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Fracastoro, Girolamo

(Encyclopedia)Fracastoro, Girolamo jērôˈlämō fräkästôˈrō [key], 1483–1553, Italian physician and poet. He was born in Verona, where he practiced after studying at Padua. He studied epidemic diseases and...

adsorption

(Encyclopedia)adsorption, adhesion of the molecules of liquids, gases, and dissolved substances to the surfaces of solids, as opposed to absorption, in which the molecules actually enter the absorbing medium (see a...

geometric problems of antiquity

(Encyclopedia)geometric problems of antiquity, three famous problems involving elementary geometric constructions with straight edge and compass, conjectured by the ancient Greeks to be impossible but not proved to...

loam

(Encyclopedia)loam, soil composed of sand, silt, clay, and organic matter in evenly mixed particles of various sizes. More fertile than sandy soils, loam is not stiff and tenacious like clay soils. Its porosity all...

Paul, Wolfgang

(Encyclopedia)Paul, Wolfgang, 1913–93, German physicist, Ph.D. Technical Univ., Berlin, 1939. A professor at the Univ. of Bonn from 1952, Paul developed an ion-trap technique (known as the Paul trap), which made ...

Walton, Ernest Thompson Sinton

(Encyclopedia)Walton, Ernest Thompson Sinton, 1903–95, Irish physicist, educated at Methodist College (Belfast), Trinity College (Dublin), and Cambridge. He became a fellow of Trinity College in 1934 and professo...

tunneling

(Encyclopedia)tunneling, quantum-mechanical effect by which a particle can penetrate a barrier into a region of space that would be forbidden by ordinary classical mechanics. Tunneling is a direct result of the wav...

Davy, Sir Humphry

(Encyclopedia)Davy, Sir Humphry, 1778–1829, English chemist and physicist. The son of a woodcarver, he received his early education at Truro and was apprenticed (1795) to a surgeon-apothecary at Penzance. While d...

Freeman, Orville Lothrop

(Encyclopedia)Freeman, Orville Lothrop, 1918–2003, American political figure, b. Minneapolis. In World War II he served in the U.S. marine corps, was severely wounded, and was discharged with the rank of major in...

area

(Encyclopedia)CE5 area, measure of the size of a surface region, usually expressed in units that are the square of linear units, e.g., square feet or square meters. In elementary geometry, formulas for the areas...