TECTJMSEH. 84 Indian lands. In the summer of 1808 Teeumsph and liis brother established a village near the mouth of Ti]ipeeano(' t'reek in Indiana, and here Tecuiiiseh put into practice some of his ideas for returning to the. virtuous primitive condition of the Indians Ijy prohiliiting the use of whisky and other demoralizing practices introduced by the whites. Two years later he went on a visit to the southern Indians, especially the Choctaw, Creek, Cherokee, and Seminole, and by his wonderful eloquence is considered to have kindled among them the flame that in 1813 burst into the Creek War. In his absence, however, his fol- lowers were defeated on November 7, 1811, by a force under General William Henry Harrison. (See Tippecanoe, Battle of.) In the follow- ing year he joined the British at Maiden, and early in August routed a force of Oliio militia, but was defeated and wounded in the skirmish of Maguaga. Despite his defeat, hoAvever, he wa3 commissioned a brigadier-general in the British Army, and with several hundred Indians assisted in the capture of Detroit. In January, 1813, he played an important part in the siege of Fort Meigs (q.v. ), and prevented the massacre of prisoners taken in the sortie from the fort. After Perry's victory on Lake Erie Tecumseh protested against the British retreat from ISIalden. He accompanied the retreating army, however, and at the battle of the Thames (q.v.) was killed while bravely resisting the attack of the mounted Americans under Colonel Eiehard M. Johnson. Tecumseh was a man of many high qualities, with impressive manners and wonderful natural eloquence. The part he played in the War of 181*2 was an exceedingly important one. Indeed, as a Canadian historian has pointed out, it is quite conceivable that had it not been for Te- cumseh, the Americans would have conquered Canada. Consult: Drake, Life of Tecumseh and His Brother, the Prophet, with an Historical Sketch of the Shawnee Indians (Cincinnati, 1841 ) ; and Eggleston, Tecumseh and the Shaw- nee Prophet (New York, 1878). TEDAS, ta'daz. The northern division of the Tibbus (q.v.), living in Tibesti and the adjoin- ing oases of the Eastern Sahara, and connected with the outside world by the main camel route between the city of Tripoli and Lake Chad. In this portion of the Great Desert are inex- haustible supplies of rock salt, and the Tedas em- ploy thousands of camels in conveying this mate- rial throughout Central Africa. TED'DINGTON. A town in IMiddlesex, Eng- land, on the Thames, 21,4 miles southwest of Richmond (Map: London and vicinity, F 4). The municipality maintains reading rooms and recreation grounds, and provides garden allot- ments. The National Physical Laboratory was inaugurated here in 1902. Population, in 1891, 10,0.52; in 1901, 14,029. TE DEUM. A well-known h^nnn, so called froiu its opening w-ords (Te Denm laiidamus, te dominum confitemur. We praise Thee, O God, we acknowledge Thee to be the Lord), commonly sung on all occasions of triumph and thanks- giving, and a theme upon which the most celebrated composers have exercised their mu- sical genius. The h^Tnn is one of the most simple, and at the same time the most sol- emn and majestic and most admired in the TEETH. whole range of hymnology. Its authorship is uncertain. Picturesquely and uncritically it has been described as the joint production of Saints Ambrose and Augustine, into which they both burst forth by a common inspiration on occasion of the baptism of Augustine. From this supposed origin, the Te Deum is eommonlj' called the Am- brosian hymn. It is ascribed by other author- ities to Hilary of Poitiers, but is most prob- ably considerably later. Besides its general us« on occasions of jojous celebrations, the Te Deum forms part of the daily matins of the Roman breviary, and is recited at the end of matins on all festivals, and on all Sundays except those of Advent and Lent. With a similar exception, it forms part of the morning prayer of the Anglican Praj'er Book, being sung after the first lesson. Its use dates from the sixth century. TEES. A river of Northern England. It rises on Cross Fell, Cumberland, and flows east be- tween the counties of Durham and York. It enters the North Sea 10 miles below Stockton, to which town it is navigable for small vessels. Length, 80 miles (Map: England E 2). TEETH (AS. <a.}),Goth. tuni us, OHG. zand, zan, Ger. Zahn, tooth ; connected with Olr. dct, Bret., Welsh daiit, Lith. dantis, Lat. dens, Gk. dSolj!, odous, dSuiv, odOn, Skt. danta, tooth, probably originally the pres. part., with loss of the initial vowel, of Skt. ad. Gk. e5ei.v,edein,'Lat.edere,toent, OChurch Slav, yamt, Lith. edmi, edi, I eat, Olr. ith, Goth, itan, OHG. e~::an, Ger. essen, AS. etan, Eng. eat). Calcareous organs imbedded in the skin within or near the mouth in most verte- brates, acting primarily for the prehension and trituration of food. Some teeth, such as the tusks of the wild boar or of the elephant, have secondarily acquired another function, namely, that of offensive and defensive organs, especially with reference to combats between rival males. Teeth are dermal structures, homologous with the placoid scales or denticles which cover the entire body of fishes (q.v.). At the anterior end. say of the body of a dogfish, the skin turns in to form the lining or mucous membrane of the mouth and with it the scales are carried. In fishes these dermal denticles appear in the skin very early both in their ontogenetic and phylo- genetic history, but do not occur in Amphioxus or in c.yclostomcs. They first appear in selachians in the form of small denticles or spines arranged in longitudinal and transverse rows, each at- tached to a basal plate, and directed caudad. Both ectoderm and mesoderm take part in the formation of these dermal denticles, as in the case of the teeth of the higher vertebrates. The name 'tooth-germ' is given to the tissue that is destined to develop into the teeth. The meso- derm forms a papilla which secretes dentine in its outermost layer. Within the dentine there is a cavity filled with mesodermal tissue and blood vessels. From this cavity fine tubules pass into the dentine. Outside the dentine is a layer of enamel secreted by ectodermal cells. The first impulse toward tooth-formation seems to reside in the derma. As the dermal papilla grows it comes to be covered by a layer of large columnar cells from the epidermis. The enamel is secreted from the lower surface of these epidermal cells. As the dermal cells multipl_y. they give rise to an elongated papilla which projects backward. The deep-lying connective-tissue layers of the
