Page:Collier's New Encyclopedia v. 10.djvu/290

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VOLOGDA 250 VOLTA 155,498 square miles. Its surface is mostly a vast plain, becoming hilly toward the S., and mountainous toward the E., where the Urals expand into a wild highland tract. Only in the S. of the province is agriculture possible. Most of the province lies in the great forest zone, and 87 per cent, of its sur- face is covered with pine woods. Vo- logda is drained chiefly by the Dwina and its tributaries toward the White Sea; the Petchora flows through the N. E. part to the Arctic Ocean. Hunting and fishing are almost the only employ- ments in the major portion of this prov- ince. Salt, skins, and iron are exported. Pop. about 1,500,000. VOLOGDA, the capital of the province of Vologda, on the Vologda, a tributary of the Suchona; 281^/4 miles N. of Moscow, is an old wide town, largely built of wood, the residence of the governor and a bishop. It has over 50 churches, a theo- logical seminary, a gymnasium, and sev- eral monasteries. Before the World War there were extensive manufactures of sailcloth, leather, soap, matches, linen cloth, glass, white lead and jewelry. Vologda was founded in the 12th century. During the 16th it was a great center of trade with England, and many English settled here. Pop. about 30,000. VOLSCI, a people of ancient Latium, whose language proves them to have been a branch of the Umbro-Sabellian stem, and who, holding the Pontine Marches, the valley of the Liris, and the Volscian Hills, extended from the sea-coast to the Samnite frontier. With Rome they seem from an early period to have waged constant wars, with one of which the legend of Coriolanus is associated, but Rome had entirely sub- dued them by 338 b. c, from which date they vanish as a separate race from history. VOLSK, or VOLJSK, a town of Russia, province of Saratov; on the Volga; 80 miles N. E. of Saratov. It has several churches, a technical school, normal school, etc. There are large quays along the river, and trade in tal- low and skins with Petrograd, in fruit with Nijni Novgorod, and in corn with Astrakhan and Rybinsk was carried on before the World War. A great market is held in autumn. Pop. about 40,000. VOLSUNGS, a famous heroic race in old German legend, its founder Volsung or Walsung, the grandson of Odin, and its brightest ornament Volsung's son. Siegmund. Sigfried or Sigurd, hero of the "Nibelungenlied," is of the same stock. The tale is enshrined in the Old Icelandic Volsungasaga, which has been followed by William Morris in hi3 "Story of Sigurd the Volsung." VOLT (named in honor of Alessandro Volta), in electricity, the unit which ex- presses difference of potential. An elec- trical current is in many respects an- alogous to a flow of water. The funda- mental unit is one of mere quantity, the coulomb, and merely expresses suf- ficient current to do a certain amount of work. But the same quantity of water would flow through a large pipe at one inch per second, and through one- half the diameter at four inches per second. Hence we get the unit of ex- pressing quantity per second (the am- pere) ; and thirdly, as a greater pres- sure or force is required to drive water at a given rate per second through a small pipe, or greater resistance so as to maintain a given quantity per second, in electrical currents we have this force or pressure, considered as the difference of potential or electrical pressure at the two ends of the circuit of wire. The re- sistance of a wire to the passage of a circuit is measured in ohms (units), and a volt is the difference of potential required to drive an effective current of one ampere through a wire interposing the resistance of one ohm. VOLTA, a river of west Africa; which, rising in the Kong Mountains or highlands behind the Ashanti country, runs S. between Ashanti and Dahomey, and reaches the Bight of Benin through the E. part of the British Gold Coast. To left and right of its mouth it forms great lagoons, and on the bar across the mouth a heavy surf runs. VOLTA, COUNT ALESSANDRO, an Italian natural philosopher; born in Como, Italy, Feb. 18, 1745. Two treatises, published in 1769 and 1771, in which he gave a description of a new electrical machine, laid the foundation of his fame. He was successively Pro- fessor of Physics at the gjnnnasium in Como and in the University of Pavia. He invented the electrophorus, electroscope, electrical condenser, electrical pistol, and the voltaic battery in the form known as "crown of cups." He also devised sev- eral other electrical appliances, and in 1800 the voltaic pile. To him is due the theory that electricity is generated by the contact of dissimilar metals, a cor- rection of Galvani's animal electricity theory. In 1782 he made a tour through France, Germany, England, and Holland. In 1801 Napoleon invited him to France, where a medal was struck in his honor. In 1810 he was created a senator of Italy, with the title of count; and in