Columbia Encyclopedia

(Encyclopedia) litmus, organic dye usually used in the laboratory as an indicator of acidity or alkalinity (see acids and bases). Naturally pink in color, it turns blue in alkali solutions and red in acids. Commonly...

(Encyclopedia) Millin, Sarah Gertrude (Liebson), 1889–1968, South African writer. The first of her novels about colonial and racial problems in South Africa is Dark River (1920). Later novels include God's Stepchi...

(Encyclopedia) laburnum ləbûrˈnəm [key] or golden chain, small tree (Laburnum anagyroides) of the family Leguminosae (pulse family) with decorative dark green leaves and sprays of bright yellow flowers. It is na...

(Encyclopedia) Azawakh, breed of long-legged, swift hound from the Sahel region of West Africa, particularly Burkino Faso, Mali, and Niger. Slim and elegant with a narrow, chiseled head, it stands from 23 to 29 in. ...

(Encyclopedia) Piranesi, Giovanni Battista jōvänˈnē bät-tēˈstä pēränāˈzē [key], 1720–78, Italian etcher and architect. The greater part of his life was spent in Rome, where he made etchings of the bui...

(Encyclopedia) alizarin əlĭzˈərĭn [key], or 1,2-dihydroxyanthraquinone, mordant vegetable dye obtained originally from the root of the madder plant (Rubia tinctorum), in which it occurs as a glucoside. The term...

(Encyclopedia) dodo, a flightless forest-dwelling bird of Mauritius, extinct since the late 17th cent. The dodo was closely related to the Rodrigues solitaire, extinct flightless giant found on another island in the...

(Encyclopedia) cameo kămˈēō [key], small relief carving, usually on striated precious or semiprecious stones or on shell. The design, often a portrait head, is commonly cut in the light-colored vein, and the dar...

(Encyclopedia) albedo ălbēˈdō [key], reflectivity of the surface of a planet, moon, asteroid, or other celestial body that does not shine by its own light. Albedo is measured as the fraction of incident light th...

(Encyclopedia) silicon carbide, chemical compound, SiC, that forms extremely hard, dark, iridescent crystals that are insoluble in water and other common solvents. Widely used as an abrasive, it is marketed under su...