Page images
PDF
EPUB
[merged small][merged small][merged small][merged small][graphic]
[graphic]

St. Sebald's Tomb at Nuremberg, by Vischer. in virtue of these he was reckoned by contemporaries as next to Albert Durer. Little is known of his life. His sons were also distinguished as sculptors and workers in bronze.

Viscidity. Property of a viscous fluid in virtue of which it can, like melted glass, be drawn out into fine threads; e.g., fluid from which a spider spins his web.

Visconti. Lombard house, long supreme in Milan. OTTONE, or OTHO, 1208-1295, became Abp. 1263: his nephew, MATTEO, 1250-1322, was Viscount 1311-22.-GALEAZZO I., 12771328, formed an imperial alliance and defeated a papal army. -GALEAZZO II., 1320-1378, founded the Univ. of Pavia and patronized Petrarch.-His son, GIAN, 1347-1402, ruled 13781402, became Duke, and enlarged his dominions. The male line ended 1447: the Sforzas succeeded.

Visconti, GIAUBATTISTA, 1722-1784. Prefect of antiquities at Rome from 1768; curator of the museum founded by Clement XIV. His son, ENNIO QUIRINO, 1751-1818, prof. Paris from 1799, pub. Iconographie Grecque, 1808, and Iconographie Romaine, 1818-20. Opere tutte, 21 vols., 1824.-His son, LOUIS TULLIUS JOACHIM, 1791-1853, was an architect in Paris.

Visconti Venosta, EMILIO, b. 1829. Italian Foreign Minister 1863-64, 1866-67, and 1869-76; Senator 1886.

Viscosity. When a fluid is subjected to a deforming force, the strain produced is proportional to the time the force acts. The resistance to this continuous change of form, depending on the velocity of the change, is called viscosity. It varies in amount from that of tar or sealing-wax to that of ether or hydrogen. This term is sometimes applied to an elastic solid, capable of vibrating, to explain the fact that in time the motion ceases, the energy of vibration being converted into heat. This viscosity or imperfect elasticity makes it impracticable to employ lead or zinc in the construction of tuning-forks. Superficial viscosity is the property of the surface films of liquids on account of which frothing may result from agitation, providing the surface tension be not too great. A fluid with infinite viscosity would not differ from a rigid solid (see COEFFICIENT OF VISCOSITY). The discovery of the viscosity of fluids in general is due to Prof. Stokes.

Viscount. In Britain, rank between earl and baron; first bestowed 1440, on John Beaumont.

Vise. Spiral staircase, in the Norman style, with the steps resting upon a continuous spiral vault; subsequently, each step was a single stone, the outer end inserted in the wall, the other end resting upon and forming part of the newel.

Vishnu. Preserver; middle deity of the Hindu Triad.

Vishnu as Narayana.

but less gloomy and cruel than that of Siva, the Destroyer. V. is generally represented as a dark-blue man with four arms. His most ardent worshipers are of the middle classes.

Visible Speech. System of symbols designed to represent every possible articulate utterance of the organs of speech. It was devised by Alex. M. Bell and first printed in 1867. The symbols are to a certain extent pictorial of the action of the organs which produce the sound. Consonants are represented by curves which have the outline of the organs they symbolize, and a straight line is the basis of all vowel symbols. With these, the curve and straight line, and their combinations, symbols for all the sounds are made.

Visigoths. See GOTHS.

Vision. Process that permits one to take cognizance of an object through the organ of sight; it involves the transmission of light from the object to the eye, its refraction by the dioptric apparatus of the eye, the exciting of nervous energy by the resulting image, which is conveyed to the brain and is there transformed into a sensation. See SIGHT, SENSATIONS OF.

Vision, DEFECTS OF. Anything that interferes with any factor in the complex process of vision will cause a defect. The media of the eye may not be transparent, there may be disease of the coats of the eye, of the optic nerve, or of the visual centers in the brain, and vision would be deficient for some organic cause; again the dioptric curves may be abnormal, or the muscular apparatus governing either the accommodation or convergence of the eyes may be deficient, and a defect of vision would result from a functional cause.

