Columbia Encyclopedia

(Encyclopedia) spinel, magnesium aluminum oxide, MgAl2O4, a mineral crystallizing in the isometric system, usually as octahedrons. It occurs as an accessory mineral in basic igneous rocks, in aluminum-rich metamorph...

(Encyclopedia) Grayson, Cary Travers, 1878–1938, American naval officer and surgeon, b. Culpeper co., Va. As a physician he entered (1903) the U.S. navy, was graduated (1904) from the navy medical school, and afte...

(Encyclopedia) mango măngˈgō [key], evergreen tree of the Anacardiaceae (sumac family), native to tropical E Asia and now grown in both hemispheres. The chief species, Mangifera indica, is believed to have been c...

(Encyclopedia) blackbird, common name in North America of a perching bird allied to the bobolink, the meadow lark, the oriole, and the grackle and belonging to the family Icteridae. The European blackbird, Turdus me...

(Encyclopedia)  CE5 chlorophyll klôrˈəfĭlˌ [key], green pigment that gives most plants their color and enables them to carry on the process of photosynthesis. Chemically, chlorophyll has several similar forms...

(Encyclopedia) Mabinogion măbĭnōˈgēən [key], title given to a collection of medieval Welsh stories. Scholars differ as to the meaning of the word mabinogion: some think it to be the plural of the Welsh word ma...

(Encyclopedia) Atchafalaya əchăˈfəlīˌə [key], navigable river, c.170 mi (270 km) long, S central La. The Atchafalaya meanders south, in a former channel of the Mississippi, to the Gulf of Mexico. A distributa...

(Encyclopedia) Bab el Mandeb băb ĕl mănˈdĕb [key] [Arab.,= gate of tears], strait, 17 mi (27 km) wide, linking the Red Sea with the Gulf of Aden and separating the Arabian peninsula from E Africa. It is an impo...

(Encyclopedia) Pecos pāˈkəs [key], city (1990 pop. 12,069), seat of Reeves co., W Tex., on the Pecos River; inc. 1903. It is a railroad and highway junction and the market for an extensive ranch and irrigated far...

(Encyclopedia) Ouachita Mountains, range of east-west ridges between the Arkansas and Red rivers, extending c.200 mi (320 km) from central Ark. into SE Okla. Magazine Mt. (c.2,800 ft/850 m high) is the tallest peak....