were “the primitive types from which all the organisms of the higher classes had arisen by gradual development,” and he laid down as a fundamental proposition “that all living forms are the results of physical influences which are still in operation, and vary only in degree and direction.” Like many after him, he directed attention to the influence of the male elements in fertilization as a source of variation, but laid emphasis only on the intra-organismal power of adaptation to surroundings. Whatever opinion be entertained in regard to the priority and the importance of the contribution made by Treviranus to the theory of evolution, it is at least certain that he was a learned naturalist and an acute thinker. His most important later work of a synthetic nature was entitled Erscheinungen und Gesetze des organischen Lebens (1831).
His younger brother, Ludolph Christian Treviranus (1779–1864), studied medicine at Jena, and was successively professor of medicine at Bremen lyceum (1807), professor of natural history at Rostock (1812), professor of botany and director of the botanical garden at Breslau (1816), and professor of botany at Bonn (1830).
TREVISO (anc. Tarvisium), a town and episcopal see of
Venetia, Italy, capital of the province of Treviso, 49 ft. above
sea-level. Pop. (1901), 16,933 (town); 36,433 (commune).
It is situated on the plain between the Gulf of Venice and the
Alps, 18 m. by rail N. of Venice, at the confluence of the
Sile with the Botteniga. The former flows partly round its
walls, the latter through the town; and it has canal communication
with the lagoons. It is an old town, with narrow
irregular colonnaded streets and some interesting old frescoed
houses. The cathedral of San Pietro, dating from 1141 and
restored and enlarged in the 15th century by Pietro Lombardo,
with a classical façade of 1836, has five domes. It contains a fine
“Annunciation” by Titian (1519), an important “Adoration
of the Shepherds” by Paris Bordone (born at Treviso in
1500), and frescoes by Pordenone. There are also sculptures
by Lorenzo and Battista Bregno and others. The Gothic
church of San Niccolo (1310–1352) contains a fine tomb by
Tullio Lombardo, and a large altarpiece by Fra Marco Pensabene
and others; in the church and adjoining chapter-house are
frescoes by Tommaso da Modena (1352), some frescoes by whom
(life of S. Ursula) are also in the Museo Civico. The Monte
de Pietà contains an “Entombment” by an artist of the school
of Pordenone (wrongly attributed to Giorgione). The churches
of S. Leonardo, S. Andrea, S. Maria Maggiore, and S. Maria
Maddalena also contain art treasures. The Piazza dei Signori
contains picturesque brick battlemented palaces—the Salone
del Gran Consiglio (1184) and the Palazzo del Commune
(1268). Treviso is the seat of various manufactures—ironworks
and pottery, macaroni, cotton-spinning and rice-husking,
paper, printing, brushes, brickyards, flour mills—and is the
centre of a fertile district.
The ancient Tarvisium was a municipium. It lay off the main roads, and is hardly mentioned by ancient writers, though Pliny speaks of the Silis as flowing “ex montibus Tarvisanis.” In the 6th century it appears as an important place and was the seat of a Lombard duke. Charlemagne made it the capital of a marquisate. It joined the Lombard league, and was independent after the peace of Constance (1183) until in 1339 it came under the Venetian sway. From 1318 it was for a short time the seat of a university. In the 15th century its walls and ramparts (still extant) were renewed under the direction of Fra Giocondo, two of the gates being built by the Lombardi. Treviso was taken in 1797 by the French under Mortier (duke of Treviso). In March 1848 the Austrian garrison was driven from the town by the revolutionary party, but in the following June the town was bombarded and compelled to capitulate.
TREVITHICK, RICHARD (1771–1833), English engineer
and inventor, was born on the 13th of April in the parish of
Illogan, Cornwall, and was the only son of Richard Trevithick
(1735–1797), manager of the Dolcoath and other important
Cornish mines. He attended his first and only school at Camborne,
and was in general a slow and obstinate scholar, though
he showed considerable aptitude for figures. He inherited
more than the average strength for which his family was
famous; he stood 6 ft. 2 in. in height, and his feats in wrestling
and throwing weights were unexampled in
the district. At the age of eighteen he began to assist his
manifesting great fertility of mechanical invention,
father, and, was soon recognized as the great rival of James Watt in
improvements on the steam-engine (q.v.). His earliest invention
of importance was his improved plunger pole pump
(1797) for deep mining, and in 1798 he applied the principle
of the plunger pole pump to the construction of a water-pressure
engine, which he subsequently improved in various ways.
Two years later he built a high-pressure non-condensing steam engine,
which became a successful rival of the low-pressure
steam-vacuum engine of Watt. He was a precursor of George
Stephenson in the construction of locomotive engines. On
Christmas Eve 1801 his common road locomotive carried the
first load of passengers ever conveyed by steam, and on the
24th of March 1802 he and Andrew Vivian applied for a patent
for steam-engines in propelling carriages. In 1803 another
steam vehicle made by him was run in the streets of London,
from Leather Lane along Oxford Street to Paddington, the
return journey being made by Islington. He next directed
his attention to the construction of a steam locomotive for
tramways, with such success that in February 1804 at Pen-y-darran
in Wales he worked a tramroad locomotive which was
able to haul twenty tons of iron; a similar engine was supplied
to the Wylam Colliery (Newcastle) in the following year. In
1808 he constructed a circular railway in London near Euston
Square, on which the public were carried at the rate of twelve
or fifteen miles an hour round curves of 50 or 100 ft. radius.
Trevithick applied his high-pressure engine with great success to
rock boring and breaking, as well as to dredging. In 1806 he
entered into an engagement with the board of Trinity House,
London, to lift ballast from the bottom of the Thames, at
the rate of 500,000 tons a year, for a payment of 6d. a ton.
A little later he was appointed to execute a driftway under the
Thames, but the work was abandoned owing to the water
breaking in. He then set up workshops at Limehouse, for
the construction of iron tanks and buoys. He was the first
to recognize the importance of iron in the construction of
large ships, and in various ways his ideas also influenced the
construction of steamboats. In the application of steam to
agriculture his name occupies one of the chief places. A high-pressure
steam threshing engine was erected by him in 1812
at Trewithen, while in the same year, in a letter to the Board
of Agriculture, he stated his belief that every part of agriculture
might be performed by steam, and that such a use of
the steam-engine would “double the population of the kingdom
and make our markets the cheapest in the world.” In
1814 he entered on an agreement for the construction of engines
for mines in Peru, and to superintend their working removed
to Peru in 1816. Thence he went in 1822 to Costa Rica. He
returned to England in 1827, and in 1828 petitioned parliament
for a reward for his inventions, but without success. He died,
penniless, at Dartford on the 22nd of April 1835.
A Life of Richard Trevithick, with an account of his Inventions was published in 1872 by his third son, Francis Trevithick (1812–1877).
TREVOR, SIR JOHN (1626–1672), English politician, was a son of Sir John Trevor (d. 1673) of Trevelyn, Denbighshire. His father was a member of parliament under James I. and Charles I., and sat also in the parliaments of Oliver and of Richard Cromwell, and was a member of the council of state during the Commonwealth. One of his uncles was Sir Sackvill Trevor (d. c. 1640), a naval officer, who was knighted in 1604; and another was Sir Thomas Trevor (1586–1656), the judge who decided in favour of the Crown in the famous case about the legality of ship-money, and was afterwards impeached and fined. Sir John Trevor was returned to parliament in 1646 as member for Flintshire. After filling several public positions under the Commonwealth and Protectorate he was a member of the council of state appointed in February 1660 and under Charles II. he rose to a high position. Having purchased the office of secretary of state he was knighted and entered upon its duties