Vision. In Scripture, presentation, commonly in symbolic form, to the mind of a prophet or seer, of some spiritual truth; usually affecting the sight and hearing, but sometimes only the inner sense.

Visitation, FEAST OF. In R.C. Ch., July 2, commemorating the visit of the Virgin Mary to Elizabeth.

Visitation, NUNS OF THE. Order founded 1610 by St. Francis de Sales and Mme. de Chantal. It became monastic 1618, and spread rapidly, as later in America.

Visitation and Search. See SEARCH.

Visiting Cards. The origin of these can be traced directly in China, where the custom of exchanging cards is universal at New Year. Chinese cards are oblong strips of red paper, inscribed with the name of an individual or shop company. They are carefully preserved and pasted in a conspicuous place in the shop or dwelling through the year, forming a kind of pledge from friend or clansman. It may be inferred from their name that they were originally made of bamboo, and from their resemblance to the message arrow of China that they originated with the latter in the arrow marked with the

name or symbol of its owner.

Visp. Village of Vaud, where Swiss peasants defeated the Earl of Savoy 1388.

Vistula. River of Europe, which heads in the Carpathian Mts. of Austro-Hungary, and flows mainly n. across parts of Poland and Prussia to the Gulf of Dantzig, in the Baltic Sea. Length 696 m., drainage area 69,309 sq. m.

Visual Angle. See OPTIC AXIS.

Visualization. Act of calling up a mental picture with such distinctness as to simulate more or less completely an

VIS VIVA-VIVERRIDE

actual visual percept. Individuals differ greatly in visualizing power, some being able to form such distinct images that they are in effect looking upon the actual object or scene; a few are unable to form any visual image. Nearly every one has the faculty to some extent. See NUMBER FORMS.

Vis Viva. See LIVING FORCE.

Vit, VICENZO DE, 1811-1892. Italian priest, editor of Forcellini's Latin Lexicon, 6 vols., 1858-79, and compiler of Onomasticon, a list of proper names prior to 400.

Vitaceæ. See AMPELIDACEÆ.

Vitalianus. Pope 657-672. He and Maurus, Abp. of Ravenna, excommunicated each other.

Vitalis, ORDERICUS. 1075-ab.1143. English monk of St. Evroul, Normandy. His Hist. Ecclesiastica, extending to 1142, was tr. 1853-56; parts are of value.

Vital Statistics. Statistical information relating to the life history of a collection of individuals, whether an institution, a community, or a nation. It involves the gathering of the facts, their tabulation and certain deductions that may fairly be drawn from the premises furnished. Facts as to birth, marriage, sickness and death are the chief ones sought for. Carefully gathered and properly tabulated, vital statistics are of inestimable value in studying the economic and social condition of a country.

Vitebsk. City of w. Russia, at the junction of the Dwina and Viteba. Pop., 1890, 58,179.

Vitellarium. Special portion of the ovaries of turbellarian worms, insects, etc., which furnishes cells that are wholly transformed into yolk as food for the egg cells.

Vitelline Duct. That leading from the yolk-sac to the embryo in forms that have much food-yolk in the egg, as Reptiles and Birds.

Vitellius, AULUS, 15-69. Eighth Roman emperor; notorious for gluttony; proclaimed Jan. 69 at Cologne by his troops,

1617

Vitrified Forts. Prehistoric fortifications found in Scotland, built of siliceous stones, which have the inside and in some cases the entire fort vitrified by means of fire and wood ashes.

Vitringa, CAMPEGIUS, 1659-1722. Dutch theologian and voluminous Latin writer; prof. Franeker from 1683. His commentary on Isaiah, 1714-20, is still valued.

Vitriols. Hydrous metallic sulphates. Some of the vitriols are found in nature in small quantity as products of the alteration of metalliferous minerals, as copper vitriol, chalcanthite, CuSO,+5H,0; iron vitriol, melanterite, FeSO.+7H,O; zinc vitriol, goslarite, ZnSO,+7H,O.

Vitruvian Scroll. Scroll work of convolved undulations, used in Classical Architecture.

Vitruvius, POLLIO, 1st cent. B.C. Latin writer on architecture. His work was tr. 1771-91 and 1826.

