and is subject to continual gradual stretching, necessitating frequent readjustment. In all respects, except speed, the tricar is inferior to the small car. (A. Sp.)
TRIDENT (Lat. tridens, tri-, tres, three and dens, tooth), a
three-toothed or three-pronged fork or spear. It is and has
been from primitive times the typical instrument for spearing
fish, the Scottish “leister” (Norw. ljoster), and was thus taken
as the badge or emblem of the Greek Poseidon, the god of the
sea. In Homer (cf. Il. xii. 27; Od. lv. 506 seq.) Poseidon is
armed with the τρίαινα (another word is τριόδους, cf. Pind.
Ol. ix. 45). The trident as the symbol of the sovereignty of
the sea is found as early as Archilochus (c. 700 B.C.); a more
familiar example is to be found in Aristophanes (Eq. 839).
The emblematically figure of Britannia holds the trident as
mistress of the sea. In the gladiatorial shows of ancient Rome
the retiarius was armed with a trident as a weapon.
TRIDYMITE, a mineral consisting of silicon oxide or silica, SiO2, but differing from quartz in crystalline form. The crystals are small, thin hexagonal plates or scales, which are usually twinned together in groups of three; hence the name of the mineral, from Greek τρίδυμος, triplet. The apparent hexagonal plates are themselves pseudo-symmetric twins of optically biaxial material, and the exact crystalline form is doubtful. The plates are colourless and transparent and have a vitreous lustre. The hardness is 7 and the specific gravity 2.3 (that of quartz being 2.65). Unlike quartz, it is soluble in a boiling solution of sodium carbonate. Tridymite occurs in the cavities of acid volcanic rocks (rhyolite, trachyte and andesite); the best-known localities are Cerro San Cristobal near Pachuca in Mexico, the Euganean Hills near Padua, and the Siebengebirge on the Rhine. Probably identical with tridymite is the form of silica known as asmanite, found in the meteorite which fell at Breitenbach in the Erzgebirge, Bohemia. (L. J. S.)
TRIER (French Trèves), an ancient city of Germany, formerly
the capital of an archbishopric and electorate of the empire,
and now the seat of a Roman Catholic bishop and the chief
town of a governmental department in the Prussian province
of the Rhine. Pop. (1885) 33,019, (1905) 46,709 (86% Roman
Catholics). It is situated on the right bank of the Moselle,
about 6 m. from the frontier of Luxemburg and 69 m. S.W. of
Coblenz, on the main lines of railway from Coblenz to Metz and
from Cologne to Saarbrücken. The city lies in a fertile valley
shut in by vine-clad hills, and the picturesque red sandstone
buildings of the old town are interspersed with orchards and
gardens. On the north, east and south boulevards with gardens
follow the line of the medieval walls, which have mostly
disappeared. The Roman city extended much farther south
and east.
Trier contains more important Roman remains than any other place in northern Europe. Perhaps the oldest remains are some of the piers and buttresses of the bridge over the Moselle, which may date from about 28 B.C. The well-preserved amphitheatre just outside the modern town to the south-east was probably built in the reign of Trajan or Hadrian. Its eastern side is built into the hill, its longer diameter is 76 yds., and it accommodated seven or eight thousand spectators. In 306 the emperor Constantine the Great caused multitudes of Frankish prisoners to be thrown to the beasts here, and in 313 made a similar spectacle of the captive Bructeri. The most remarkable Roman building in Trier is the Porta Nigra, the north gate of the city, a huge fortified gateway, 115 ft. long, 75 to 93 ft. high and 29 ft. deep, built of sandstone blocks blackened with age (whence the name), and held together with iron clamps. The age of this building is very uncertain; it has been assigned to dates ranging from the 1st to the 4th century A.D. It is also called the Simeonstor, after a Greek hermit who inhabited it. On his death in 1035 Archbishop Poppo converted the gate into two churches, one above the other, but all the additions except the apse have now been removed. In the south-east corner of the city are the picturesque ruins of the Roman imperial palace, and near the bridge are the extensive substructures of the 4thcentury Roman baths, 660 ft. in length. On the Constantinsplatz stands the magnificent brick basilica, probably of the age of Constantine, though the south and east walls are modern. Having been converted into a palace for the Frankish kings and their deputies, it passed in 1197 to the archbishops, and was restored (1846–1856) and turned into a Protestant church. The adjoining barracks were formerly the elector's palace. Another Roman basilica forms the nucleus of the cathedral. Built under the emperors Valentinian I. and Gratian as a quadrilateral hall with four huge granite columns (now removed) in the centre, it was converted into a church about the close of the 4th century, and restored by Bishop Nicetius about 550. It is the most important pre-Carolingian church in Germany. Archbishop Poppo and his successors in the 11th and 12th centuries extended the cathedral westwards and added an apse at each end. The vaulting of the nave and aisles and the beautiful cloisters were added in the 13th century. In the vaults are buried twenty-six archbishops and electors. Among the monuments are those of the electors Richard von Greiffenklau (d. 1531) and Johann von Metzenhausen (d. 1540), fine examples of German Renaissance work. The most famous of the relics preserved in the cathedral is the “Holy Coat of Trier,” believed by the devout to be the seamless robe of the Saviour, and said to have been discovered and presented to the city by the empress Helena. Since 1512 it has been periodically exhibited. The exhibition of 1844, which was attended by more than a million pilgrims, aroused protests, resulting in the formation of the sect of German Catholics (q.v.). In 1891 nearly two million pilgrims viewed the coat, and eleven miraculous cures were claimed.
The cloisters connect the cathedral with the church of Our Lady (Liebfrauenkirche), a beautiful building in the form of a circle intersected by a cross, with a lofty vault, built 1127–1143, and said to be the oldest Gothic church in Germany.
The earliest churches were without the walls. Of these St Matthias in the south, now represented by a 12th-century building, has a Christian cemetery of the Roman age.
In the market-place is the market cross, said to date from 958, and a beautiful Renaissance fountain, the Petersbrunnen, erected in 1595. Close by are the Steipe or Rotes Haus, formerly the town hall, of the 15th century, and the Frankenturm or propugnaculum, of the 10th century, said to be the oldest stone domestic building in Germany.
The Provincial Museum (1885–1889) contains many Roman and medieval antiquities. The town library contains about 100,000 volumes, including some valuable examples of early printing. Among its most treasured MSS. are the codex aureus, a copy of the gospels presented to the abbey of St Maximin by Ada, a reputed sister of Charlemagne, and the codex Egberti of the 10th century.
At Igel near Trier is a very remarkable Roman column, 83 ft. high, adorned with sculptures. It dates from the 2nd century, and was the family monument of the Secundini. At Nennig is a fine Roman mosaic pavement.
The industries of Trier include iron-founding, dyeing and the manufacture of machinery. There is a school of viticulture and a very considerable trade in Moselle wines, especially during the annual auctions.
History.—Trier had had two periods of greatness, firstly as the favourite residence of Constantine the Great and his successors in the west, and secondly as the capital of a powerful spiritual electorate.
The Treveri or Treviri, from whom the city derived its name, were one of the most powerful tribes among the Belgae, and according to Julius Caesar, who conquered them in 56 B.C., possessed the best cavalry in Gaul. Attempts have been made to show that they were of German origin (see Belgae), but although they were doubtless subject to Germanic influences, they spoke a Celtic language. Their chiefs, Indutiomarus, who raised a rebellion against the Romans in 54 B.C., and his successor Cingetorix have Celtic names, and St Jerome, who had lived in Trier, declares that their language in his day (c. 370) resembled that of the Galatians. An insurrection under Julius
