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Henry Cort
Henry Cort 1740-1800, English inventor. He revolutionized the British iron industry with his use of grooved rollers to finish iron, replacing the process of hammering, and through his invention of the puddling process. This process, called puddling, involved stirring the molten pig iron in a reverb...
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funny bone
funny bone highly sensitive area at the back of the elbow where the ulnar nerve passes close to the surface of the skin in a groove between end prominences of the humerus (the upper arm bone) and the ulna (the large forearm bone). A blow to the area causes the nerve to compress against bone, produc...
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kneecap
kneecap (patella), saucer-shaped bone at the front of the knee joint; it protects the ends of the femur, or thighbone, and the tibia, the large bone of the foreleg. The kneecap is embedded in the tendon tissue of the quadriceps femoris, a large thigh muscle. As the leg bends and straightens, the kn...
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record player
record player or phonograph, device for reproducing sound that has been recorded as a spiral, undulating groove on a disk. This disk is known as a phonograph record, or simply a record (see sound recording ). In using a record player, a record is placed on the player's motor-driven turntable, ...
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caecilian
caecilian , any of the legless, tailless tropical amphibians of the family Caecilidae. Most adult caecilians resemble earthworms superficially but have vertebrate characteristics such as jaws and teeth. They range in size from 7 in. to 4.5 ft (18 cm-140 cm); most are about 1 ft (30 cm) long. Their b...
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click beetle
click beetle common name for members of the widespread beetle family Elateridae. Also called elater beetle, the click beetle has a hinge across the front of the body that allows it to flex, and a spine-and-groove arrangement on the underside of the body that provides a snapping mechanism. When a ...
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mojarra
mojarra , common name for a member of the family Gerridae, small tropical food fishes. The many American species are found chiefly off the S Atlantic coast but also along the Pacific coast. Mojarras are rarely over a foot (30 cm) in length and are silvery in color. The fins can be retracted into spe...
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portcullis
portcullis , grating or framework of strong bars of wood or iron, sharp-pointed at their lower ends, sliding vertically in the grooved jambs of a fortified portal as a protection in case of assault. First used in Roman times against Hannibal, the portcullis reached its highest development in the 12t...
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Clovis culture
Clovis culture a group of Paleo-Indians (see Americas, antiquity and prehistory of the ) known through artifacts first excavated in the early 1930s near Clovis, N.Mex. The artifacts, including chipped flint points known as Clovis points and a variety of additional stone tools, were found along wit...
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match
match small stick whose chemically coated tip bursts into flame when struck on a rough surface. Before the introduction of the match, fire was made by friction methods using the stick and the groove, the fire drill, or flint, tinder, and steel, or by employing a magnifying glass. Attempts in the 18...
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