Vittæ. Oil-tubes of the fruit of the Umbelliferæ. Vittoria. Town of e. Sicily; site of a defeat of Arabs by Roger I. 1092.

Vittoria, Town of n. Spain; site of Wellington's victory over the French commanded by Joseph Bonaparte and Mar

[graphic][merged small]

shal Jourdan, June 21, 1813. Ab.75,000 were on each side. Jourdan lost all his artillery.

Vittoria, ALESSANDRO, 1525-1608. Italian architect. Vittoria, TOMASO LUDOVICO DA. ab.1540-1608. Spanish ch. composer; colleague and friend of Palestrina.

Vitus, ST. Sicilian martyr ab.300; patron of dancers and actors; invoked by German peasants to cure the nervous disease named from him, and to insure health in general. His day is June 15.

Vivaldi, ANTONIO, d. 1743. Italian violinist. His most important compositions are those for violin, but he also wrote 29 operas, chiefly for Venice, where he was director of the Conservatorio della Pietà. J. S. Bach transcribed some of his violin concertos for clavier and organ.

Vivanco, MANUEL IGNACIO DE, 1806-1873. Peruvian revolutionist, in power 1843.

Vivandiere. Woman sutler, chiefly in French marching regiments; celebrated in Ouida's and other novels.

Vivarini, ANTONIO, d. 1470, and BARTOLOMMEO, d. ab. 1500. Venetian painters.

Viverridæ. Family of Eluroidea, having sharp muzzles, long tails, spotted or banded marks in the fur, and a semiplantigrade mode of progression. There are four premolars

[graphic]
[graphic]

Vitellius, from Bust in the Capitoline Museum.

who defeated Otho's but were beaten by those of Vespasian; slain Dec. 21.

Viterbo. Italian town, 42 m. n.w. of Rome, noted for its springs, bishop's palace, and ch. relics. Pop. ab. 16,500.

Vitet, LOUIS, 1802-1873. French poet and essayist. Etudes, 1864-74.

Vitiligo. Disease of the skin characterized by a deficiency of pigment, causing a well-defined white patch, of which there may be one or many. If on the hairy parts of the body, the hair also becomes white or drops out.

Vitreous. See ELECTRIFICATION.
Vitreous Copper. Chalcocite, Cu,S.

Vitreous Silver. Argentite, Ag2S.

Vitrification. Conversion of a material into another having a glassy or vitreous structure. It is assisted by alkalies and heat.

Zebra Mongoos (Herpestes fasciatus).

and two tuberculated molars in each series. Here belong the Civet cats, noted for the musky secretion of their anal glands, used as a pomade. The Genet is a variety domesticated in Europe, having rudimentary scent-glands. Allied is the Ich

[blocks in formation]

neumon (Herpestes), domesticated in Egypt, which lives on snakes, lizards, crocodile eggs, etc., and the Mongoos of India, celebrated for killing poisonous snakes. The Cryptoprocta of Madagascar belongs to a special subfamily, as does Proteles, the Aard-wolf of S. Africa, about as large as a fox, with feet as in dogs, a body like the hyena, and dentition truly viverrine.

Vives, JUAN LUIS, 1492-1540. Spanish humanist, tutor to Princess Mary of England 1523-28; teacher at Bruges from 1529; Latin writer on Aristotle, Virgil, and St. Augustine. Linguæ Latince Exercitatio, 1539. Works, 8 vols., 1782.

Viviani, DOMENICO, 1772-1840. Prof. of Botany in Genoa. Annali di Botanica, 1802; Flora Corsica, 1824-30.

Vivianite. Fe,P2O,+8H,O. Hydrous mineral, sometimes called blue iron earth, containing iron and phosphorus; product of mineral alteration, and, when associated with iron ores, an objectionable impurity on account of the phosphorus.

Vivien de St. Martin, LOUIS, 1802-1897. French writer on geography and history.

Vivier, JACQUES DU, 1720-1793. French botanist, long in Peru. Nova genera et species plantarum, 1788-90; Sertum Peruvinum, 1792.

