URBINO 136 •UREA car, to a car dragged along by a cable, a car driven by electricity derived from an elevated trolley or from underground contact, all of these being supplemented by the motor omnibus. The systems of urban transportation in most American cities were at first established by local capitalists, but later companies usually combined to control the lighting, electric railway and gas facilities, while in other cities the municipal authorities have taken the transportation systems into their hands. The elevated lines in New York were formerly operated with small steam locomotives, but later displaced steam with electricity. In recent years the systems in the larger American cities have become very complicated. Accord- ing to recent figures, for example, Boston had 231 miles of surface street railway, of which 197 miles had a second track. There were about 14 miles of rapid-tran- sit track, v/ith a second track. In a re- cent fiscal year the gross earnings amounted to $17,269,000 and the operat- ing expenses amounted to $11,288,000. The number of passengers carried to- taled 346,317,000. The miles run were 57,806,000, These results included the traffic on elevated lines and subways. In New York almost every form of transportation facilities known is in vogue. There are elevated roads, oper- ated by current from a third rail; with electric surface lines below them, oper- ated by underground contact; four track subways lower still; lower still another subway, and still lower, at 42d St., the Queensboro Tube which runs from Man- hattan under the East River to Long Island. The tremendous north and south traflUc in New York has made it neces- sary to develop the city transportation to the highest limit, and as a result Man- hattan Island is a great object lesson in such transportation. The subway sys- tem is the most extensive in the United States, and it has been the model on which the systems of other cities, both in the European countries and the United States, have been constructed. See Street Railways. TJRBINO, an ancient town of central Italy; in the province of Pesaro and Ur- bino; between the Foglia and Metauro rivers, remote from the highways of commerce. It is a town of narrow, tor- tuous streets, with an archbishop's cathe- dral and other churches; a magnificent ducal palace (1447; restored, and now housing the fine art institution) ; a free university, dating from 1564, but now attracting less than 100 students, and the house in which Raphael was born, now the town museum Cheese, silk, pins. and some majolica ware are manufac- tured, but not the majolica for which the place was famous for a century and a half after 1475. Urbino, anciently the Ur- binum Hortense of Umbria, was a muni- cipium under the Romans and was the seat of a line of independent dukes from 1474 to 1G26. On the death then of the last duke Urban VIII. took possession of the duchy as a vacant fief; and it be- longed to the Papal states till 1860, when it became part of the kingdom of Italy. Pop. about 20,000. URDEE, or URDY, in heraldry, pointed. A cross-urdee is one in which the extremities are drawn to a sharp point instead of being cut straight. TTRE, ANDREW, a Scottish chemist; born in Glasgow, Scotland, May 17, 1778. After lecturing with some success on chemistry, natural philosophy, and ma- teria medica, at Glasgow, he was nom- inated to the post of astronomer, on an observatory being established in that city. In 1821 he produced a valuable work, entitled a "Dictionary of Chem- istry." He took up his residence in the metropolis in 1830, and was four years afterward appointed chemist to the Board of Customs. In 1837 he produced his "Dictionary of Arts, Manufactures, and Mines," a work of immense labor and research, which has gone through many editions, and also has been translated into the leading continental languages. He died in London, Jan. 2, 1857. UREA, one of the few organic bases of animal origin. It forms an essential constituent of the urine of all animals, and is most abundant in that of the mammalia, particularly so in the case of the carnivora. It is the principal out- let of nitrogen from the system, after the materials which compose the animal tissues have experienced oxidation under the influence of inspired air, A person in good health secretes about an ounce of urea daily. Dumas made several fruitless attempts to form urea from the azotized constituents of the body, but Bechamp has recently succeeded in doing so, by subjecting albumen to the oxidizing ac- tion of permanganate of potash. Urea does not appear to be formed in the kid- neys, these organs appearing to act more as filters in separating it from the mass of blood in which it is formed before it reaches them; perhaps it is produced in the liver. Urea may be formed artificially in several ways, and was one of the first organic products made from inorganic materials. The easiest method of pro- curing it is by heating together 56 parts of ferrocyanide of potassium with 28
