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TESTING MACHINE—TETRABRANCIII ATA
Testing Machine. Apparatus by which known or measurable stresses can be applied to specimens of materials or members of structures, for ascertaining experimentally their resistance to such strains. The usual types of machine are to apply tests in tension, in compression, in flexure, or in torsion. One type can usually make the first three investigations; torsion requires a special but inexpensive machine for the best work. The older testing machines loaded a pan with direct weights and multiplied their effect by levers which applied the multiplied load to the specimen; recent ones use either the hydraulic press or screw searing to produce the load upon the specimen, that load passing through the sample and being balanced by counterpoises upon a graduated scale beam. The counterweights on the scale beam can thus be regarded as applying the load through the multiplying levers as before, the
strain gearing being used only to neutralize deformation as it occurs. There are therefore two types of testing machine with respect to the applying of strain, hydraulic and screw. The hydraulic machines have the advantages of working easily by hand and rapidly, and of easy release of load for determining elastic limit; they are not so well adsrted to keep specimens under prolonged strain. The screw machines are adapted for use by power, with slow and gradual increase of strain and its prolonged maintenance. The torsional machines twist the prepared specimen by worm gear, and record the strain by the deflection of a loaded pendulum. The best machines give an autographic record of the test of specimens, a tracing point usually indicating elongations as abscissas upon the loads as ordinates. The largest machines are of the hydraulic type. The most perfect one ever built is the Emery Machine (q.v.). The most powerful machine is that at Phoenixville, Pa.; its capacity is 2,160,000 lbs., and it can break a bar 45 ft. long.
Testis (testicle). Essential reproductive gland of a male animal; in it, the spermatozoa are developed. In its most perfect condition of development a testis consists of a number of chambers or lobules, in each of which lie several coiled tubules (in Man, ab.800 each 2 ft. long). In the walls of the tubules the spermatozoa are formed by multiplication and transformation of epithelial cells. The tubules empty by means of a few straight tubes into a network of tubes from which in Man there are ab. a dozen vasa efferentia uniting to form the vas deferens or sperm duct. The latter in Man is ab. 20 ft. in length coiled up into an epididymis, and thence passing by a length of 2 ft. to reach the urethra. Testes are always paired and are developed and originate in the body cavity in a position corresponding to that of the ovaries, i.e., near the kidneys. In most Mammals they slip backward through the inguinal canal into scrotal sacs of the skin at the external opening of the urino-genital sinus. In the elephant, most Edentates, and lower among Mammals and all other Vertebrates, they never leave their primitive position. In Rodents and Inseetivora they descend through the inguinal canals only during rutting.
Test Oath. Generally, affirmation of present loyalty to a government. If so imposed as to be ex post facto in effect, it is unconstitutional in the U. S.
Tcstudlnata. Broadly, all the Chelonia (q.v.); in a restricted sense, the Testudinidce.
Tcstudinida?, or Chersidvb. Land Tortoises, a family of Chelonia. having high arched carapace, under which the head and feet can be retracted. The feet have separate
toes, and are adapted for walking. They are strictly herbivorous. The Emydidce are, by some, included as a subfamily. Examples of the family are the large and strong Gopher-tortoises of the Carolinas, which burrow in the earth, the massive Amazon Tortoise, used for food by the natives, the Galapagos Tortoise, and the small Garden Tortoise of Europe, also used as food.
Tetanus. Disease characterized by the continuous spasmodic contraction of certain muscles. Frequently the muscles of the jaws; whence the common name, lock-jaw. The origin is now traced to the presence of a specific microbe: the bacillus of tetanus. It usually is associated with an infected punctured wound, as the puncture of a rusty nail. It is one of the diseases where serum therapy seems to be curative, the results of the injection of tetanus antitoxin being very satisfactory as far as there has been opportunity to use it. Prevention is" far better than to risk the employment of the remedy, hence every punctured wound should be enlarged by a free incision to give an opportunity to properly cleanse the wound. If this is done promptly and thoroughly, tetanus will not ensue. Tetanus should not be confounded with tetany, which is also a disease of tonic spasm, but not so serious in its manifestation, nor is it due to an infection.