Viviparous. 1. Giving birth to developed young; as opposed to OVIPAROUS (q.v.). All animals reproduce by means of eggs which, in viviparous forms, hatch within the mother. 2. Plants whose seeds or bulblets begin to grow before separation from the parent plant.

Vivisection. In Physiology, the employment of living animals to assist in solving problems relating to the perform

ance of the normal functions of an organ, the nature and effects of diseased conditions, or the effects of remedies. Animal experimentation has aided in making many valuable discoveries for the benefit of mankind.

Vizcaino, SEBASTIAN, ab.1550-1615. Spanish seaman, who explored the coast of California and Oregon 1602-3, and went to the Philippines and Japan 1610.

Vizier. Mohammedan dignitary; usually, since 752, chief minister of a sovereign. The Grand Vizier was head of the Sultan's councilors 1327-1878.

Vladikavkaz. Russian town, n. of the Caucasus, commanding the pass s. to Tiflis. Pop., 1892, 46,345.

Vladimir. Old town of Russia, 120 m. n.e. of Moscow. Its Kremlin and Golden Gate date from ab.1150-60. Pop. 18,305.

Vladivostok. Town of s.e. Siberia. on the Japan Sea; founded 1861. It has a fine harbor, and is of naval importance. Pop. ab. 15,000.

Vocal Music. Generally, all music written to be sung by the human voice; strictly, it does not include mixed forms, as songs, cantatas, oratorios, masses, and operas, in which the voices are accompanied by instruments. Its most perfect type is the so-called a capella music of the church, which reached its culmination in Palestrina.

Voclupiaceæ. Natural order of flowering plants, of the class Angiosperma, subclass Dicotyledons, and series Polypetala, comprising 7 genera and ab. 130 spécies. distributed through the tropical regions of America as far as Panama.

Voetius, GYSBERTUS, 1588-1676. Prof. Utrecht 1634; severe theologian, who wrote much against the Arminians or Remonstrants.

Vogdes, ISRAEL, U.S.A., 1816-1889. Brig.-gen. U. S. Vols. 1862-66, serving in Fla., S. C., and Va.

Vogel, ALFRED, 1829-1890. Prof. Dorpat 1866, and Munich 1886; writer on pathology. Kinderkrankheiten, 1860.

Vogel, EDUARD, 1829-1856. German explorer in n. central Africa from 1853; murdered in Wadai.

Vogel, JULIUS, b.1835. English official in Australia 1852-69. and New Zealand 1869-88.

Vogelweide. See WALTHER UM WOGELWEIDE.

Voghera. Ancient town of n.w. Italy, 16 m. s. w. of Pavia. Pop. ab. 13,000.

Vogler, GEORG JOSEPH, 1749-1814. German musician and teacher, celebrated in one of Browning's noblest poems, Abt Vogler, 1864. He elaborated a new system of fingering, con

trived to learn the violin and other instruments without a teacher, and founded schools of music at Mannheim, Stock

[graphic]

holm and Darmstadt. Weber and Myerbeer were among his pupils. He excelled in the department of harmony.

Vogt, CARL, 1817-1895. Prof. of Geology at Geneva from 1852. Lectures on Man, tr. 1864.

Vogüé, CHARLES JEAN MELCHIOR, MARQUIS DE. b.1829. French Orientalist; Academician 1868: envoy to Turkey 1871, and to Austria 1873.-His relative, EUGENE MARIE MELCHIOR, VICOMTE, b. 1848, is prominent as a critic and in the Neo-Christian movement. Le Roman Russe, 1886; Russian Portraits, tr.

1896.

Vogué, JEAN PIERRE DE, 1570-1630. Flemish soldier, treasure-hunter in the wilds of Brazil.

Voice. Appreciable sound produced by the air, when driven from the lungs, throwing the inferior ligaments of the glottis into vibration. See SINGING, SOUND, and TIMBRE.

Voice, Loss OF. See APHONIA.

Voight, FRIEDRICH SIEGMUND, 1781-1850. Prof. Jena. Botanischen Kunstsprache, 1803; Praktischen Botanik, 1850.

Voir Dire. Preliminary examination of a proposed witness to determine his competency.

