Slike strani



conquered Gauls. The Torquati, a family of New York. He has published «The House of a Manlian gens, attribute their name to their an- Hundred Lights' (1900); 'El Dorado: a cestor. T. Manlius, who having slain a giant Tragedy (1903); Abelard and Heloise (poGaul in single combat lifted from the neck of etic drama, 1907). the dead body an enormous gold torque, which he ever afterward wore upon his own.

TORRENS, William Erskine, American

promoter : b. New York, 15 July 1870; d. 20 June TORQUEMADA, Juan de, hoo-an' dā

1914. After making a study in the mills of tor-kā-mä'thä (Latinized form TURRECREMATA), New England and Philadelphia of manufacturSpanish theologian and cardinal: b. Valladolid, ing methods and finance, he became in 1896 1388; d. Rome, 26 Sept. 1468. He entered the foreign commissioner for the National AssociaDominican order in 1403, and was graduated tion of Manufacturers of the United States, at the University of Paris in 1424. After serv- and was thus engaged until 1899. During this ing as prior at Valladolid and Toledo, he was time he secured concessions from Brazil, Veneappointed by Eugenius IV master of the sacred zuela, Argentina, Cape Colony, China and palace in 1431. In 1439 he became a cardinal- Japan for establishing sample warehouses for priest, later exchanged his title for the cardinal- the exhibition of American manufactured goods. bishopric of Albano, and still later (1464) for He has written Commercial Traveling in that of Sabina. He gave liberally of labor South America) (1897); (Commercial Traveland money to charities and church-building, ing in South Africa (1898); (Commercial and won fame as a theological writer and con- Traveling in the East' (1899). troversialist. He was an influential member of the councils of Constance, Basel and Flor

TORRENS, Lake, South Australia, a large

shallow salt lake, the central one of a group ence, at the last-named of which drew up the

in the central southern section, 125 miles long proposals for union between the Greek and Latin churches. Among his works may be

and 25 miles wide, about 50 miles north of mentioned Meditationes? (1467); Quæstiones

Spencer's Gulf. In the dry season it is re

duced to a salt marsh. Spiritualis Convivii Delicias præferentes super Evangeliis) (1477); and Commentarii in De- TORRENS SYSTEM, a system of titlecretum Gratiani? (1519). Consult Lederer, Der registration devised by Sir Robert Torrens, spanische Cardinal Johannes von Torquemada? and first successfully used in Australia. Its (1879).

object is to make the transfer of landed propTORQUEMADA, Tomás de, Spanish

erty as simple and as safe as that of any other monk, first Grand Inquisitor of Spain: b. Valla

property and to do away with the necessity of dolid, 1420; d. Avila, 16 Sept. 1498. He en

repeated title examinations. The system is tered the Dominican order, was for 22 years

operated through a bureau of registration, in prior of the monastery at Segovia, and in

charge of a registrar, and becomes effective on October 1483 was made by Sixtus IV inquisi

the first transfer of any property after the estor-general for Castile and Leon. The Inquisi

tablishment of the system, all land transactions tion (q.v.) had been established in 1480 at Se

being registered in this office. A title may be

Beville, but Torquemada was the first to give it

registered as absolute or as possessory. its organization. He founded four tribunals

fore registry the title is fully investigated by at Seville, Cordova, Jaen and Villa Real. Dur

the registrar, who receives from the owner all ing his 18 years of office he burned 10,220 per

the documentary evidences of title, descriptions

of boundaries, etc. When the registrar is satsons and condemned 6,860 to be burned in effigy. By these methods the Inquisition acquired vast

isfied that the title is perfect, he files away all sums of money. Torquemada was justly hated,

these old papers and issues to the holder a cerand never went about without a body guard.

