, or tempera, commonly termed distemper the last named being a form of water color not ground' but simply stirred in water, and unlike the ordinary color ground in water, opaque instead of transparent. The character of the work to be executed very largely determines which of the above named media should be used, though excellent results are, from any of them, to be obtained.
150. Oil color possesses the greatest body, or consistency, and, so far as affected by the weather, is the most permanent. It is applied with brushes similar to those already described, but additional forms are desirable for particular uses. Decoration in oil color consists in the execution of a design upon walls or woodwork previously painted m body color, in the ordinary house-painter's work, which body color forms the background for the decorative design When large surfaces are to be covered with detail, or where the work is to be carried on, day after day, from the place where it left off the previous day, oil color is preferable, as the exact shades required can be mixed with the palette knife on the palette, and when dry on the wall will not change color.
In many places it is found necessary not to execute the work directly on the wall itself, but upon canvas, afterwards stretched over the walls and secured in place.
This is especially the case in what is known as tapestry painting, where descriptive pictures are executed upon various fabrics, afterwards hung or stretched over the panels formed in the side walls of the room by pilasters or moldings. For painting canvases, an easel is necessary to hold the frame with stretched canvas on which the work is executed. The easel, as shown in Fig. 47, consists of a ladder-like frame, with adjustable pegs on which the canvas frame rests at such a height as best suits the painter's convenience.
As oil paint dries with comparative slowness, the resting of the hand upon any part of the painted canvas during the progress of the work would leave a mark; the decorator in oil, therefore, provides himself with a mahlstick, such as shown in Fig. 48, with which he forms a bridge across the front of his easel on which to rest his hand. The mahlstick consists of a slender rod of wood, with a felt or chamois covered ball on one end, resting against the upper part of the easel or canvas, while the left hand holds the lower end of the mahlstick. The painter's right hand is then rested on the mahlstick while it plies the brush upon some particular part of the work. When the work is executed directly upon the wall surface, the mahlstick is still used, but the easel, of course, dispensed with. In order, however, to reach his work on the upper part of the side walls, or upon the ceiling, the painter must have a pair of trestles with which to form a platform, as shown in Fig. 49. The rungs, or steps, on these trestles admit of the building of a temporary platform at varying heights, to reach the work, in the same manner as the changing of the pegs in the easel permits the painter to raise or lower his canvas, so as to have the part he is working on directly in front of the eye.
151. Water-color painting may be executed upon the plastered wall surface-either smooth or sand finish-upon which no previous preparation is necessary, except a coat of thin size applied and permitted to dry so as to prevent the color from sinking too deeply. As water color is very transparent, it is necessary that the surface to which it is applied should be perfectly white, as the faintest suggestion of color will show through the paint and contaminate the applied tint. Besides this, there is no such pigment as white in water colors, and where the design calls for a white surface, it is desirable to leave the natural wall finish show. White pigments ground in water may be used in some places, but they belong more to distemper painting, hereafter explained, than to what is known as water-color work.
Water colors are not, like oil colors, mixed on the palette, but ground or mixed for use in saucers or cups, the proper tints being obtained by mixing one color with another, by means of a brush. The requisite depth of color is secured by grinding more or less of the pigments with a given quantity of water, or by going over the painted surface a second time to deepen the shade. The former method is, in most instances, preferable, though certain cases exist where a second painting is almost absolutely necessary. Water-color painting requires extreme care, as any error of color or drawing cannot be corrected after the color is laid-the previous work necessarily showing through. This is the strongest distinction between the methods of water-color and oil-color work, for, in oil color, the work may be changed as many times as the painter sees fit, either by working over the first coat when dry, or by wiping it off while wet. Oil color being opaque, does not, unless very thinly applied, show what may be under it. Water-color decoration is materially affected by dampness and by strong light, and should, therefore, be used only in such places as are dry and comparatively shaded. It admits of a delicacy of treatment, however, in no way attainable in either oil or distemper, and for certain styles of design is almost indispensable.