Voisin, FRANÇOIS PHILIPPE, b. 1821. French engineer, director Suez Canal 1861-70; prof. Paris 1873-81. Ports de Mer, 1883; Travaux à l'Embouchure du Danube, 1893.

Voisin, PIERRE JOSEPH, 1759-1821. French writer on Guiana. Voiture, NICOLAS AUGUSTE, ab. 1764-1821. Chilian-French writer on Patagonia 1812-14; literary historian of S. America 1818.

Voiture, VINCENT. 1598-1648. French author of lyrics and epistles. Works, 1650; Lettres, 1880.

Vokes, ROSINA (MRS. C. CLAY), 1854-1894. English actress, often in the U. S.

Volapük. Universal language, invented 1879 by J. M. Schleyer, a German priest of Baden. It has 37 letters, each having always the same sound. It is simple and uniform in structure and arrangement. and easily learned. A grammar and dictionary were pub. 1880. It has been used in many books. Though received with some enthusiasm at first, interest in it seems to have declined.

Volatile Oils. Vegetable oils which boil without decomposition, as oil of turpentine. They may be hydrocarbons or compounds of more complicated nature.

Volcano. To the modern geologist, opening extending down into the earth and providing a way for the escape of molten and gaseous matter from below. The outbreak is in all probability caused by the access to heated rock of water, which, being suddenly converted into steam, develops enormous explosive force and produces an eruption. The lava forced up from below soon opens a way through the porous side of the crater and flows down, while vast quantities of the same material are violently blown from the crater, and, being

VOLES-VOLTAIC PILE

thereby reduced to powder, produce the volcanic dust, the heavier part of which falls again on and near the crater, while the lighter portion rises and floats away in the higher regions of the atmosphere, where much of it probably remains for months or even years. The volcano consequently builds up for itself a cone of the material thrown out of the crater, and forms a mountain of eruption. The study of volcanic lavas has thrown great light on the history of the primitive rocks of the globe, and the results of furnace experiments have in turn elucidated the formation of lavas by showing most of the volcanic products in their slags. The smoke often said to attend a volcanic eruption, is mostly the dust. The flame is chiefly the glare of the lava in the crater, reflected from the clouds, and the rain is in part at least due to the condensation of erupted steam. Some of the most remarkable outbreaks on record are the following: those of Etna from time immemorial, and of Vesuvius since 79; that at Tomboro in Sumbawa 1815, when nearly the whole population of the island was destroyed and the explosions were heard 1,000 m. away; the great eruption of the Skapta Jokul, in Iceland, 1783, when 10,000 persons and immense numbers of cattle perished and a thick haze overhung w. Europe for some months; that of Jorullo in Mexico, 1759, when a volcano was suddenly elevated to a height of 16.000 ft. in the midst of a vast plain previously covered with fertile fields of sugar-cane and indigo; that of Galung-Gung, in Java. 1822, when, in the midst of a dense forest in a fruitful and thickly peopled region, immense torrents of boiling water and mud were poured forth until in five hours not a trace of the villages and plantations remained. More recent still is the tremendous eruption of Krakatoa, in the same region, 1883, the details of which are yet fresh in the memory. The report of the committee sent out by the Royal Society of London forms a valuable and permanent record of this outbreak, the concussion of which was traced by the barometer three times round the globe before it died out, and the sunset glows produced by the dust were brilliant for months. The destruction of the pink and white terraces of Rotarua, New Zealand, 1886, and the eruption of the Mud Volcano of Bandaisan in Japan 1895, are among the most recent illustrations of volcanic action. Whymper estimated that in the eruption of Cotopaxi in 1880 2,000,000 tons of dust were discharged into the atmosphere. It was of an ashen color and consisted of fragments of lava and feldspar; the smallest particles were of an inch in diameter.

Voles. Rodents of the subfamily Arvicolina, of section MYOMORPHA (q.v.). In America they are called Field and Meadow Mice. Many species are included. They range from the Arctic regions to Texas, living in burrows in low, moist

Water Vole (Arvicola amphibius).

lands; some species are aquatic. They are small, not exceeding 5 in. in length. but very prolific, and destructive to grain and crops. They differ from mice in having short blunt muzzle, short limbs and tail, and low, nearly hidden ears.

