Columbia Encyclopedia

Search results

500 results found

Bell, Gertrude Margaret Lowthian

(Encyclopedia)Bell, Gertrude Margaret Lowthian lōˈᵺēən [key], 1868–1926, British traveler, author, and government official, one of the builders of the modern state of Iraq, grad. Oxford, 1887. From 1899 on ...

tempera

(Encyclopedia)tempera tĕmˈpərə [key], painting method in which finely ground pigment is mixed with a solidifying base such as albumen, fig sap, or thin glue. When used in mural painting it is also known as fres...

diffusion

(Encyclopedia)diffusion, in chemistry, the spontaneous migration of substances from regions where their concentration is high to regions where their concentration is low. Diffusion is important in many life process...

continental drift

(Encyclopedia)CE5 Continental drift (arrows indicate the directions of motion of the landmasses) A. Proposed reconstruction of the supercontinent Pangaea indicating the major present landmasses B. Proposed recon...

friction

(Encyclopedia)friction, resistance offered to the movement of one body past another body with which it is in contact. In certain situations friction is desired. Without friction the wheels of a locomotive could not...

parallax

(Encyclopedia)CE5 The trigonometric parallax of a star, expressed by the angle θ, is a measure of its apparent motion against the background of more distant stars as a result of the earth's motions in its orbit...

differential

(Encyclopedia)differential, in the automobile, a set of gears used on the driving (usually rear) axle. The two wheels on the driving axle must be interconnected in order to receive their energy from the same source...

horology

(Encyclopedia)horology hōrŏlˈəjē [key], science of measuring time and technology of constructing instruments for its measurement or recording. Early measurements of the passage of time were based on observatio...

Halley, Edmond

(Encyclopedia)Halley, Edmond hălˈē, hôˈlē [key], 1656–1742, English astronomer and mathematician. He is particularly noted as the first astronomer to predict the return of a comet and the first to point out...

Hollywood

(Encyclopedia)Hollywood. 1 Community (2020 population 35,757) within the city of Los Angeles, S Calif., on the slopes of the Santa Monica Mts.; inc. 1903, ...