The brushes used in water-color painting are all of the softer grades, such as sable or camel's hair, as the color is very thin and spread over the surface very evenly, so as to leave no excess on any part, to deepen the shade of that part. The soft hair brushes readily absorb any superfluous color, while the hard bristle brushes do not. In applying a water-color tint, the brush is charged with all the color it will hold, and then passed rapidly over the surface, spreading the color as far as desired, then wiped dry on a rag or piece of blotting paper, and reapplied to the painted surface to remove any excess of color. Water color is always applied in washes or even tints, over which the design is executed in additional washes or more thickly ground color.
152. Tempera, or distemper, painting is similar to water color, inasmuch as the pigment is mixed with water as a vehicle, but is in other respects totally different. • The color is not dissolved in the vehicle, and its suspension is so uncertain that a slight addition of size or glue is necessary to hold it in place upon the painted surface, after the water has evaporated. The colors are all mixed to the shade required, and no amount of dilution will render them softer or more delicate, as is the case with water color. Dilution, however, depletes the effective proportion of size, rendering the color unstable and likely to drop from the surface in powder when the distemper is dry. In distemper painting, white is applied in the same manner as in oil painting, instead of leaving the wall surface to show through, as in water color. White is also mixed with the other pigments used, in order to lower their intensity and give the color body. Painting in tempera may be, in consequence, applied over other work in the same material, unless the first work is of such a dark color that it would be likely to show through. When tempera painting is used to cover an expanded surface with an even tint, it is usually termed calcimine, and as such, largely used on ceilings and some side walls. The same material, however, is often used to execute detailed designs in various colors, and, though not as brilliant as either water color or oil, has its place in certain schools of design.
Tempera painting is executed with brushes similar to those used for oil colors, with the addition of a few others of softer hair, similar to the water-color brushes. When used to do calcimining, a broad, flat brush is required to spread the color rapidly over a considerable surface, as the color dries quickly and is likely to show marks where the dried surface is overlapped by wet paint. It is, for this reason, desirable to mix up a considerable quantity of distemper at one time, as it is almost impossible to secure the exact shade required to finish a surface started on with an insufficient quantity of color ready mixed. The color, as first laid, is several shades darker than when dry, and to determine the finished tint, it is customary to apply a small amount of the color to some obscure part of the wall and let it dry before proceeding with the rest of the work. Then if the tint is not satisfactory, more pigment can be stirred into the solution until the desired color is attained.
153. To combine the advantages of the two modes of painting-oil and water color-many attempts have been made, either through successive processes, or the use of a vehicle of compound nature and intermediate affinity to both fluids, thence technically denominated a medium, a term properly applicable to every vehicle. It is well, in regard to media, to note that all the gelatinous substances, hereinbefore noted as additions to water vehicles, may be combined with linseed and other oils. The compounds thence resulting may be employed as vehicles and will keep their places as delivered by the brush in painting. Starch, as prepared by the laundress, has been, indeed, lately commended for this purpose. These mixtures are, however, both chemically and mechanically inferior to the combination of lac and borax, which, equally diffusible in water and oil, does not contract in drying nor render the painting penetrable by moisture, as do farinaceous and mucilaginous substances, nor yet, in the end, dispose the work to crack. Against the proposition that artists should adopt the Indian process of painting, in which lac is rendered saponaceous and miscible in water, through the medium of borax, the foul color and opacity of the vehicle have been justly advanced.
Dissolve, however, 1 part of borax in 12 of boiling water, adding the solution in due proportion to white lac varnish, the result being a transparent, colorless liquid diffusing freely in water, which may, but not without difficulty, be used instead of oil as a fast-drying vehicle for paint. When dry, it is not removable by water. This lac vehicle is, besides, as freely miscible with oil as it is with water, supplying that true medium or connecting link between painting in water and oil, which, in ingenious hands, unites the advantages of both.