Scientific American 40, 26.6.1847
(Continued from No. 39.)
PAINTING iN OPAQUE WATER COLORS.
It was intimated in the commencement of this series, that no inconsiderable part of the art of painting, consisted in that or ornamental and fancy painting in water colors, or what is by way of distinction termed kalsamine painting. The most elegant scenery, the most splendid panoramas, and brilliant landscapes, are produced with colors ground and mixed with water, and tempered with glue, alum or isinglass, to harden and render them permanent. The usual proportion of ingredients used in the preparation of menstruum for this work, is one pound of fine white glue, and two ounces of alum to two gallons of water. For more delicate work, and where the smell of the glue would be objectionable, gum arabic, or even rice glue, may be substituted. The alum may be dispensed with, but its oresence tends to secure the work agains injury by water. Nearly all the different colors and pigments used in oil painting, with the exception of white and red lead, are also used in this branch, besides a great variety of other bright and brilliant colors, prepared expressly for this kind of painting, Spanish white, commonly called whiting, and Paris white, constituting the bases of most of the light tints. The tools used, consist of all the variety of brushes and hair pencils, that are used in oil painting, besides various large and flat brushes peculiar to water painting, and not used in oil. in theatrical scenery painting, which is principally executed on canvas, the cloth must be first sized with thin paste, and dried, before the colors are applied; but in painting on plastered walls, no preparation is necessary; and this paint being in general much more perfectly opaque than oil paints, only one coat is required to produce a full opaque and uniform body. The colors are first mixed with water, to the consistence of masons' mortar, before the glue sizing is added; they are then diluted with the sizing to a convenient consistence for working freely. in the progress of the work when colors become too thick or stiff by evaporation, they must be diluted with water instead of the sizing; otherwise they will become so strongly tempered with glue, as to be in danger of cracking at the surface in the course of time, if not immediately. These colors when once mixed with the sizing, cannot be preserved but a few days at most; wheretore it is better to keep the paints on hand, ready ground in water, and temper them in small quantities only, as they are wanted for use. The whites require no grinding; neither do Venitian red nor yellow och re - Lampblack, which is the principal black used, requires to be first mixed with rum, or other spirits, and water, in equal quantities, and ground perfectly fine, before being used. The principal colors peculiar to this branch, are slip blue, celestial blue, blue verditer, green verditer, rose pink, and Chinese yellow; these require no grinding. All these colors change several shades, some more and some less, in drying, and it is one of the principal points in the arts of water painting, to judge the extent of this change, so as to prepare and apply such colors and shades as will appear as intended, when dry.
LANDSCAPE PAINTING ON WALLS OF ROOMS.
The kind of painting having been thoroughly proved to be cheaper and more durable as well as more elegant than paper hangings, there appears no other good reason than the want of competent artists to execute such work, to prevent its coming into general use, in preference. A convenient apparatus for this branch is easily obtained, and the expense thereof is comparativelytrifling. About twenty different colors most of them in small quantities, the same number of small tincups and a dozen common paint brushes of different sizes, constitute the principal requisite preparation. There are a variety of compound colors required in the process, which will be described progressively. The first part of the process after having prepared the colors as directed in our last number is to examine the walls, and fill up all the cracks and holes with a putty made made of whiting (Spanish white) mixed in glue sizing. This is best performed with a piece of wood in the form of a chisel, and inch or more in width. Then draw a line with a lead pencil or flat piece of lead, round the room, on a line with the bottom of the windows, and another about five feet from the floor, if the room is high; otherwise this line may be lower; the first is termed the dadoe line, and the latter, the horizon line; it being intended to represent the height at which the surface of the ocean would appear, if represented in the painting. The observation of this line is very important, as it serves as a guide in locating the distances, and various objects therein. Make skyblue by adding celestial blue to whiting till the color appears about two shades deeper than it is intended when dry. Also make a horizon red by mixing together ten parts in bulk of whiting with two of orange red and one of chrome yellow. Then make a cloud color, by mixing an indefinite small quantity of horizon red with whiting. Every compound color should be mixed before veing diluted with the glue sizing.) The sky-blue may be applied by a large common paint brush, either new or worn; but a brush for the application of the cloud color should be large and short. A half-worn brush is best, but if this cannot be obtained, a new brush may be wound with twine so as to reduce the length of the brush part and will answer the purpose. Paint the upper part of the walls from the top to the vicinity of the horizon line with sky-blue, but leaving a space from six to ten inches above that line, which must be at the same time painted with the cloud color, and these two colors must be blended together by brushing vertically till the cloud color gradually disappears in blue. Also immediately, and before the blue is dry, a variety of rising clouds may be formed by striking the cloud brush, charged with cloud color, endwise, or nearly so, but with the handle inclining such curves and pillar forms as rising clouds present. Floating clouds may be also represented high upon the walls, by a similar process, and painitng the lower edge of the clouds with a light slate color (a mixure of black, slip blue and white) slightly tinged with venetian red, or pink. We shall present an engraving, in illustration of this subject in our next.
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