tificate of ownership, a duplicate of which is His later activities were directed against the

filed in the registrar's office. Such certificates Jews and about 1,000,000 of them fled the

bear on their faces notice of all encumbrances country to escape his persecution. He was

on the property. If the estate is vested in fee one of the most bloodthirsty fanatics of his

simple the title is known as "absolute and the tory. Consult standard works on the history

certificate is stated to be an absolute certifiof Spain and of the Inquisition; also Molènes,

cate. Should it appear that an absolute title Document Inéditis. Torquemada et l'Inquisi

to any land can be held only for a limited tion (1897).

period or subject to reversions, then the regis

trar will except from the effect of registraTORRE DEL GRECO, tör'ně děl grā’ko, tion any estate, right or interest arising before Italy, on the Bay of Naples, seven miles south

the specified date or under the conditions east of Naples at the foot of Vesuvius. The

named, all of which will be entered in the town has been demolished by earthquake at register and noted on the certificate, which various epochs, and in 1857 and 1906 a simi

is stated to be a "qualified certificate. In lar disaster greatly changed and damaged the

the case of a “possessory» title the applicant is locality. It is much frequented by foreigners

registered as becoming owner on giving such as well as Italians on account of its sea

evidence of title as may be prescribed, and the bathing. There are important coral and other registration of any person as first owner with fisheries, besides shipyards, manufactories of

a possessory title only will not interfere with rope, coral goods and lava ware. Pop. of

the enforcement of any estate, right or interest commune about 36,000.

adverse to the title that may then exist or TORRENCE, Frederic Ridgely, American which may arise a later date. And this fact poet: b. Xenia, Ohio, 27 Nov. 1875. He was is noted on the possessory») certificate issued educated at Miami, Ohio and Princeton uni- to the owner. This examination and registraversities, was librarian in the Astor Library tion of title does not have to be repeated after 1897–1901, and since 1901 at the Lenox Library, a certificate has once been issued, the transfer

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of the certificate with accompanying entry of TORRENTS OF SPRING (“Véshniya that fact in the registrar's office completes the Vódui?), by Iván Sergéyevitch Turgénief, is transaction. By this method the transfer of the tragi-comedy of a man of weak will who a land title certificate becomes as simple and as succumbs to a passionate impulse, yields to the inexpensive as the transfer of a certificate of seductions of the typical «vampire woman and stock or of a bank share, and the holder of throws away the happiness of his whole life. the title is absolutely free from the usual "Weak men,” says the author, «never bring danger of land title transfers, such as flaws things to an end; they always wait for the in the title, the neglect of obscure future con- end to come.” The title is symbolical and not ditions, etc. Should any person suffer loss quite adequate, the comparison being introduced through misdescription, omission or any other in the wrong place. error in the certificate issued by the registrar, Sánin, a young nobleman, is in his 22d year, he is indemnified from an insurance fund cre- very good-looking, with handsome graceful ated for that purpose. This fund is provided figure, kindly bluish eyes, golden hair, a clear by the imposition of a tax of one-fourth of skin, a smile like a child's and giving the im1 per cent on the value of the land at the

pression of “freshness, health and softness, time of the first certificate of title being softness, softness, a man (recognizable at a granted, in addition to the registration fees. glance as the son of a sedate aristocratic family, The registrar is the judge in all cases as to the type of the fine young pomyeshchik, born and the liability of the fund to such compensation. reared in our wide steppe-like regions. On The fees for registration under the Torrens sys- his way home from Europe to Russia he is detem are very small, usually being $24 in case of tained for a few hours at Frankfurt-am-Main, the first registration, and three dollars upon and by chance drops into a confectioner's shop the issue of every subsequent certificate. The conducted by the widow of an Italian Revolusystem has been vigorously opposed by title tionist. It happened that just at that moment guaranty companies and by members of the Emilio the only son had fainted and his sister, legal profession who see in it an end to a Gemma, a young girl of exquisite beauty apfruitful source of fees since under it there is peals to Sánin to bring him back to life. This furnished State title insurance instead of pri- the young man does; the family are profuse in vate title insurance, with nominal cost for con- their expressions of gratitude and persuade veyances.

