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hail, in meteorology

(Encyclopedia)hail, precipitation in the form of pellets composed of ice or of ice and snow, occurring at any time of the year, usually during the passage of a cold front or during a thunderstorm. Small hailstones ...

Bergson, Henri

(Encyclopedia)Bergson, Henri äNrēˈ bĕrgsôNˈ [key], 1859–1941, French philosopher. He became a professor at the Collège de France in 1900, devoted some time to politics, and, after World War I, took an inte...

Bingham, George Caleb

(Encyclopedia)Bingham, George Caleb, 1811–79, American painter and politician, b. Augusta co., Va. His family moved (1819) to Missouri, which was the site of most of Bingham's activities. In 1837 he studied for a...

atomic clock

(Encyclopedia)atomic clock, electric or electronic timekeeping device that is controlled by atomic or molecular oscillations. A timekeeping device must contain or be connected to some apparatus that oscillates at a...

sea level

(Encyclopedia)sea level, the level of the sea, which serves as the datum used for measurement of land elevations and ocean depths. Theoretically, one would expect sea level to be a fixed and permanent horizontal su...

pendulum

(Encyclopedia)pendulum, a mass, called a bob, suspended from a fixed point so that it can swing in an arc determined by its momentum and the force of gravity. The length of a pendulum is the distance from the point...

clock

(Encyclopedia)CE5 A pendulum clock: Weight-driven clock mechanism clock, instrument for measuring and indicating time. Predecessors of the clock were the sundial, the hourglass, and the clepsydra. See also watc...

obscenity

(Encyclopedia)obscenity, in law, anything that tends to corrupt public morals by its indecency. The moral concepts that the term connotes vary from time to time and from place to place. In the United States, the wo...

megatherium

(Encyclopedia)megatherium mĕgəthērˈēəm [key] [Gr.,=large beast], extinct ground sloth, of the genus Megatherium, that was widely distributed in North and South America in the Pleistocene epoch. Fossil evidenc...

Ratas, Jüri

(Encyclopedia)Ratas, Jüri, 1978–, Estonian political leader. A member of the Center party, a populist party with strong support among ethnic Russians, Ratas was mayor of Talinn (2005–7), before entering the Es...