Tethya. See Tetractinelud^e.
Tetllj'Oldea (ascidians). Mostly fixed Tunicata, with saccular bodies. The inhalent and exhalent pores are close together; the branchial sac is large. Development is through a tailed-larva stage. There are four orders: Copelatoe. Ascidice simplices, Ascidice composite/;, and Ascidice salpoefortties. The first order may be grouped as Perennichordata, the others as Caducichordata. See Ascidians.
Tethys. Daughter of Uranus and Gaea; wife of Oceanus; mother of the ocean-nymphs and river-gods.
Tetraammonlum Compounds. Formed by the union of a tri-substituted ammonia with the halogen compound of an organic group. They may be regarded as ammonium salts; thus trimethylamine, (CH,),N, + methyl iodide, CH,I, — tetramethylammonium iodide, (CHa^NI.
Tetrabaslc Acid. See Acid.
Tetraoorfc Acid. HsB,0,. Pyroboric acid; brittle, glass-like substance, obtained by heating boric acid to 160° C. Its principal salt is borax, sodium tetraborate.
Tetrabranchlata. Cephalopoda with four gills, with a cleft funnel, and a many-chambered shell. The anterior chamber contains the animal; the others are united by a central siphuncle and contain air. Nautilus has 19 external tentacles (the dorsal pair can close the orifice of the shell), 2 ocular tentacles near each eye, and 12 internal tentacles, the four ventral of which, on left side, form the spadix; in the female
much folded. Orthoceras. of structure allied to Nautilus but with a straight (not spiral) shell, is also fossil.
Tetrabromfluorescetn. See Eosin.
Tetrachlornaphtlialene. Cl0H8Cl4. Naphthalene tetrachloride; nipt. 182* C; solid, prepared by the action of chlorine or chlorate of potash and hydrochloric acid upon naphthalene; used in the manufacture of phthalic acid.
Tetracbord. System of four tones, which were the basis of the ancient Greek scales. It always compassed the interval of a fourth, but the middle tones were variable.
Tetracoralla. See Rugosa.
Tetractiliellidrc. Order of Plethospongice, including marine sponges with a more or less horny skeleton, inclosing a variable number of tetraxial spicules of flint: similar spicules are scattered freely throughout the sponge flesh. Other forms of spicules are present, but the prevailing form consists of a long ray bearing three short axes at one end. Geodia and Tethya are examples.
Tetrad. In Biology, group of four cells regularly placed in a square, resulting from a twice repeated binary division effected in vertically crossed planes.—In Botany, (1) four cells produced in the development of pollen grains from the mothercells; (2) group of four chromosomes, formed in the primary egg-cell or pollen-cell preparatory to cell-division.
Tctrudyniite. Mineral compound of bismuth and tellurium, found in the gold regions of Va., N. C, and Ga.
Tetradynamia. Linnaean class of plants, comprising those having four longer and two shorter stamens, as in Cress, Mustard, Turnip, and Pepper-grass.
Tetragram. In Modern Geometry, complete quadrilateral; figure formed by four straight lines, no three of which are concurrent.
Tetragrammaton. Sacred quadriliteral name of God, J-h-v-h (Jehovah), which the Jews hold it unlawful to pronounce, substituting Adonai, Lord.
Tctrngynla. Orders of plants having four pistils.
Tetralicdrite. Cu6Sb.,S7. Mineral copper sulphantimonite, in which the copper is often replaced in part by iron, silver, zinc, and mercury, and the antimony by arsenic; valuable as an ore of copper and, in the argentiferous varieties, of silver.
Tetrahedron. Polyhedron of four faces, necessarily triangles.
Tetralogy. Series of four plays or other writings.
Tetramera (psetootetramera, or Cryptopentamera). Colcoptera, with apparently four-jointed tarsus, but also an extra rudimentary joint. Here belong the Bostrychidoz, species of which injure pine trees by boring in the wood: the weevils (Curculionidce), which have a proboscis, and whose larvas live
of the Madder family, the common Plantain, Dogwood, and Holly.