him to remain for a few days in Frankfurt. The Torrens system is in use in South Aus- During a Sunday excursion with the two tralia (1858), British Honduras (1858), Van- young people and Grüber, a bumptious and couver (1860), consolidated with British Co- conceited German clerk to whom Gemma is lumbia (1866), Queensland (1861), Tasmania betrothed, an intoxicated officer, Baron von (1862), New South Wales (1862), Victoria Dönhof, insults the young girl, and when her (1862), England (1862, 1875, 1897), Ireland lover shows no spirit to resent it, Sánin impul(1865, 1891), New Zealand (1870), British Co- sively takes it upon himself to provoke the inlumbia (1871), Western Australia (1874), evitable duel. This duel is described at conWales (1875, 1897), Fiji (1876), British Guiana siderable length with a wealth of comic detail. (1880), Ontario (1885), Manitoba (1885), Neither party is injured and the Russian and Canadian Northwest Territories (1886), Lee- the Baron part almost friends. ward Islands (1886), Jamaica (1888), British It results, however, in Gemma's breaking New Guinea (1889), Cyprus (1890), Illinois her engagement with the ridiculous and pusil(1895), Ohio (1896), California (1897), Massa- lanimous Grüber, but Signora Roselli begs chusetts (1898), Minnesota (1901), Oregon Sánin to use his influence with her daughter (1901), Philippine Islands (1902), Colorado to persuade her not to ruin her prospects and (1903), Hawaii (1903), Nova Scotia (1904), reputation by such an act, an engagement being Alberta (1906), Saskatchewan (1906), Wash- regarded in Germany as no less sacred than ington (1907), New York (1908), North Caro- marriage itself. Sánin reluctantly undertakes lina (1913), Mississippi (1914). The Massa- to fulfil this delicate mission but finds it imchusetts law is the best and the most success- possible, since he has himself fallen in love ful in the United States; the New York law with the beautiful girl and she is no less fashas been in great part a failure, due to de- cinated with him. He decides to sell his estate fects in the act, of which the opponents of the in Russia and invest money in the widow's consystem have taken advantage. Since the origi- fectionary business. By another turn of fate nal Torrens Act gave a judicial and discre- he meets at this moment his former schooltionary power to the registrar not in conform- mate, Pólozof, another type of the lazy, easyity, with the spirit of American institutions, going Russian, who is married to an this portion of the law has been slightly mously rich young woman. Pólozof tells Sánin changed in order to adapt it to the require- that his wife will perhaps buy his estate and ments of this country. Consult Niblack, offers him a place in his carriage to Wiesbaden William, Analysis of the Torrens System where Márya Nikolayevna is taking a cure. (Chicago 1912); Cameron, A. G., «The Torrens She is beautiful but unscrupulous and plays all System (Boston 1915); id., The Torrens her arts to fascinate Sánin, who weakly yields System, Its Cost and Complexity; a legal and and never returns to Gemma. Thirty years Practical Treatise! (Chicago 1903); Torrens, later Sánin, always unhappy in his remorse for Sir Robert, Essay on the Transfer of Land his dastardly behavior finds a little garnet cross by Registration (London); Beers, W. F., which Gemma had given him. It brings up (The Torrens System of Realty Titles? (New all the details of his soul's tragedy. He goes York 1907); Kennedy, J. P., List of Ref- to Frankfurt and through Baron von Dönhof erences on the Torrens System) (Virgina State learns that Gemma had married a rich AmeriLibrary, Richmond, Va., 1906).

