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hardpan

(Encyclopedia)hardpan, condition of the soil or subsoil in which the soil grains become cemented together by such bonding agents as iron oxide and calcium carbonate, forming a hard, impervious mass. It is disadvant...

pencil

(Encyclopedia)pencil, pointed implement used in writing or drawing to apply graphite or a similar colored solid to any surface, especially paper. From prehistoric times lumps of colored earth or chalk were used as ...

Adams, John Quincy

(Encyclopedia)Adams, John Quincy, 1767–1848, 6th President of the United States (1825–29), b. Quincy (then in Braintree), Mass.; son of John Adams and Abigail Adams and father of Charles Francis Adams (1807–8...

Bessemer process

(Encyclopedia)CE5 Bessemer converter Bessemer process bĕsˈəmər [key] [for Sir Henry Bessemer], industrial process for the manufacture of steel from molten pig iron. The principle involved is that of oxidati...

National Road

(Encyclopedia)National Road, U.S. highway built in the early 19th cent. At the time of its construction, the National Road was the most ambitious road-building project ever undertaken in the United States. It final...

oratory

(Encyclopedia)oratory, the art of swaying an audience by eloquent speech. In ancient Greece and Rome oratory was included under the term rhetoric, which meant the art of composing as well as delivering a speech. Or...

Rogers, John, American sculptor

(Encyclopedia)Rogers, John, 1829–1904, American sculptor, b. Salem, Mass. Trained as an engineer, he was forced by failing eyesight to work as a machinist. He began modeling in clay as a pastime and studied sculp...

silt

(Encyclopedia)silt, predominantly quartz mineral particles that are between sand size and clay size, i.e., between 1⁄16 and 1⁄256 mm (1⁄406 –1⁄6502 in.) in diameter. Silt, like clay and sand, is a product...

golem

(Encyclopedia)golem gōˈləm [key] [Heb.,=an undeveloped lump], in medieval Jewish legend, an automatonlike servant made of clay and given life by means of a charm, or shem [Heb.,=name, or the name of God]. Golems...

pottery

(Encyclopedia)pottery, the baked-clay wares of the entire ceramics field. For a description of the nature of the material, see clay. American art pottery flourished in the first half of the 20th cent., with wor...