(Encyclopedia) hardening, in metallurgy, treatment of metals to increase their resistance to penetration. A metal is harder when it has small grains, which result when the metal is cooled rapidly.…
(Encyclopedia) Donner Party, group of emigrants to California who in the winter of 1846–47 met with one of the most famous tragedies in Western history. The California-bound families were mostly from…
(Encyclopedia) Petraeus, David HowellPetraeus, David Howellpĕtrāˈəs [key], 1952–, American military officer and government official, b. Cornwall, N.Y., studied West Point (B.S., 1974), U.S. Army…
(Encyclopedia) parity or space parity, in physics, quantity that refers to the relationship between an object or process and the image that it can produce in a mirror. For example, any right-handed…
(Encyclopedia) Lippman, Gabriel Jonas, 1845–1921, French physicist, Ph.D. Sorbonne, 1875. He was a professor at the Sorbonne from 1883 until his death in 1921. Lippman received the 1908 Nobel Prize…
(Encyclopedia) montagemontagemŏntäzhˈ, Fr. môNtäzhˈ [key], the art and technique of motion-picture editing in which contrasting shots or sequences are used to effect emotional or intellectual…
(Encyclopedia) Metcalfe, Charles Theophilus Metcalfe, 1st Baron, 1785–1846, British colonial administrator, b. India. He entered the Indian civil service as a young man, rose quickly, and was…
(Encyclopedia) Horrocks or Horrox, JeremiahHorrocks or Horrox, Jeremiahboth: hŏrˈəks [key], 1618?–1641, English astronomer. He made the first observation of the transit of Venus. His Venus in sole…