He writes to her and when she replies,





enclosing a photograph of her own daughter, (1900–01), editor Journal of the American he sees in the picture the very image of his Oriental Society (1900–07; 1911-16) and presilost love and sends her the garnet cross to- dent of the society (1917-18). His publications gether with a magnificent string of pearls. include "The Commercial-Theological Terms Gemma is the very ideal of sweet girlish purity in the Koran” (1892); Composition and His. and charm and is presented in striking con- torical Value of Ezra-Nehemiah' (1896); (The trast with the fascinating and not unsym- Mohammedan Conquest of Egypt and North pathetic Russian siren who ruins men for her Africa? (trans. from the Arabic, 1901); (Selecselfish amusement. It is an amusing and yet tions from Bokhari? (1906); Notes on the rather repulsive story. Originally published in Aramaic past of Daniel) (1909); Ezra Studies the European Messenger (Vyestnik Yevropui) (1910); Composition and Date of the Arts in 1872, it has been translated as "The Torrents (1916). Since 1900 he has been attached to of Spring) by Constance Garnett (1897); Yale College. (Spring Freshets) by Isabel F. Hapgood (New

TORREY, Charles Turner, American York 1904); (Spring Floods) by S. M. Butts

anti-slavery reformer: b. Scituate, Mass., 21 (1874–75), and by E. Richter (London 1896). Nov. 1813; d. Baltimore, Md., 9 May 1846. He

NATHAN HASKELL DOLE. was graduated at Yale in 1830, entered the ConTORRES NAHARRO, B. de., Spanish gregational ministry, and held pastorates at dramatic poet: b. near Badajoz, about 1500. Princeton, N. J., and Salem, Mass. Having reHe is called the creator of Spanish comedy moved to Maryland to promote the cause of and was the first writer of his time to develop anti-slavery, he became an active agent of the fully his plots. He wrote fluently in both Underground Railroad (q.v.), and was arrested poetry and prose and his collected works were and imprisoned in 1843 for his report of a dedicated to Ferdinand d'Avalos, the husband slaveholders' convention held in Baltimore. of Vittoria Colonna. It was not until 1520, The following year he was again arrested, and however, that his plays became known in Spain being convicted of aiding in the escape of runwhere they were very popular.

away slaves, he was sentenced to a long term TORRES (tõr'rěs) STRAIT, the narrow

in the penitentiary. The harsh treatment he channel which separates Australia and Papua.

received while undergoing his sentence brought From Cape York on the northern coast of

on consumption from which he died, and his Australia to New Guinea it measures about 80

remains were taken to Boston where he was miles. Navigation is unsafe owing to the

honored by a public funeral. He was regarded shoals, islands and reefs within its waters. It

as a martyr in the cause of abolition, and «Torwas discovered in 1606 by a Spanish navigator

rey's blood crieth out," became an anti-slavery from Peru.

watchword. He wrote A Memoir of William TORRES VEDRAS, tõr'rės vā'dräs, Por

R. Saxton (1838), and while in prison pro

duced a volume of sketches of Massachusetts tugal, a town in the district of Lisbon, situated

life, Stone, or the Pilgrim's Faith Revived' on the railroad, 25 miles north of Lisbon. It is noted for its extensive lines of fortifications,

(1846). Consult Lovejoy, Memoir of the 28 miles long, reaching to the Tagus River, and

Martyr Torrey) (1847). protecting 500 square miles of territory. They TORREY, John, American botanist: b. were begun in 1809, and behind them Welling

New York, 15 Aug. 1796; d. there, 10 March ton in 1810 checked the French advance toward

1873. He received his first instruction in botany, Lisbon. It has hot sulphur baths and an old mineralogy and chemistry from Amos Eaton, Moorish citadel. Pop. about 8,000.

and was graduated at the New York College of

Physicians and Surgeons in 1818. His leisure TORREY, tõr'i, Bradford, American nat

from medical practice he devoted to scientific uralist and author: b. Weymouth, Mass., 9 Oct.

pursuits, particularly to botany, and in 1824 he 1843; d. 1912. He was educated in the public

abandoned medicine and became professor of schools, taught two years, entered business in

chemistry, mineralogy and geology at West Boston, and for many years after 1886 was a