Tetraonida?. Family of Gallinacei, having a stout body, with short neck, small feathered head, and short legs, usually feathered to the toes. Partridges and Grouse are examples. The latter are larger, with nostrils feathered, and usually a naked strip over the eye.
Tetrapetalous. Corolla consisting of four petals.
Tetraphyllous. Plant bearing four leaves, or calyx or corolla composed of four leaves (sepals or petals).
Tctrapleura. Zygopleural organisms with four antimeres, according to the promorphology of Haeckel. The Annelids are examples.
Tctrapneumona. Holothurians with flask-shaped bodies, at whose narrow end are both the mouth and anus. The in
Tetrapneumooa: a. Ypsiluthuria atttnuata; b, RUopalodina neurtali.
testine has four gill-caeca. Ten tentacles are present, and five sets of double rows of ambulacral feet. Rhopalodina is an example. See Apoda.
Tctrapneumoiies (terretellarle). See Araneida and Spiders.
Tetrapolitan Confession. Prepared by Bucer and Capito in the Reformed interest; adopted by four cities, Strasburg, Constance. Lindau, and Memmingen; presented to the Diet of Augsburg July 11, 1530, but not read there, nor further accepted.
Tetraprionidian. Graptolites with four rows of hydrothecse arranged down the stem of the polypary.
Tetruquetrous. In Botany, sharply four-angled; chiefly stems.
Tetrarch. Ruler of a fourth part; Galatian title, transferred by the Romans to Palestinian princes, as Herod Antipas, whom they were not willing to call king. The distinction was not much observed by their subjects. See Matt. xiv. 1, 9.
Tetrascpaious. Calyx composed of four sepals, as in St. John's Wort.
Tetraspores. Bright red spores formed by quadrate celldivision in many of the Florideae or red Algce. These are rarely in twos or eights, but ordinarily in fours; they propagate the plants independently of any sexual process.
Tetrastf choug. Arranged on the stem in four longitudinal rows.
Tetrastigm. In Modern Geometry, complete quadrangle; figure formed by four points, no three of which are on the same straight line.
Tetrastoon. Courtyard with porticoes on its four sides.
Tetrastyle. Portico with four columns in front.
Tetrathionic Acid. See Dithionic Acid.
Tetrodon. See Plectognathi.
Tetter. Popular name given to several skin eruptions, more especially to various forms of Eczema and Herpes (q.v.).
Tetzcl, Johann, ab.1455-1519. Dominican monk, whose abuse of Indulgences occasioned the breach of Luther with the Roman Church.
Teuflel, Wilhelm Sigismund, 1820-1878. Prof. Tubingen from 1849; historian of Latin literature.
Tcutones. German tribe, living probably near the Baltic. With the Cimbri, they invaded Gaul 113 B.C.
Teutonic. See Germanic.
Teutonic Knights. Military order founded 1190; its members took the three monastic vows. Herman von Salza 1210-39 transferred its sphere of operations from Palestine to heathen Prussia 1230, and founded an empire extending from the Oder to the Gulf of Finland. Its headquarters were removed from Venice to Marienburg 1309. It was the most im1508
portant political power of n. Europe 1350-80. Internal decay and the rising power of Poland weakened it. It was defeated at Tannenberg (e. Prussia) July 15, 1410; gradually lost its territories; was suppressed by Napoleon 1809, and was reorganized 1840 and 1865.
Teutonic mythology. The myths of the Germanic nations, which were transmitted from ancient times, and modified by association with other peoples. They had their gods and goddesses, which presided over the forces of nature, the elements, and the affairs of mankind, and the myths of the dead. See Scandinavian Mythology.
Tcwkiburr. Town of Gloucestershire; scene of Edward IV.'s victory, May 4, 1471, over the Lancastrians. Queen Margaret was made prisoner and her son slain. Its Norman abbey
church, built 1123, measures 317 by 124 ft. across the transepts, with a massive tower 132 ft. high. It was restored by Scott in 1875-79, the later additions being in Early English, Perpendicular and Decorated styles. Pop., 1891, 5,269.