Volga. Longest river in Europe. It heads in the Ural Mts. and the plains of central Russia, and flows into the Caspian Sea through an extensive delta. Length 2,330 m., drainage area 517,272 sq. m. It is of vast commercial importance, being navigable, except in winter, through nearly its entire course, as are many of its tributaries.

Volition. Active aspect of consciousness. It is commensurate with COGNITION and FEELING (q.v.) and interdependent with them. Every state of consciousness involves a volitional or conative element. Volition is based on impulse, and is itself impulse regulated and directed toward a recognized end, this end being felt as desirable. It follows then that volition or will involves knowledge and feeling: there must be knowledge of the end and the end must involve an emotional element with consequent interest. In a concrete volitional act, then, we have a state of desire followed by determination and choice between competing desires, and these become the motive of the action. If the action be unimpeded the will may be said to be free. See WILL.

1619

His works are chiefly portrait-busts. His son, STEPHEN ARNOLD DOUGLAS, b.1856, is a sculptor in Minneapolis.

Volkelt, JOHANNES, b.1848. Prof. Basel 1883, Würzburg 1889, and Leipzig 1894; writer on philosophy and pedagogy. Volkmann, FRIEDRICH ROBERT. 1815-1883. Prof. of Har

mony and Counterpoint at Pesth 1858; composer of two symphonies, D minor and B-flat major, three serenades for string orchestra, of which one in D minor with violoncello obbligato is much liked in the U. S., six string quartets, two overtures, and many miscellaneous pieces.

Volkslieder. German popular songs. 1300-1600.

Vollenhove. Town of Overyssel, on the Zuyder Zee, 12 m. n. w. of Zwolle. Here the Frisians defeated Rheinhold of Guelders 1323. Pop. 1,543.

Vollon, ANTOINE, b.1833. French painter, eminent especially as a colorist.

Volney, CONSTANTIN FRANÇOIS CHASSEBOEUF (BOISGIRAIS), COMTE DE, 1757-1820. Last of the French philosophes; Deputy 1789. His famous Ruins, 1791. brilliant. cynical, and antireligious, was extracted from Voyage in Egypte et en Syrie, 1787. Though a republican, he narrowly escaped the guillotine. In 1794 he befriended Bonaparte, and while in the U. S., 1795-99, predicted the successive steps of his Italian campaign. He became Senator 1799. Academician 1803, Count 1808, and Peer 1814. Tableau du Climat et du Sol, 1803. Works, 8 vols., 1820-26.

Volsci. Italian tribe s.e. of Rome, long its enemies; conquered and made citizens ab.338 B.C.

Volscian Language. That of the Volscians, related to the Umbrian.

Volsinii. Ancient name for Bolsena, a town of Italy ab. 20 m. n.w. of Viterbo. It was the capital of the Volsci, and taken by the Romans 280 B.C. Pop. ab. 3.000.

Volsk. Town of e. Russia, on the Volga, 70 m. n.e. of Saratoff. Pop.. 1890, 39,995.

Volsungs. Legendary race sprung from a grandson of Odin; celebrated in sagas.

Volt. Practical unit of difference of electrical potential or electromotive force; named for Volta. It is equal to 10° C.G.S. electromagnetic units. A megavolt is 1.000.000 volts; microvolt is one millionth of a volt. The electromotive force of a Daniell's cell is about one volt.

Volta, ALESSANDRO, 1745-1827. Prof. of Natural Philosophy at Pavia 1774-1804; pioneer electrician: inventor of the Voltaic pile; made count and senator by Bonaparte. Works, 5 vols., 1816.

Volta, LAW OF. Whenever two substances at the same temperature are brought in contact, a finite difference of potential is established between them, independent of their dimensions, form, extent of the surfaces in contact, and absolute value of the potential upon either of them. and dependent only upon the chemical or physical characters of the substances and the medium in which they are immersed.

Voltaic Arc. See ELECTRIC ARC.

