HOUSE DECORATION - DIFFERENCE BETWEEN COLOR AND PAINTS In interior work, paint is employed chiefly for decorative and ornamental purposes; and these we shall now consider in detail.
It is necessary that the student and worker in paints should clearly understand the differ ence between the two terms pigment and color, oftentimes confounded. Color is but a sensation aroused in the mind or consciousness through the action of light upon the nerve-fibers of the retina. Pigments, on the other hand, are sub stances which, when acted upon by light, absorb certain of the rays of color therein contained, and, by either reflection or transmission, give forth that particular color by which they are known. It will readily be understood that the distinction between color and pigment is not in any way a distinction of terms only.
The house-painter, however, deals with pig ments, color being the resultant effect. The term pigment, as already mentioned, implies the sub stances or materials that are laid upon surfaces to impart color; and the laws that govern the mixing of pigments are not identical with those that control the blending of colors. For instance, the addition of yellow pigment to blue will result in a mixture having a green hue; although the union of blue and yellow colors will result in white.
It will be well at the commencement of this chapter to state briefly the meaning of the prin cipal technical terms used in the text, so that the subject may be plain to the reader's understand ing.
Pigment is any coloring substance or mate rial from which a dye, a paint, or the like may be prepared; the term is applied particularly to the refined and purified coloring matter ready for mixing with an appropriate vehicle.
Oil-color is a paint made by grinding a color ing substance in oil; the term is applied to such paints taken in a general sense.
Vehicle is any liquid with which a pigment is applied, including whatever gum, wax, or gluti nous or adhesive substance is combined with it. Water is used in fresco and in water-color paint ing, the colors being consolidated with gum-ara bic; size is used in distemper painting. In oil
painting, the fixed oils of linseed, nut, and poppy are used; in encaustic, wax is the vehicle.
Driers consist of drying oil, a substance min gled with the oil used in oil painting to make it dry quickly.
Oil of turpentine, or spirit of turpentine, is a colorless oily hydrocarbon, of a pleasant aro matic odor, obtained by the distillation of crude turpentine, which is an exudation of the tere binth, or turpentine-tree.
Varnish is a viscid liquid, consisting of a so lution of resinous matter in an oil or a volatile liquid, laid on work with a brush or otherwise. When applied, the varnish soon dries, either by evaporation or by chemical action; and the resin ous part forms thus a smooth, hard surface with a beautiful gloss, capable of resisting to a greater or less degree the influence of air and moisture. According to the sorts of solvents employed, the ordinary kinds of varnish are divided into three classes—spirit, turpentine, and oil varnishes.
Tempera is a mode or process of painting; the term is applied especially to early Italian painting, the common vehicles of which were yolk of egg, yolk and white of egg mixed to gether, the white juice of the fig-tree, and the like. Distemper is a preparation of opaque or body color, in which the pigments are tempered or diluted with weak glue or size (if tempera) instead of oil, usually for scene painting or for walls and ceilings of rooms.
It may be well here also to define some of the terms that are frequently used in treating of color. The principal quality of a color is its hue. It is this that first appeals to the sight, and by which we are able to name the color; and we speak of it as "red of an orange hue," or "green of a bluish hue," and so on.
Pure color is absolutely free from any admix ture of white. Brightness, or luminosity, is a term that has reference to the amount of light the color reflects to the eye. These three quali ties—hue, purity, and brightness, or luminosity —are termed the constants of color.