Tcwflk Pasha, Mohammed, 1852-1892. Khedive of Egypt 1879; son of Ismail: succeeded by his son Abbas.
Texas. Largest of the States, on the Gulf of Mexico: area 265,780 sq. m. Stretching over 13 degrees of longitude and 10 of latitude, it contains all variations of surface and of climate. The e. part, along the Gulf coast, is low, marshy, and unheal thful. Further inland, it becomes higher and densely forested. Still further inland is a prairie region, more broken than the prairies of Illinois. This is succeeded by high arid tablelands, reaching their summit in the Llano Estacado, 3,500 to 5,000 ft. high; between, the Pecos and Rio Grande desert plains are intersected by short isolated ranges of mountains. Numerous rivers rise in the Llano Estacado and in the prairie region, and flow s.e. to the Gulf. Along the s.w. border, separating it from Mexico, flows the Rio Grande. Its principal branch is the Pecos, which joins it in the w. deserts. The geology of the State is ;is varied as its surface. The w. two-thirds are underlaid by Cretaceous formations, within which are found areas of Cambrian, Silurian, Carboniferous, and even Quaternary beds. Shoreward from this area of Cretaceous is a broad belt of Eocene, followed by Neocene, while along the Gulf, including all the low-lying country, are Quaternary beds. The industries differ widely in its different parts. In the e. the culture of cotton prevails; further w. that of the cereals as far as comparatively dense settlement has extended. Beyond that, on the w. and s., the ranging of cattle and sheep is the chief industry. In 1890 the value of farms was $399,971,289, of the agricultural product $111,699,430. In recent years the development of the railroad system of T. has gone on with extreme rapidity. In 1893 the mileage of railroads was 9,088. The State has not yet reached the stage of settlement where manufactures become of great importance. 585.000 tons of coal was mined in 1896. Its commerce is largely centered at the port of Galveston, and consists mainly of the shipments of cotton and cattle. Till 1821 the history of T. is that of a Spanish territory. After the purchase of La. by the U. S., Americans began to settle in T., and in 1821, when Mexico became independent of Spain, colonization from the U. S. was permitted and protected by the Mexican
government; but in 1830 the American colonists were placed under military rule, and hence ensued the struggle for independence. The Mexicans were defeated 1836, and till 1845 T. was an independent State. In 1845 it was admitted, against the protest of Mexico, as one of the States. The result was a war, ending in Mexican defeat, the cession of Cal., New Mexico, and the intervening territory, now composing Nevada, Utah, and Arizona, and the payment of $15,000,000. T., on admission to the Union, sold to'the U. S. the portion of its territory between the headwaters of the Rio Grande and Arkansas. The State seceded 1861, and was readmitted with a new constitution 1868. Capital, Austin. Pop., 1890, 2,235.523, over one-fourth colored.
Texa§, University Of. At Austin: opened 1883. It is coeducational, has 30 professors in the College of Arts, with 343 students. The Medical College, at Galveston, opened 1891. has 9 professors, 9 lecturers, and 248 students. The Law School has 144 students under 3 instructors. The Agricultural and Mechanical College, at Bryan, connected 1876, has 23 instructors and 354 students.
Texel. Island of n. Holland, in area ab. 35,000acres; scene of naval battles 1653. 1673, and 1799. Pop. ab. 6,500.
Texier, Charles Felix Marie, 1802-1871. French explorer in Asia. Asia Minor, 4 vols., 1839 and later; Armenia, Persia, and Mesopotamia, 1842-45.
Textile Fabrics and Designing. See Weaving.
Textularidca. Order of perforate Foraminifera. with small hyaline shells or large arenaceous ones, the chambers of which are usually arranged in a spiral or alternately.
Tezcatlipoca. God of the winter sun and of stern law; chief Aztec deity, with his brother Uitzilopochtli, god of the summer sun; worshiped with human sacrifices.
