Columbia Encyclopedia

(Encyclopedia) feldspar fĕlˈspär [key], an abundant group of rock-forming minerals which constitute 60% of the earth's crust. Chemically the feldspars are silicates of aluminum, containing sodium, potassium, iron...

(Encyclopedia) stoneware, hard pottery made from siliceous paste, fired at high temperature to vitrify (make glassy) the body. Stoneware is heavier and more opaque than porcelain and differs from terra-cotta in bein...

(Encyclopedia) wapiti wŏpˈĭtē [key], large North American deer, Cervus canadensis, closely related to the Old World red deer. It is commonly called elk in America although the name elk is used in Europe to refer...

(Encyclopedia) quasar kwāˈsär [key], one of a class of blue celestial objects having the appearance of stars when viewed through a telescope and currently believed to be the most distant and most luminous objects...

(Encyclopedia)  CE5 spectral class, in astronomy, a classification of the stars by their spectrum and luminosity. In 1885, E. C. Pickering began the first extensive attempt to classify the stars spectroscopically....

(Encyclopedia) Gram's stain, laboratory staining technique that distinguishes between two groups of bacteria by the identification of differences in the structure of their cell walls. The Gram stain, named after its...

(Encyclopedia) Delhi dĕlˈē [key], union territory and city, N central India. The union territory, officia...

(Encyclopedia) streptococcus strĕpˌtəkŏkˈəs [key], any of a group of gram-positive bacteria, genus Streptococcus, some of which cause disease. Streptococci are spherical and divide by fission, but they remain ...

(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) logwood, small, thorny tree (Haematoxylon campechianum) of the family Leguminosae (pulse family) native to tropical America and introduced into other tropical regions. The brown-red heartwood is the s...