THIGMOTROPISM. 229 THIRTY TYRANTS. ness of organisms to stimuli by contact, especial- ly to prolonged contact with solid substances. The responses in plants depend chiefly upon a modification of the growth of the organs con- cerned. It is especially marked in tendrils. Other examples are to be found in the similar curvatures of the petioles of leaf climbers, and in the stems of dodder. See Growth. THIL'LY, Frank (1865—). An American educator. Iiorn in Cincinnati, Ohio. He gradu- ated at the university of his native city in 1887, and then studied for two years at the University of Berlin, and for two more at Heidelberg. In 1892-93 he was an instructor of logic and the history of philosophy in the Sage School of Phi- losophy at Cornell University. In 1893 he was appointed professor of philosophy at the Univer- sity of ilissouri. His publications include: Leibnitz's Controversy ivUh Locke (1891); .Ik Introduction to Ethics (1900) ; and translations of Frederick Paulsen's Einleitung in die Philoso- phie (1895) and Weber's History of Philosophy (1896). THIONVILLE, te'oN'vel'. See Dieden- HOFEX. THIOSULPHURIC ACID (from Gk. eriov, theion. sulphur -I- Kng. sulphuric) , HjS^Oj, less properly 'hyposulphurous acid.' An acid com- pound unknown in the isolated state and but little known in the form of dilute aqueous solu- tions, but well known in the form of its salts, called thiosulphates (or hyposulphites I , espe- cially its sodium salt. The thiosulphates are formed by the action of metals (such as zinc, iron, etc.) on acid sulphites. The thiosulphates of the alkalies are freely soluble in water ; those of the alkaline earths are much less soluble ; while those of the heavy metals are by them- selves insoluble, but generally form soluble double compounds with the thiosulphates of the alkalies. The thiosulphate of sodium may be prepared in the laboratory by boiling a solution of sodium sulphite with sulphur. It may also be made from the thiosulphate of calcium. The latter is produced by the action of sulphur on lime. Hence it is produced (along with calcium pentasulphide) when lime is used for the puri- fication of illuminating gas. Further, it is formed when a solution of calcium pentasulphide is exposed to the oxidizing action of the air — a reaction causing the production of the thiosul- phate in the manufacture of soda (q.v. ) and its increased production in the purification of il- luminating gas. Aqueous sodium thiosulphate has the remarkable property of dissolving the halogen salts of silver, mercurous chloride (calo- mel ) and iodide, the iodide and the sulphate of lead, the sulphate of calcium, and the oxides of copper. Owing to its capacity for dissolving the halogen salts of silver unaltered by light, it is extensively used in photography. It is further employed in the manufacture of certain coal- tar colors and in dyeing. THIRD. See Ixterv.i,. THIRD ESTATE (Fr. tiers fiat). See States General; France; French Revolu- tion. THIRL'WALL, N^ewell Connop (1797- 1875). An English historian and bishop. He was born in London. He studied at Charter- housB School and graduated at Triiiitv College, Cambridge, in 1818. In 1820 he entered Lin- coln's Inn and was called to the bar in 1825, but the profession of the law was distasteful and he spent the intervening years until 1828 in travel and literarj pursuits, publishing translations of tales from Tieck and Schleiernuicher's ('ritinil Essay on the CoxjkI of Ht. Luke (1825). In 1827 he took up his residence in Cambridge, and until 1834 he held various otlices in the university, when he was called upon to resign his appoint- ment as assistant tutor on account of, a pamphlet, Letter on the Admission of Dissenters to Aea- demical Degrees. He accei)ted a living at Kirby Underdale in Yorkshire, where he wrote his Uis- tory of Greece (1835-44). In 1840 he waa appointed bishop at Saint David's in Wales; in 1874 he resigned his see and retired to Bath, where he died. ' With J. C. Hare he translated yiebuhr's Historij of Rome (1828-32). His Re- mains, Literary and Theological, and Essays, Speeches, and Sermons were edited by J. .J. S. Perowne (London, 1877-80) ; his Letter to a Friend, with a memorial sermon, was edited by Dean Stanley (ib., 1882), and his Letters, Literani and Theological, by Perowne and Stokes (ib.. IS'SI). THIRST (AS. pvrst, pyrst, Goth, paiirstei, OHG. durst, Ger. Durst, thirst; connected with Lat. torrere, to parch, Gk. Tepatadai, tersosthai, to become dry, Skt. tar.?, to thirst). A sensa- tion normally due to a lack of water in the tis- sues of the body. Although the sensation of thirst is referred principally to the mouth and throat, it is not a purely local feeling and can be satisfied by the introduction of fluid into the circulation through various channels. Water maj' be absorbed and thirst relieved by transfu- sion of saline solution into the veins, by injection into the tissues ( hypodermoclysis ) , and to a less extent by absorption from the skin, as well as by drinking. In a state of thirst, the body fluids become reduced in volume, and of higher specific gravity and more saline, and these conditions sufficiently explain the craving for water. Thirst is occasioned physiologically by profuse perspira- tion from exercise — especially in a warm, dry atmosphere — by a highly seasoned diet, or by salty food. Many morbid conditions give rise to thirst; it is always an accompaniment of fevers and inflammations; diseases which, like cholera asiatica, diabetes, and diarrhoea, are characterized by a great loss of fluid from the body, are productive of thirst. Loss of blood produces a great craving for liquids. As an ex- ception to the rule that fevers demand drink, it may be noted that in typhoid fever thirst is sometimes blunted or suppressed. Thirst is most effectively relieved by slightly acidulated drinks, since these provoke an outflow of saliva. In fevers, cracked ice, effervescing drinks, and fruit juices are grateful and help to reduce the temperature. THIRTY-NINE ARTICLES OF RELI- GION, The. See Articles, The Thirty-Nine. THIRTY TYRANTS. A body of rulers in Athens, invested with sovereign power after the close of the Peloponnesian War. B.C. 404. They were all native Athenians, but members of the aristocratic party, and chosen by the Spartan conquerors, who. knowing the animosity existing between the democracy and the oligarchy