Tezcuco. City of Mexico. 17 m. e. of the capital; held from ab.1120 by a tribe often at war with the dominant race. Its remains are important. Pop. ab. 16.000. Its lake, between it and Mexico, covers ab. 80 sq. m., but is shallow.
Tczcl. See Tetzel, J.
Thacher, George, 1754-1824. M.C. from Mass. (Me.) 17891801; Judge Supreme Court of Mass. and Me. from 1800.
Thacher, James, 1754-1844. Surgeon in Continental army 1776-82, and at Plymouth, Mass. Military Journal, 1823; Medical Biography, 1828; Hist. Plymouth, 1832.
Thacher, Thomas, 1620-1678. Pastor and physician in and near Boston; praised by Cotton Mather.—His son, Peter, 1651-1727, and great-grandson, Peter, D.D., 1752-1802, were noted preachers.—Samuel Cooper. 1785-1818, son of the last, was an early and able defender of Unitarianism.
Thackeray, Anne Isabella. See Ritchie.
Thackeray, William Makepeace, 1811-1863. English humorist and satirist, famous chieflv for the novels Vanity Fair, 1847-18; Pendennis, 1848-50; Esmond, T852; and The
The Paris Sketch-book, 1840; Yellowpluah Papers, 1841; Irish Sketch-book. 1843: Cornliill to Cairo, 1846; Book of Snobs, 1848; Titmarsh, 1848; Humorists of 18th Century, 1852; Four Georges, 1857; and many ballads and lyrics. He was on the staff of Punch from 1842; illustrated several of his books; lectured in America 1855-50; founded the Cornhill Mag. 1859, and edited it till 1862. Though his keen satire was feared and resented, he was kindly, lovable, and eminently human, at heart "rather a sentimentalist than a cynic." For his daughter Anne, see Ritchie, Mrs. Anne I.
Thuddaeiis, or Lebb^eus. One of the twelve Apostles. See Jude.
Thais. Athenian, mistress of Alexander and of Ptolemy, son of Lagus.
Thalamiflorae. Group of polypetalous Dicotyledons, having the stamens inserted on the receptacle. Tiialauiopliora. Foraminifera plus Arcellina. Thalamus. See TORUS. TlialasMCina. See Ch.etifera.
Thalassieolla. Genus of monozoic Radiolaria. It has no skeleton, but has a very complex nucleus. See Peripyl^ea and Tiialassicollida.
Thalassieollida. Family of peripylajan Radiolaria, including forms with a complex intra-capsular nucleus. The skeleton may be wanting or may consist of extra-capsular spicules.
Thalassophora. See Basommatophora.
Thalhcrg, Sigismond, 1812-1871. Swiss-German pianist of high rank, well known in Europe and the U. S.; composer of many pieces for the piano, and of two unsuccessful operas.
Thaler. Silver coin of various German States, standard till 1871; nominal value ab. 72 cents.
Thalcs, ab.640-ab.548 B.C. Of Miletus: one of the Seven Sages; earlier of the Greek philosophers. He held that water or moisture was the principle out of which all things were developed, and is said to have brought to Greece from Egypt the earliest knowledge of mathematics.
Thalia. Muse of comedy.
Thaliacca (thalicea, Conserta). Free-swimming, transparent, barrel-shaped Tunicates. with mantle orifices at opposite ends of the body. The branchiae are band-shaped, and the animal moves by contractions of the branchial cavity. The
Salpa maxima, solitary; S. democratica, chain.
viscera are compressed into a small mass, the nucleus. They are solitary or are united in chains, in double rows usually. There are two orders, Desmomyaria (Salpa;) and Cyclomyaria (Doliolida).
Thallic Sulphate. Tl„(S04),-t-7HaO. Colorless tablets, made by dissolving thallium trioxide in dilute sulphuric acid and evaporating.
Thallium. Tl. At.wt. 204.18, sp. gr. 11.8, sp. ht. .032, mpt. 285° C, valence I. III.; discovered by Crookes in 1861: found in small quantities in a number of iron and copper pyrites anil in a few micas; prepared by boiling the fine dust of sulphuric acid factories with sulphuric acid, and then precipitating with zinc; soft, bluish-white metal. It oxidizes when heated in the air, decomposes water at a red heat, and dissolves in dilute iicids.
