TREVES. 453 TRIAL. (London, 1876) ; Woerl, Fiihrer durcli die Stadt Trier (Wurzburg, 1887 J. TREVI, tm've, FouxTAix OF. A noted fouiilain in Rome, with which the superstition is connected that a traveler's return to Rome is as- sured by dropping a coin in its basin and drink- ing its waters. It is built against the facade of the Palazzo Poll and was completed in 1702. The water of the ancient Aqua Virgo spouts from the crevices of the rocks and from the nostrils of the liorsos of Ne]itune, who stands in his chariot above the fountain surrounded by Tritons. TREVIGLIO, tra-ve'lyo. A town in the Province of Bergamo, Italy. 20 miles by rail and by steam tramway east by north of JliUm ( Jlap: Italy, D 2). It has an attractive church. There is a library. The town manufactures silks, woolens, ironware, and chemicals. Population (commune), in 1901, 15,138. TREVISO, tra-ve'zo. The capital of the Province of Treviso, Italy, situated in a fertile valle.y, on the Sile, 18 miles north by west of Venice (Map: Italy, G 2), It is connected with the lagoons of Venice by a canal. The town has a media>val appearance with its high walls flanked with Irastions. The imposing twelfth- century cathedral, restored in the tifteeuth cen- tury, has five cupolas. The Gothic Church of San NiceolO has a curious wooden roof, and is adorned with admira1)Ie frescoes. The Borgo Cavour contains a library of 50.000 volumes and a picture gallery. Among the educational in- stitutions are a technical school, a school of navi- gation, a bisliop's seminary, and an academy of sciences. The city manufactures silk and woolen goods, metal ware, machinery, chemicals, and paper. Population (comnume). in 1881, 31,- 24<1; in 1001, 33.087. Treviso, the Roman Tar- visium, was an important city toward the end of the Roman Empire. It figured among the cities of the Lombard League. It came under the rule of Venice in the fourteenth century. In 1797 it was taken by the Frencli under Mortier, who re- ceived the title of Puke of Treviso. TREVITHICK, Rich.rd (1771-1833). A British mechanical engineer and inventor, dis- tinguished for his im^irovements of the steam engine and as the designer of the first practi- cable locomotive. He was born at Illogan, in Cornwall, and received a common-school educa- tion prcvioiis to becoming an engineer in the mines in his vicinity. Engaged in the construc- tion of pumping and other engines, lie was .asso- ciated with Murdocic, Bull, and other well-known engineers and was constantly experimenting with machinery. He was as well known in his neighborhood for his muscular strength as for his inventive genius. He efTected various im- provements in pumps and designed a high-pres- sure steam engine in 1800 which was soon in wide use in the mines of Cornwall and Wales. Turn- ing his attention to the designing of steam vehicles, as early as 1706 he ftiade a number of models on a small scale, and in 1801 completed a full-size vehicle for which he received a patent in the following year. This steam carriage operated so successfully that Trevithick with the assistance of Andrew Vivian was led in 1804 to build a locomotive engine to operate on the Merthyr-Tydfil tram road. This was the first application of steam to the hauling of loads on a railway and led to the construction of further steam locomotives oi)erating on rails, including one which was exhibited in l^ondon in 1808 on a circular track. As Trevithick understood that the friction of the wheels on the rails was sullieient for the traction of cars on ordinary grades (in distinction from other inventors who employed a cog and rack), and as he was the first to use a return fine boiler and a steam jet in the ehimnej', and to couple together the wheels of a locomotive, he is considered by many entitled to the credit of being the real inventor of the locomotive steam engine. It is, however, to Stephenson (q.v.) that we must look for the perfection of a practical application of the machine. See Locomotive, in which article will be found descriptions of Trev- ithick's locomotives. See also R.ilways. After devoting himself to the construction of steam drills and dredging machines he became in- terested in an unsuccessful attempt to tunnel the Thames, and also carried on experiments on en- gines suitable for ship propulsion and other pur- poses. In 1816 Trevithick went to Peru, where a number of his engines had been introduced into the silver mines, and after being successful in several undertakings, lost his entire property through the outbreak of war, which forced him to retire from the country. At Cartagena in 1827 he encountered Robert Stephenson (q.v.) , who as- sisted him to return to England. The remainder of his life was spent in further experiments, few of which came to a successful outcome, and he died in poverty. While Trevithick reaped but little material reward for any of his inventions, yet he made many discoveries which were of the greatest use to other engineers when practically applied and successfully developed. His work for the steam engine stands out conspicuous and ranks him among the most prominent engineers and inventors of the nineteenth century. Con- sult: Trevithick, Life of Richard Trevithicl; (London, 1872) ; Smiles, Lives of Engineers (ib., 1861). TRIAB (from Lat. irias, from Gk. rpids, number three, triad, from rpeis, treis, three). In music, a chord of three tones built upon any tone with its third and fifth above. According to the character of the intervals the character of the triad varies materially. Thus. C E G con- sists of a major third + a minor third; C Efe G of a minor third + a major third; C E G8 of two major thirds; C Eb Gb of two minor thirds. These triads are known as major, minor, aug- mented, and diminished triads, respectively. If in four or five part writing one or two tones of a triad are doubled, the character of the triad is not at all affected. See Harmony. TRIAL (OF. trial, from trier, to try, choose, thresh, from INIL. tritare, to thresh, rub, frequentative of Lat. terere, to rub, thresh ; con- nected with OChurch Slav, trieti, irSti, Lith. iriti, trinti, to rub). A regular and formal examination or inquiry into the material facts of a controversy in issue before a competent tribunal, in order finally to determine the re- spective riglits of the parties thereto. Trials may be divided into two classes : those by a judge and jury, and those before a judge without a jury. In a legal action the trial is usually before a jury. (For the ordinary steps in a jury trial, see Juby.) In courts of equity, trials are
