PITCH - 9 reference results
tar and pitch, viscous, dark-brown to black substances obtained by the destructive distillation of coal, wood, petroleum, peat, and certain other organic materials. The heating or partial burning of wood to make charcoal yields tar as a byproduct and is an ancient method for the production of both tar and pitch. Coal tar is a residue in the manufacture of coal gas and coke. By the application of heat, tar is separated into several materials, one of which is pitch. The terms tar and pitch are loosely applied to the many varieties of the two substances, sometimes interchangeably. For example, asphalt, which is naturally occurring pitch, is called mineral tar and mineral pitch. Tar is more or less fluid, depending upon its origin and the temperature to which it is exposed. Pitch tends to be more solid. When ships were made of wood, tar had numerous uses, and an available supply of tar was an important factor in maritime growth. Tar made vessels watertight and protected their ropes from deterioration. All but small quantities of the tar now produced is fractionally distilled to yield naphtha, creosote, carbolic oil, and other equally important crude products. Among the substances produced by refining the various crude materials are benzene, toluene, cresol, and phenol. Tar from pine wood is used in making soap and medicinal preparations. Pitch is used in the manufacture of roofing paper, in varnishes, as a lubricant, and as a binder for coal dust in the making of briquettes used as fuel. Coal-tar derivatives are used in the manufacture of dyes, cosmetics, and synthetic flavoring extracts.
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pitch pine, common name for the species Pinus rigida, a small pine of the northeastern coastal United States.
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pitch, in music, the position of a tone in the musical scale, today designated by a letter name and determined by the frequency of vibration of the source of the tone. Pitch is an attribute of every musical tone; the fundamental, or first harmonic, of any tone is perceived as its pitch. The earliest successful attempt to standardize pitch was made in 1858, when a commission of musicians and scientists appointed by the French government settled upon an A of 435 cycles per second; this standard was adopted by an international conference at Vienna in 1889. In the United States, however, the prevailing standard is an A of 440 cycles per second. Before the middle of the 19th cent., pitch varied according to time, place, and medium of musical performance; since the classical period the trend has been gradually upward. The relative pitch of a tone, in contrast to absolute pitch, is an expression of its pitch in relation to the pitch of some other tone taken as a standard.
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pitch: see tar and pitch.
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absolute pitch, the position of a tone in the musical scale determined according to its number of vibrations per second, irrespective of other tones. The term also denotes the capacity to identify any tone upon hearing it sounded alone or to sing any specified tone. Experiments have shown that this ability, a form of memory, can be acquired through practice, but in some individuals it appears to be inborn.
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Licensed from Columbia University Press
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Pitch Lake, pool of pitch (asphalt), c.114 acres (46 hectares), SW Trinidad island, Trinidad and Tobago, near La Brea. The lake is believed to be formed and supplied by the seepage of natural pitch, a form of petroleum, from the surrounding oil-rich region. The pitch, hard around the edges of the pool, becomes more viscous toward the center. The seemingly inexhaustible supply has yielded millions of tons of pitch since the 16th cent. Fossils of prehistoric animals have been found in Pitch Lake, which has also become a tourist attraction.
The Columbia Electronic Encyclopedia Copyright © 2004.
Licensed from Columbia University Press
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In music, position of a single sound in the complete range of sound; this quality varies with the number of vibrations per second (hertz, Hz) of the sounding body and is perceived as highness or lowness. A higher pitch has a higher number of vibrations. In Western music, standard pitches have long been used to facilitate tuning. A confusing variety of pitches prevailed until the 19th century, when the continual rise in pitch made some international agreement a matter of practical necessity. In 1939 the A above middle C was standardized as 440 Hz. Seealso interval; tuning and temperament.
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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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