Point. From 1827 to 1855 he was professor of member of the editorial staff of the Youth's

chemistry and botany at the College of PhysiCompanion. He has been well ranked as a

cians and Surgeons, serving simultaneously at field ornithologist, and writes entertainingly of

Princeton. From 1853 until his death he was his observations. His essays have been collected

chief assayer in the United States Assay Office, into the following volumes: Birds in the

New York. He participated in the councils of Bush? (1885); (The Foot-Path Way) (1892); Columbia College as trustee, and in 1860 preA Florida Sketch-Book (1894); Spring sented to that institution his extensive herNotes from Tennessee); A world of Green

barium and botanical library. In his special Hills) (1898); Every-Day Birds). (1900); field of scientific research his publications were Nature's Invitation? (1904); Friends on the

numerous. One of his earliest was a CataShelf? (1906); Field Days in California' logue of Plants Growing Spontaneously Within (1913).

Thirty Miles of the City of New York (1819), TORREY, Charles Cutler, American Se- which he prepared for the New York Lyceum mitic scholar: b. East Hardwick, Vt., 20 Dec. of Natural History (now the New York Acad1863. He was educated at Bowdoin College emy of Science), of which he was a founder where he taught Latin (1885-86). He studied and for many years president. In 1843, as at Andover Theological Seminary (1886–89) botanist of the Geological Survey of New York, and at the University of Strassburg (1889-92) he published an elaborate work on the flora of where he took his Ph.D. degree. Since that that State. Meantime he had issued in connectime he has been instructor in Semitic languages tion with Asa Gray (q.v.), parts of a work on at Andover (1892–1900), director of the Ameri- (The Flora of North America'; but this was can School of Oriental Research in Palestine also discontinued after the completion of the

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order Compositæ. From 1845 onward he pub- was originated and developed by members of lished memoirs and reports on the botanical this society. The club issues three regular pubspecimens brought back by expeditions to vari- lications, namely: Bulletin, a very scientific and ous parts of the West and South by Capt. John widely known journal; Torreya, of more popuC. Fremont and others, among them being re- lar scope; and Memoirs, which include many ports on the botany of the expeditions for as- valuable monographs. certaining the most practicable route for a TORRICELLI, tor-re-chěl'lē, Evangelista, Pacific railroad and making the Mexican Italian mathematician and scientist : b. Faenza, boundary survey. He was president of the Italy, 1608; d. Florence, October 1647. He early American Association for the Advancement of

devoted himself to mathematical studies, and Science in 1855, and was named by Congress in having read Galileo's Dialogues, composed a 1863 one of the original members of the Na

treatise concerning motion according to his tional Academy of Sciences.

principles. Galileo having seen this, conceived TORREY, Joseph, American clergyman: a high opinion of the author, and engaged him b. Rowley, Mass., 2 Feb. 1797; d. Burlington, as his amanuensis. He accordingly, went to Vt., 26 Nov. 1867. He was graduated at Dart- Florence in October 1641, but Galileo dying mouth in 1816 and at Andover Theological three months after, Torricelli was about to reSeminary in 1819. He was for a time pastor turn to Rome, when the grand duke of Tuscany, of a Congregational church at Royalton, Vt., Ferdinand II, engaged him to continue at Florbut in 1827 became professor of Greek and ence, giving him the title of ducal mathematiLatin at the University of Vermont. In 1842 cian and the promise of a professorship in the he took the chair of philosophy there, and in university on the first vacancy. Torricelli's 1862-66 was president of the institution. He name is important in the history of science as translated Neander's General History of the the discoverer of the natural law according to Christian Religion and Church? (1854), and which fluids rise in an exhausted tube from an edited Remains of President James Marsh open vessel exposed to the pressure of the at(1843), and Select Sermons of President mosphere, namely, that the weight of the fluid Worthington Smith (1861). A volume of his which rises in the tube is equal to the weight lectures, A Theory of Fine Art,' appeared of an equal surface of atmospheric air of the posthumously (1874).