Thallium Carbonate. TlaC03. Long prismatic needles, obtained as a precipitate by treatiug the sulphate with barium carbonate.
Thallium Hydroxide. TIOH4-11,0. Long yellow needles, made by precipitating the sulphate with barium hydroxide.
Thallium Iodides. Similar to the chlorides and bromides.
Thallium Monobromide. TIBr. Yellow, crystalline precipitate, obtained by adding a solution of potassium bromide to a thallous salt; soluble with difficulty in water. It fuses at a red heat.
Thallium lUoitoehloride. T1C1. White crystalline substance, turning violet when exposed to light; made bv heating the metal in chlorine.
Thallium Monoxide. T1,0. Black powder, soluble in water; made by heating the hydroxide.
Thallium Nitrate. TINO,. Large, milk-white, rhombic columns, obtained by dissolving the carbonate in nitric acid.
Thallium Sulphide. Tl.s. Black, lustrous, crystalline mass, obtained on fusing the precipitated sulphide.
Thallium Trihromide. TlBr3. Yellow to brown crystalline, hygroscopic substance, soluble in alcohol; made bv treating the monobromide, suspended in water, with bromine.
Thallium Trichloride. TlCls+HaO. Colorless enstals, made by treating the monochloride with chlorine under water.
Thallium Trinitrate. TI(N03),.4H20. Colorless, transparent, deliquescent crystals, made by dissolving the oxide in nitric acid.
Thallium Trioxide. TlsO,. Reddish-brown powder, made by fusing thallium in an atmosphere of oxygen.
Thallium Trlsulphide. TLS,. Black substance, obtained by heating the metal and sulphur together.
Thallogens. See Thallophyta.
Thalloid. Having the characters of a thallus.
Thallophyta. Subkingdom or plants, having the vegetative organs in the form of a Thallus (q.v.), including the Algte or seaweeds, Fungi, and Lichenes or lichens: termed by some Thallogens.
Thallous Sulphate. TI2SO,. Rhombic prisms. Womorphous with potassium sulphate; made by treating the hydroxide with sulphuric acid; soluble in water.
Thallus. Vegetative structure in which there is no distinction between stem and leaves. The typical thallus is a flat, broad structure of one or more layers of cells, as in the devil's-apron, sealettuce, and other sea-weeds; but it may be reduced to a filament of a single row of cells, as in many others.
Thames. Largest and most important river of Gt. Britain, rising in the Cotswold Hills and flowing e.; navigable for large vessels to London. Length ab. 250 m., drainage area 5,102 sq. m.
Thames. River of Ontario, Canada, flowing ab.160 m. s.vv. to Lake St. Clair.
Thames Tunnel. At London; completed 1843;, length 1.300 ft., width 35 ft., height 20 ft.; now used by a railway. Another tunnel Section of Stratified Thallus of RiawJit was completed 1890 for the herbacea: a, cortical stratum: 6.gou
T i „ A aM.ii „i, „„:i dial stratum; c, medullary stratum.
London and couth war K railway; it is 1^ miles long and consists of two tubes, 10 ft. in diameter, one over the other; the cost was $1,500,000. See Subway.
Thamugas. See Timoad.
Thamyris. Legendary bard of Thrace, who challenged the Muses to a trial of skill, and, being overcome, was deprived of sight and the power of song.
Thane (thegn). Anglo-Saxon noble, not by blood, but by service to the king; later, land-owner, knight, or baron.
Thanet, Isle Of. At n.e. end of Kent. Area 26,180 acres: pop , 1891, 57,821. Ramsgate, Margate, and other resorts are on its shores.
Thanet, Octave. See French. Alice.
Thank-Offerings. See Peace-offerings.
Thanksgiving Day. Usually the last Thursday of November; first observed as a harvest festival at Plymouth. Mass., 1621; long peculiar to New England; now universal in the U. S.