PRIMARY COLORS.--See Colors, primary.
PURE COLOR.--A color produced by h.o.m.ogeneous light. Any very brilliant or decided color.
PURPLE.--A color formed by the mixture of blue and red, including the violet of the spectrum above wave length 0.417, which is nearly a violet blue, and extending to, but not including, crimson.
RAINBOW.--A bow or an arc of a circle, consisting of the prismatic colors, formed by the refraction and the reflection of rays of light from drops of rain or vapor, appearing in the part of the heavens opposite to the sun.
RED.--A color more or less resembling that of blood, or the lower end of the spectrum. Red is one of the most general color names, and embraces colors ranging in hue from aniline to scarlet iodide of mercury and red lead. A red yellower than vermilion is called scarlet. One much more crimson is called crimson red. A very dark red, if pure or crimson, is called maroon; if brownish, chestnut or chocolate. A pale red--that is, one of low CHROMA and high LUMINOSITY--is called a pink, ranging from rose pink or pale crimson to salmon pink or pale scarlet.
VENETIAN RED.--An important pigment used by artists, somewhat darker than brick red in color, and very permanent.
RETINA.--The innermost and chiefly nervous coat of the posterior part of the eyeball.
SATURATION, OF COLORS.--In optics the degree of admixture with white, the saturation diminishing as the amount of white is increased. In other words, the highest degree of saturation belongs to a given color when in the state of greatest purity.
SCALE.--A graded system, by reference to which the degree, intensity, or quality of a sense perception may be estimated.
SHADE.--Degree or gradation of defective luminosity in a color, often used vaguely from the fact that paleness, or high luminosity, combined with defective CHROMA, is confounded with high luminosity by itself. See Color, Hue, and Tint.
SPECTRUM.--In physics the continuous band of light showing the successive prismatic colors, or the isolated lines or bands of color, observed when the radiation from such a source as the sun or an ignited vapor in a gas flame is viewed after having been pa.s.sed through a prism (prismatic spectrum) or reflected from a diffraction grating (diffraction or interference spectrum). See Rainbow.
TINT.--A variety of color; especially and properly, a luminous variety of low CHROMA; also, abstractly, the respect in which a color may be raised by more or less admixture of white, which at once increases the luminosity and diminishes the CHROMA.
TONE.--A sound having definiteness and continuity enough so that its pitch, force, and quality may be readily estimated by the ear. Musical sound opposed to noise. The prevailing effect of a color.
ULTRAMARINE.--A beautiful natural blue pigment, obtained from the mineral lapis-lazuli.
+VALUE.--In painting and the allied arts, relation of one object, part, or atmospheric plane of a picture to the others, with reference to light and shade, the idea of HUE being abstracted.+
VERMILION.--The red sulphate of mercury.
VIOLET.--A general cla.s.s of colors, of which the violet flower is a highly chromatic example. The sensation is produced by a pure blue whose CHROMA has been diminished while its LUMINOSITY has been increased. Thus blue and violet are the same color, though the sensations are different.
A mere increase of illumination may cause a violet blue to appear violet, with a diminution of apparent CHROMA. This color, called violet or blue according to the quality of the sensation it excites, is one of the three fundamental colors of Young"s theory. A deep blue tinged with red.
VIRIDIAN.--Same as Veronese green.
WHITE.--A color transmitting, and so reflecting to the eye, all the rays of the spectrum, combined in the same proportion as in the impinging light.
YELLOW.--The color of gold and of light, of wave length 0.581 micron.
The name is restricted to highly chromatic and luminous colors. When reduced in CHROMA, it becomes buff; when reduced in LUMINOSITY, a cool brown. See Brown.
VERONESE GREEN.--A pigment consisting of hydrated chromium sesquioxide.
It is a clear bluish green of great permanency. Also called Viridian.