height of the atmosphere. He also improved TORREY, Reuben Archer, American

the telescope and microscope. See BAROMETER. evangelist: b. Hoboken, N. J., 28 Jan. 1856. TORRICELLIAN EXPERIMENT, The, He was educated at Yale College and at Leipzig so called because made by the Italian physicist, and Erlangen in Germany He was ordained Evangelista Torricelli (q.v.), who discovered as a Congregational minister in 1878, was super- the principle upon which barometers are made. intendent Minneapolis City Mission Society and Torricelli was led to investigate Galileo's theobecame associated with Dwight L. Moody in ries of the law that "nature abhors a vacuum.” 1889 and served as superintendent of the He filled a glass tube, closed at one end, with Moody Bible Institute until 1908. In 1902-03 mercury, and placing his finger over the open he made an evangelistic tour of the world. end inverted the tube. He now placed the tube His life has been devoted to evangelistic work vertically in a small trough containing mercury in many lands and he has written much on and removed his thumb from the open end, Bible subjects which have been translated in a after it was under the surface of the mercury score of languages.

The mercury in the tube dropped until it stood TORREY BOTANICAL CLUB, a bo

at a height of about 30 inches. Here it rested, tanical society in New York which is the most

with a vacuum in the top of the tube, under the important organization of its kind in America,

closed end. Torricelli concluded that the coland one of the six scientific societies affiliated in

umn of mercury in the tube was sustained by the Scientific Alliance. The club was an out

the pressure of the atmosphere on the larger growth of a former club, chartered in 1871.

surface of the mercury in the trough and that This band met in the herbarium of Columbia

the height of the column was in inverse ratio to College, "drawn there by the genial welcome

its specific gravity. Other experiments conand wide botanical knowedge of its presiding

firmed this theory and led to the invention of spirit, Dr. (John) Torrey," and was the nucleus

the barometer (q.v.). of the present club, finally organized_under its TORRIGIANO, Pietro, pe-a’trõ tór-represent name, complimentary to Dr. Torrey, in jä'nā, Italian sculptor: b. about

1470; d. Spain, 1873. Dr. Torrey was the first president, but,

1522. He went to England in 1509 to erect the unfortunately, died almost immediately.

tomb of Henry VII and his queen, still in WestThe Torrey Club is the centre of botanical minster Abbey. The works which he executed interest in New York, and the neighborhood, for English churches were destroyed by the and is especially valuable for its weekly ex- Puritans. He was given a commission to make cursions that may be joined by any botanist,

a statue of the Virgin Mary, and receiving what and which take parties out to good botanizing

he considered an inadequate price destroyed it. localities under intelligent guidance. Many

For this he was imprisoned by the Inquisition, local floras have been compiled by members of

and there starved to death. the club, one of the most important of which TORRINGTON, Frederick Herbert, Cais that of Dr. Britton and others, (The Pre- nadian musician: b. Dudley, England, 20 Oct. liminary Catalogue of Anthophyta and Pterido- 1837, and was educated there. When but 16 phyta growing within 100 miles of New York.) years of age he was made organist (1853) at The valuable herbarium of the club includes the Saint Anne's Church at Bewdley, England, and material for this list, and specimens of the in 1857-69 he held a similar position at Great flora, within the same area. It is now depos- Saint James Street Methodist Church, Monited at the New York Botanical Garden, which treal, Canada. He then went to Boston where



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which can also be charged. The reading of the graduated head being observed when the fibre is fre from torsion and the balls, g g', are at a known distance from each other, the balls are charged. They at once separate, owing to the repulsive action exerted between two electrical charges of the same sign. The graduated head is then turned so as to produce a torsion on the suspending fibre, tending to restore the balls to their original position. The twisting of the head is continued until the relation of the balls is the same as at first; and when this state is established, it is evident that the torsion of the fibre is exactly balanced by the repulsion of the charges. In order to deduce the electrical repulsion in definite measure, it is only necessary to determine, by a separate experiment, what force is required to twist the suspending fibre

