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Atlas Mountains

(Encyclopedia)Atlas Mountains, system of ranges and plateaus in NW Africa, extending c.1,500 mi (2,410 km) from SW Morocco, through N Algeria, to N Tunisia; Jebel Toubkal (13,671 ft/4,167 m), in SW Morocco, is the ...

Lancaster, Joseph

(Encyclopedia)Lancaster, Joseph, 1778–1838, English educator. In 1801 he founded a free elementary school, using a type of monitorial system for which he acknowledged his debt to Andrew Bell. The Royal Lancasteri...

heart-lung machine

(Encyclopedia)heart-lung machine, device that maintains the circulation of the blood and the oxygen content of the body when connected with the arteriovenous system; it is also called the pump oxygenator. The machi...

corvée

(Encyclopedia)corvée kôrvāˈ [key], under the feudal system, compulsory, unpaid labor demanded by a lord or king and the system of such labor in general. There were national and local variations, but in broad te...

control systems

(Encyclopedia)control systems, combinations of components (electrical, mechanical, thermal, or hydraulic) that act together to maintain actual system performance close to a desired set of performance specifications...

exoplanet

(Encyclopedia)exoplanet or extrasolar planet, a planet located outside the solar system. See planet; planetary system. ...

standpipe

(Encyclopedia)standpipe, tank or pipe for holding water in an elevated position to create pressure in a water supply system. For a tall building, where the pressure from the mains at street level is insufficient to...

stimulant

(Encyclopedia)stimulant, any substance that causes an increase in activity in various parts of the nervous system or directly increases muscle activity. Cerebral, or psychic, stimulants act on the central nervous s...

anatomy

(Encyclopedia)anatomy ənătˈəmē [key], branch of biology concerned with the study of body structure of various organisms, including humans. Comparative anatomy is concerned with the structural differences of pl...

rapid transit

(Encyclopedia)rapid transit, transportation system designed to allow passenger travel within or throughout an urban area, usually employing surface, elevated, or underground railway systems or some combination of t...