Voltaic Pile. Apparatus contrived 1800 for producing electrification by metallic contact. Volta maintained that the effects observed by Galvani were due to the contact of two metals; his pile consists

of an alternating series of
disks of copper, zinc and wet
cloth, many times repeated.
If the lower copper and the
upper zinc of a considerable
series be connected by a wire,
a small spark may be ob-
served at the terminals. This
experiment excited great inter-
est. Volta described soon after-
ward the "crown of cups" or
series of cups in a circle, con- COPPER
taining salt water; in each of

[graphic]

CLOTH ZINC

Voltaic Pile.

SPARK

[graphic]

these was immersed a plate of copper and one of zinc, the

Volk, LEONARD WELLS, 1828-1895. Sculptor of Chicago. copper of each cup being joined with the zinc of the next,

[blocks in formation]

Bust of Voltaire, by Houdon.

His mock-heroic poem, La Pucelle, 1730-39, is a travesty of everything sacred: the Henriade, 1728, is in another vein. His correspondence is most voluminous, and universal in its topics. He was the acknowledged head of European literature in his later years, and wielded enormous influence, which he used nobly in defense of freedom, as in the cases of Calas and Sir

ven.

His character was

a strange mixture of virtues and vices: his hatred of priests, of supernaturalism, and apparently of all forms of visible religion, freely displayed in his Dict. philosophique, 1762, and elsewhere, and formulated in the watch

word, Ecrasez l'infame, earned much posthumous no less than contemporary obloquy. He was imprisoned 171617 and 1726, in England 1726-29, at Cirey in Champagne 1734-49, in Russia 1750-53, and at Ferney near Geneva from 1758, till shortly before his death, when he received an almost idolatrous ovation in Paris.

Voltameter. Instrument for measuring the strength of an electric current by means of certain electrolytic effects which it produces. If the current be passed through acidulated water between two platinum electrodes so arranged that the gases resulting from the decomposition of the water are collected and measured, the current strength is proportional

[blocks in formation]

Volterra. Italian town, 35 m. s.w. of Pisa; notable for its Etruscan antiquities. Pop. ab. 7,000.

Volterra, DANIELE DA, 1509-1566. Italian painter, employed to drape the nude figures in Michelangelo's Last Judg ment. His fine fresco of the Descent from the Cross is in Trinitá de' Monti, Rome.

Voltmeter. Instrument for determining the electromotive difference of potential between two points of an electric circuit. The indications are given directly in volts by an in

[graphic]
[graphic]

Thomson's Voltmeter.

dex which moves over an empirically graduated scale. Voltmeters have been devised by Thomson, Ayrton and Perry, Deprez, and Carpentier.

Volume. Limited space in three dimensions, as subject to measurement, or result of such measure. The primary unit of volume is a cube whose edge is a linear unit.

Volumenometer, VOLUMOMETER, or STEREOMETER. Instrument for measuring volumes; e.g., that of an irregular solid. It consists of two glass tubes placed vertically against two scales. The tubes are joined at the bottom by a pipe with a tap in it. One of them is open at the top; the top of the other is bent at right angles, and to it is attached a small spherical flask; at the bottom of this tube is a second tap. The tubes are partly filled with mercury, the height of which may be regulated by the taps at the bottom. The volume of the flask and that of the tube down to a certain mark must first be found, then, by introducing the solid into the flask and repeating the experiment, the volume of the solid is known. This method is appli

[graphic]

Volumenometer.

cable for finding the true volume of the material of a porous substance, as a piece of wood; thus the real density of wood may be found. This instrument may be used also for experimentally verifying the law of Boyle.

Volumetric Analysis. Branch of quantitative chemical analysis, in which the quantity of a constituent present in a compound is found by running in a known amount of some substance, in form of a standardized solution, which will convert the constituent into some other form. The end of the reaction is usually shown by a change in color or the deposition of a precipitate.

Voluntary Conveyance. Transfer of property without a valuable consideration. It may be set aside as fraudulent against creditors of the grantor.

Voluntaryism. Separation of Ch. and State, and support of clergy and services by free-will offerings of their adherents; system prevalent in the U. S., and urged or desired by British

Nonconformists.

Volunteers. Term applied to a portion of the military forces of the U. S. employed during the Civil War; so called

« PreviousContinue »