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he was organist in Kings Chapel (1869–73) and professor in the New England Conservatory of Music. Returning to Canada he became organist of the Metropolitan Church at Toronto and conducted the Philharmonic Society there and founded (1886) the first Toronto musical festival. Two years later (1888) he founded the first college of music. He was elected president of the Canadian Society of Music in 1892. In 1895 and 1896 he conducted musical festivals at Toronto and in 1903 was assistant conductor of the cycle of musical festivals in that city.

TORRINGTON, tõr'ing-tón, Conn., borough in Litchfield County, on the Naugatuck River, and on the New York, New Haven and Hartford railroads, about 23 miles west of Hartford and 18 miles north of Waterbury. Settlements were made in the vicinity in the early part of the 18th century, and in 1740 Torrington was incorporated. In 1887 it was hartered as a borough. It is the birthplace of John Brown (q.v.). The borough has a number of manufacturing establishments; chief among which are bicycle and machine shops, plating-works, brass-works, woolen mills and novelty works. It also manufactures needles, hardware and tobacco products. In 1914 there were 54 manufacturing establishments, with a capital of over $16,000,000, and annual products of over $14,000,000, with payrolls of about $2,500,000. The principal public buildings are the churches, schools and the Young Men's Christian Association building. The educational institutions are a high school, public and parish schools, several private schools and a public library. There are two banks. The borough is the commercial and industrial centre of the town of Torrington, which contains 20,623 inhabitants.

TORSION BALANCE, an instrument in which small forces are measured by noting the torsion that they can produce in a fine wire or a delicate fibre of some other material. The invention of the instrument is usually ascribed to Coulomb (1736–1806), who employed it in his extensive researches on electricity. Cavendish also made use of it for the purpose of determining the mass of the earth; his experiment consisting in determining the attractive power of a pair of leaden spheres, and comparing this with the attractive power of the earth itself. In its conventional form, the torsion balance consists of a light horizontal arm, suspended at the centre by the fibre whose torsion is to measure the force that is applied to the arm. Quartz is now extensively used for the suspending fibre, its employment having been suggested by C. V. Boys, who showed how to prepare fibres of this material, which are very strong and elastic. Boys dipped an arrow into melted quartz and then shot the arrow from a bow; the quartz being thereby drawn out into a fibre of exceeding fineness. The upper end of the torsion fibre is attached to a graduated head, by whose rotation the fibre can be twisted through a known angle. In applying the torsion balance to the measurement of electrical repulsions, the horizontal arm, f, is provided at one end with a light ball, g, which can be charged to a definite electrical potential, and the torsion head is turned so that this ball is brought to a known distance from a similar fixed ball, g',




Torsion Balance. through one entire turn; and a simple proportion then gives the repulsive force desired. The application of the torsion balance to experimental work of other kinds will be readily understood from the foregoing description of its application to the measurement of electrical repulsions; for the principles involved are the same in all cases, the force that is to be measured being determined by noting the torsion required to neutralize it, in a fibre whose torsional constant has been determined by direct comparison with a known force. The fact that the torsional moment of a homogeneous twisted fibre is proportional to the angle through which the fibre is twisted was established experimentally by Coulomb. In actual service the torsion balance is surmounted by a case of metal or glass, the air in which is kept dry by a dish containing calcium chloride, or phosphorus pentoxide or pumice stone wetted with concentrated sulphuric acid or some other powerful and non-volatile drying agent.

The name torsion balance) has also been applied to a form of commercial balance in which the pans that contain the weights and the objects to be weighed are supported, not upon knife edges, but upon the middle points of narrow, thin, horizontal ribbons of stretched steel, in such a manner that when the balance de

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