Columbia Encyclopedia

Search results

500 results found

Canyonlands National Park

(Encyclopedia)Canyonlands National Park, 337,598 acres (136,679 hectares), SE Utah; est. 1964. Located in a desert region, the park contains a maze of deep canyons and many unusual features carved by wind and water...

hurricane

(Encyclopedia)CE5 View into the eye of a hurricane showing the structure of the surrounding cloud wall hurricane, tropical cyclone in which winds attain speeds greater than 74 mi (119 km) per hr. Wind speeds gu...

superconductivity

(Encyclopedia)superconductivity, abnormally high electrical conductivity of certain substances. The phenomenon was discovered in 1911 by Heike Kamerlingh Onnes, who found that the resistance of mercury dropped sudd...

ventilation

(Encyclopedia)ventilation, process of supplying fresh air to an enclosed space and removing from it air contaminated by odors, gases, or smoke. Proper ventilation requires also that there be a movement or circulati...

hydrogen bomb

(Encyclopedia)hydrogen bomb or H-bomb, weapon deriving a large portion of its energy from the nuclear fusion of hydrogen isotopes. In an atomic bomb, uranium or plutonium is split into lighter elements that togethe...

circulatory system

(Encyclopedia)CE5 Circulatory system circulatory system, group of organs that transport blood and the substances it carries to and from all parts of the body. The circulatory system can be considered as compose...

Sahara

(Encyclopedia)Sahara səhârˈə [key] [Arab.,=desert], world's largest desert, c.3,500,000 sq mi (9,065,000 sq km), N Africa; the western part of a great arid zone that continues into SW Asia. Extending more than ...

respiration

(Encyclopedia)CE5 Respiratory system respiration, process by which an organism exchanges gases with its environment. The term now refers to the overall process by which oxygen is abstracted from air and is tran...

Makarios III

(Encyclopedia)Makarios III mäkäˈrēôs [key], 1913–77, Orthodox Eastern archbishop and Cypriot statesman, first president of Cyprus (1960–77). Born Michael Mouskos, Makarios was elected bishop of Kition in 1...

martial arts

(Encyclopedia)martial arts, various forms of self-defense, usually weaponless, based on techniques developed in ancient China, India, and Tibet. In modern times they have come into wide use for self-protection, as ...