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fluoridation

(Encyclopedia)fluoridation flo͝orˌĭdāˈshən [key], process of adding a fluoride to the water supply of a community to preserve the teeth of the inhabitants. Tooth enamel ordinarily contains small amounts of fl...

Jaipur

(Encyclopedia)Jaipur jīˈpo͝or [key], former native state, W India. It is now part of Rajasthan state. The region of Jaipur is semiarid and mostly level, with scattered rocky hills. Despite light rainfall, fair c...

artesian well

(Encyclopedia)artesian well, deep drilled well through which water is forced upward under pressure. The water in an artesian well flows from an aquifer, which is a layer of very porous rock or sediment, usually san...

Northumberland

(Encyclopedia)Northumberland nôrthŭmˈbərlənd [key], county (1991 pop. 300,600), 2,019 sq mi (5,229 sq km), NE England; administratively, Northumberland is a unitary authority (since 2009). Northernmost of the ...

Ontario, Lake

(Encyclopedia)Ontario, Lake, 7,540 sq mi (19,529 sq km), 193 mi (311 km) long and 53 mi (85 km) at its greatest width, between SE Ont., Canada, and NW N.Y.; smallest and lowest of the Great Lakes. It has a surface ...

paralysis

(Encyclopedia)paralysis or palsy pôlˈzē [key], complete loss or impairment of the ability to use voluntary muscles, usually as the result of a disorder of the nervous system. The nervous tissue that is injured m...

Lyons, Second Council of

(Encyclopedia)Lyons, Second Council of, 1274, 14th ecumenical council of the Roman Catholic Church. It was summoned by Pope Gregory X to discuss problems in the Holy Land, to remove the schism of East and West, and...

Petronas Towers

(Encyclopedia)Petronas Towers, twin skyscrapers in Kuala Lumpur, Malaysia, that are the world's tallest twin towers. Standing 1,483 ft (452 m) high, they were designed by the Argentinian-American architect César P...

pollution allowance

(Encyclopedia)pollution allowance or emission rights, government-issued permit to emit a certain amount of a pollutant. The holder of the permit may use it to pollute legally, may trade permits, or may sell the per...

pontoon

(Encyclopedia)pontoon, one of a number of floats used chiefly to support a bridge, to raise a sunken ship, or to float a hydroplane or a floating dock. Pontoons have been built of wood, of hides stretched over wick...