Page:The New International Encyclopædia 1st ed. v. 19.djvu/112

* TEETH. 36 TEGEA. enamel, and cement — and a central pulp cavity. The human tooth fits into the jaw-bone much like a peg into its socket. This manner of union is termed 'fjoniphosis.' The tooth does not, how- ever, occupy the entire socket, for there is be- sides a lining of periostevun, which at the root turns upward around the tooth as far as the neck, where it becomes continuous with the gums. This packing around the tooth is some- what elastic and allows of slight motion. The elasticity of the packing doubtless diminishes the shock which would be caused in mastication were the teeth rigidly attached in their bony sockets. When the periosteum is inflamed the swelling pushes the tooth outward in the socket and loosens it. The dentine forms the great mass of the tooth, surrounds the pulp cavity, and is covered, in the liunian tooth by a layer of enamel, the hardest of animal tissues; in other mammals this layer of enamel may cover all or only a part of the Exposed portion of the tooth, or "may be absent. The condition that more commonly prevails is that the enamel envelops the entire crown of the tooth and stops rather abruptly at about the level of the gum. In its finer structure dentine is in some cases difficult to distinguish from true bone. Typical dentine, such as exists in human teeth, differs from bone both in structure and in chemical composition, and is known as 'hard' or 'unvascu- lar' dentjne. It is hard, elastic substance with a yellowish white hue, which is made up of a number of minute, wavy, branching tubules, parallel to one another and opening internally into the pulp cavity. These tubuli contain finely cylindrical prolongations (dentinal fibres) from cells in the pulp cavity, intimately connected with the nerves of the pulp. The different kinds of dentine have been classified as (1) hard or unvascular dentine; (2) plici-dentine ; (3) vaso-dentine ; (4) osteo-dentine. The unvascu- lar dentine has been described above. In the second class the pulp cavity is irregular in out- line, with many tubes and canals traversing the dentine in various directions, some carrying blood- vessels. Such a condition obtains in many of the lower vertebrates and in some mammals. The osteo-dentine closely approaches bone in struc- ture. In it pulp and calcified tissue are mixed up, for there is no distinct pulp cavity. Such dentine is found in the teeth of many sharks. The cement forms a coating over the roots of the teeth and when unusually thick may even unite the roots of contiguous teeth. In the hu- man teeth it extends upward to cover the edge of the enamel. It covers, at first, the entire teeth of certain vertebrates, such as the elephant, and covers the crowns of the teeth of ruminants. It is derived from the tooth-follicle and is closely allied to bone. The cavity of the tooth is filled with the tooth- pulp, which is composed of a gelatinous matrix and contains cells, nerves, and blood-vessels. The outermost cells, known as 'odontoblasts,' form a layer next the hone. These cells are con- nected b}' processes with one another and with deeper lying cells, and on the periphery the pro- cesses extend into the dental tubuli. The gums are continuous with the mucous membrane of the mouth, but are much thickened. Within the gums are tendinous faciculi. and others extend up into them from the periosteum. These give the gums hardness. They are richly supplied with blood-vessels, but have few nerves. The gums are continuous with the periosteum of the alveoli, a connective tissue richly supplied with blood-vessels and nerves. Bibliography. Tomes, Manual of Dental An- atomy, Human and Comparative (London, 1876) ; Owen, Odontography (London, 1840-45). See Integument; Skeleton; Dentistky. TEFFT, Benjamin Franklin (1813-85). A Methodist Episcopal clergyman. He was born near Utica, N. Y., and graduated at Wes- leyan L'niversity, lliddletown. Conn., 1835. He taught in the Maine Wesleyan Seminar}', Kents Hill. Me., 1835-1839; was principal of Providence Conference Seminary, East Greenwich, R. I., 1841; professor of Greek and Hebrew languages and literature in Indiana Asbury L'niversity (now De Pauw University), Greeneastle, Ind., 1843-1846; editor of The Ladies' Repository, Cin- cinnati, O., 1846-50; president of Genesee Col- lege, Lima, N. Y., 1851-1854; chaplain of First Maine Cavalry, 1861; United States consul at Stockholm and acting Minister to Sweden, 1862; Commissioner of Immigration from the North of Europe for the State of Maine, 1864; and edi- tor of The Northern Border, Bangor, Me., 1873- 78. He wrote: The Shoulder Knot (1850); Hungary and Kossuth (1851) ; JVehster and His Masterpieces (1854); Methodism Successful (1860); The Present Crisis (1861). TE'GEA (Lat., from Gk. Te7^j. An ancient city of Southeastern Arcadia, Greece. Its ter- ritory included the southern part of the great eastern plain of Arcadia, of which the northern part was occupied by Mantinea (q.v. ). It was a place of considerable size, and it appears to have included the modern villages of Hagios Sos- tis. Pala'O-Episkopi, Piali, and Ibrahim Effendi, south of Tripolitza, though but few remains are visible, partly because of a deep deposit of al- luvium, and "partly from the destruction due to the later inhabitants. The most important ruins are those of the great temple of Athena Alea, built by Scopas (q.v.), and now (1904) in pro- cess of excavation by the French School at Athens. The dimensions of the temple ( about 163 X 70 feet) and important fragments of its sculp- tures were determined by Milchhofer in 1879. The city was celebrated in the heroic legends, and for a long time seems to have opposed Sparta on equal "terms, but during the sixth century B.C. was forced to join the Spartan league. At Ther- mopyloe. we are told, were five hundred Tegeans, and at Phita-a three thousand, of whom one-half were hoplites. Later they were again involved in war with Sparta, and after two defeats re- mained true allies until the invasion of Epami- nondas (B.C. 370), when a democratic govern- ment replaced the aristocracy, and the city joined in the foundation of Megalopolis. Later we find Tegea in the .Etolian League, in alliance with Sparta, forced into the Achaean League, at war with Sparta, and sharing in the confused politics which mark the history of the lesser Peloponne- sian cities during the third and second centuries. A good account of the place was given by Pau- sanias in the second century of our era, and it seems to have been one of the most flourishing towns of Arcadia till it was sacked by Alarie. Consult, besides the larger works on the Pelo- ponnesus (q.v.) by Dodwell, Leake, Curtius, and