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Welsbach mantle

(Encyclopedia)Welsbach mantle or Welsbach burner [for C. A. von Welsbach], cylindrical framework of gauze impregnated with oxides of thorium and cerium. When heated in a gas flame, it produces a very bright light b...

giant clam

(Encyclopedia)giant clam, common name for the largest bivalve mollusk in the world, Tridacna gigas, also known as the bear's paw clam. The giant clam may weigh over 500 lb (225 kg) and attain a length of over 4 ft ...

Pyramus and Thisbe

(Encyclopedia)Pyramus and Thisbe pĭrˈəməs, thĭzˈbē [key], in classical mythology, youth and maiden of Babylon, whose parents opposed their marriage. Their homes adjoined, and they conversed through a crevice...

bivalve

(Encyclopedia) CE5 Internal anatomy of a clam, Anodonta, representative mollusk of the class Pelecypoda (the bivalves) bivalve, aquatic mollusk of the class Pelecypoda (“hatchet-foot”) or Bivalvia, with a la...

petrology

(Encyclopedia)petrology, branch of geology specifically concerned with the origin, composition, structure, and properties of rocks, primarily igneous and metamorphic, and secondarily sedimentary. It includes petrog...

Mays, Willie Howard, Jr.

(Encyclopedia)Mays, Willie Howard, Jr. (“Say Hey” Willie Mays), 1931–, American baseball player, b. Fairfield, Ala. He began his professional career at 17 with the Black Barons of the Negro National League. I...

scallop

(Encyclopedia)scallop or pecten, marine bivalve mollusk. Like its close relative the oyster, the scallop has no siphons, the mantle being completely open, but it differs from other mollusks in that both mantle edge...

earth, in geology and astronomy

(Encyclopedia) CE5 A. Cross section of the earth, showing its shells B. Detailed cross section of the crust and upper mantle: The lithosphere consists of the hard rock in the crust and upper mantle, lying above t...

chiton

(Encyclopedia) CE5 A. Dorsal view of a chiton, representative mollusk of the class Amphineura B. Internal anatomy of a chiton chiton kīˈtən [key], common name for rock-clinging marine mollusks of the class Po...

Mohole, Project

(Encyclopedia)Mohole, Project, program proposed in 1957 to drill a hole down to the boundary between the crust and the mantle, known as the Mohorovičić discontinuity at about 4 to 43 mi (7 to 70 km) below the ear...
 

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