PAINTING. 525 



said to be relieved, or in relief. When objects are seen at a dis- 

 tance, the intervening air makes the light parts seem darker, and the 

 dark parts lighter, than if they were near ; thus reducing them more 

 nearly to one uniform shade. This effect, which causes distant 

 mountains, or the ocean, to blend, almost, with the sky, is called 

 aerial perspective. Shading may be executed with a pen, pencil, 

 crayon, or brush ; and by means of lines, or dots, 01 a continuous 

 mass of color, as in drawings washed with Indian ink. 



3. The art of Coloring, consists in representing the various 

 colors of the objects in a picture; of course, in connection with 

 drawing and shading. The theory of colors has already been 

 noticed under the head of Optics ; (p. 359) ; but we must here add, 

 that the colors of individual objects are greatly modified by the light 

 reflected from other objects which surround them. Thus, a person 

 sitting by the side of crimson drapery, would receive a red tinge 

 therefrom, distinct from his natural color ; and still more so from 

 what he would receive, were the drapery of a gloomy hue. The 

 brilliant parts of a picture, are painted by diluting the natural color 

 with white : but the dark parts require a mixture of some darker 

 pigment, harmonizing with the natural color ; which last is found only 

 in the middle tints. If the colors of a picture are generally bright, 

 with feeble shades, they give it a light tone ; but darker colors pro- 

 duce a deeper tone ; and any one color predominating, gives its own 

 tone to the picture. In portrait painting, much depends on the 

 proper choice of the back ground, or part surrounding the principal 

 figure ; which should generally be of a neutral or mixed tint, rather 

 than of a decided color. 



Water colors, are finely ground, and mixed with gum arabic, to 

 give them consistency and cohesion ; but oil colors are mixed with 

 linseed or other vegetable oil, which has been previously boiled, 

 to render it siccative, or capable of drying speedily. Vermilion, 

 chrome red, Indian red, carmine lake, madder lake, burnt sienna, raw 

 sienna, (terra di sienna), chrome yellow, gamboge, yellow ochre, 

 chrome green, Brunswick green, Prussian blue, ultramarine, indigo, 

 ivory black, Indian ink, umber, bistre, flake white, and zinc white, 

 are among the pigments used in coloring pictures ; most of them 

 being suitable either for water colours or oil. In distemper painting, 

 which was much practised before the use of oil, the colors are mixed 

 with glue, or size ; and in fresco painting, the colors, thus mixed, 

 are applied to freshly plastered walls, and imbibed by the plaster 

 before it becomes dry. Mosaic work, is executed with small blocks 

 of marble, glass, or other substance, attached to a proper ground ; 

 each block having the color of that part of the picture or design 

 which it contributes to form. 



4. Under the head of Pinacography, we propose to name a 

 few of the most remarkable paintings ; of which this would be the 

 place for a full description, in a more extensive work. The name is 

 suggested by the term pinacotheca, signifying a picture gallery, 

 derived from the Greek rftpal, a picture. It is a subject of regret, 

 that many of the finest paintings of the oldest masters are much 

 decayed ; and unless perpetuated by means of superior copies, their 



