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Rh brilliant and accomplished performer, and an excellent if an eccentric teacher; but his own compositions have not survived.  VOGT, KARL CHRISTOPH (1817–1895), German naturalist and geologist, was born at Giessen on the 5th of July 1817. In 1847 he became professor of zoology at Giessen, and in 1852 professor of geology and afterwards also of zoology at Geneva, where he died on the 5th of May 1895. His earlier publications were on zoology; he dealt with the Amphibia (1839), Reptiles (1840), with Mollusca and Crustacea (1845) and more generally with the invertebrate fauna of the Mediterranean (1854).

His separate works include Im Gebirg und auf den Gletschern (1843); Physiologische Briefe (1845-46); Grundriss der Geologie (1860); and Lehrbuch der Geologie und Petrefactenkunde (2 vols., 1846-47; ed. 4, 1879). An English version of his Lectures on Man: his Place in Creation and in the History of the Earth was published by the Anthropological Society of London in 1864.  VOGTLAND, or, a district of Germany, forming the S.W. corner of the kingdom of Saxony, and also embracing parts of the principality of Reuss and of the duchies of Saxe-Altenburg and Saxe-Weimar. It is bounded on the N. by the principalities of Reuss, in the S.E. by Bohemia, and on the S.W. and W. by Bavaria. Its character is generally mountainous, and geologically it belongs to the Erzgebirge range. It is extremely rich in mineral ores—silver, copper, lead and bismuth. The name denoted the country governed for the emperor by a Vogt (bailiff or steward), and was, in the middle ages, known as terra advocatorum. The Vögte are first met with in the country in the 10th century, and the office shortly afterwards appears to have become hereditary in the princely line of Reuss. But this house was not in undivided possession, rival claims being raised from time to time; and after being during the middle ages a bone of contention between Bohemia, the burgraves of Nuremberg and the Saxon house of Wettin, it passed gradually to the Wettins, falling by the division of 1485 to the Ernestine branch of the family. The elector Augustus I. made it one of the circles of his dominions.

See Limmer, Geschichte des Vogtlandes (Gera, 1825-28, 4 vols.); Simon, Das Vogtland (Meissen, 1904); C. F. Collmann, Das Vogtland im Mittelalter (Greiz, 1892); and Metzner, Vogtländische Wanderungen (Annaberg, 1902).  VOGÜÉ, EUGÈNE MELCHIOR, (1848–), French author, was born at Nice on the 25th of February 1848. He served in the campaign of 1870, and on the conclusion of the war entered the diplomatic service, being appointed successively attaché to the legations at Constantinople and Cairo and secretary at St Petersburg. He resigned in 1882, and from 1893 to 1898 was deputy for Ardèche. His connexion with the Revue des deux mondes began in 1873 with his Voyage en Syrie et en Palestine, and subsequently he was a frequent contributor. He did much to awaken French interest in the intellectual life of other countries, especially of Russia, his sympathy with which was strengthened by his marriage in 1878 with a Russian lady, the sister of General Annenkov De Vogüé was practically the first to draw French attention to Dostoievski and his successors. He became a member of the French Academy in 1888.

His works include: Histoires orientales (1879); Portraits du siècle (1883); Le Fils de Pierre le Grand (1884); Histoires d’hiver (1885); Le Roman russe (1886); Regards historiques et litteraires (1892); Cœurs russes (1894); Devant le siècle (1896); Jean d’Agrève (1898); Le Rappel des ombres (1900); Le Maître de la mer (1903); Maxime Gorky (1905).  VOICE (Fr. voix, from Lat. vox), the sound produced by the vibrations of the vocal cords, two ligaments or bands of fibrous elastic tissue situated in the larynx. It is to be distinguished from speech, which is the production of articulate sounds intended to express ideas. Many of the lower animals have voice, but none has the power of speech in the sense in which man possesses that faculty. There may be speech without voice, as in whispering, whilst in singing a scale of musical tones we have voice without speech. (See ; and for speech see ; also the articles on the various letters of the alphabet.)

1. Physiological Anatomy.—The organ of voice, the larynx,

is situated in man in the upper and fore part of the neck, where it forms a well-known prominence in the middle line (see details under ). It opens below into the trachea or windpipe, and above into the cavity of the pharynx, and it consists of a framework of cartilages, connected by elastic membranes or ligaments, two of which constitute the true vocal cords. These cartilages are movable on each other by the action of various muscles, which thus regulate the position and the tension of the vocal cords. The trachea conveys the blast of air from the lungs during expiration, and the whole apparatus may be compared to an acoustical contrivance in which the lungs represent the wind chest and the trachea the tube passing from the wind chest to the sounding body contained in the larynx. Suppose two tight bands of any elastic membrane, such as thin sheet india-rubber, stretched over the end of a wide glass tube so that the margins of the bands touched each other, and that a powerful blast of air is driven through the lube by a bellows. The pressure would so distend the margins of the membrane as to open the aperture and allow the air to escape; this would cause a fall of pressure, and the edges of the membrane would spring back by their elasticity to their former position; again the pressure would increase, and again the edges of the membrane would be distended, and those actions would be so quickly repeated as to cause the edges of the membrane to vibrate with sufficient rapidity to produce a musical tone, the pitch of which would depend on the number of vibrations executed in a second of time. In other words, there would be a rapid succession of puffs of air. The condensation and rarefaction of the air thus produced are the chief cause of the tone, as H. von Helmholtz has pointed out, and in this way the larynx resembles the siren in its mode of producing tone. It is evident also that the intensity or loudness of the tone would be determined by the amplitude of the vibrations of the margins of the membrane, and that its pitch would be affected by any arrangements effecting an increase or decrease of the tension of the margins of the membrane. The pitch might also be raised by the strength of the current of air, because the great amplitude of the vibrations would increase the mean tension of the elastic membrane. With tones of medium pitch, the pressure of the air in the trachea is equal to that of a column of mercury of 160 mm.; with high pitch, 920 mm.; and with notes of very high pitch, 945 mm.; whilst in whispering it may fall as low 