342 RIO GRANDE DO NORTE RIO NEGRO region ; but their valleys, which are generally from 1 to 4 m. wide, that of the Rio Grande expanding in places to 10 or 15 m., are pro- ductive when irrigated. The principal towns on the Rio Grande are Brownsville, Texas, about 35 m. from its mouth, and Matamoros, Mexico, opposite Brownsville. RIO GRANDE DO NORTE, a maritime province of Brazil, bounded N. and E. by the Atlantic, S. by Parahyba, and W. by Ceani; area about 18,000 sq. m. ; pop. in 1871, about 230,000, of whom about 13,500 were slaves. The coast is bordered by a chain of dangerous reefs and shoals, and the only good port is that of Natal, an irregular bay commonly called Rio Grande. Two watersheds running N. and S. divide the province into three almost equal parts, and give rise to many streams. The only important river is the Piranhas, .which rises in Parahyba, passes through the middle of the province, and empties through five mouths, forming a large delta. It is navigable for 25 m., as far as the town of Assu, on the left bank. The Apody, passing through the western part, is navigable by canoes. Branches of the Borborema moun- tains extend into the province. The surface is sandy near the sea, and arid in the interior, except on the high lands and bordering the rivers, where there are extensive pastures and some forests. Gold, silver, and iron are found in small quantities, amianthus, limestone, crys- tals, and salt exist, and sulphur is met with. Good timber is abundant; gums, resins, bal- sams, Brazil wood, medicinal roots, wild honey, cochineal, and wax are among the natural pro- ductions. The carnahuba palm is extensively cultivated for a great variety of nses. Many tropical fruits abound ; sugar, cotton, mandi- oca, rice, beans, and tobacco are cultivated. The native animals are few, the reptiles nu- merous, many of them venomous. Largo herds of cattle are raised. Sea salt is extensively ex- tracted along the N. coast. The climate is very warm, dry, and unhealthy, severe droughts being frequent in the interior. The province is divided into eight districts. There are 62 public primary schools (41 for boys, 21 for girls), with an average daily attendance of 2,622, five secondary schools, and three pri- vate schools. The foreign exports of the prov- ince in 1873 were: cotton, $385,844; sugar, $165,552; hides, $13,824; timber, $135. The chief towns are Natal, the capital, Imperatriz, Assu, and Macau. RIO GRANDE DO SUL. See Slo PEDRO DO SFL. RIOJA, La. I. A W. province of the Argen- tine Republic, bounded N. and N. E. by Cata- marca, E. by Cordova, S. by San Luis, S. W. by San Juan, and W. by Chili, from which it is separated by the Andes; area, 85,000 sq. m. ; pop. in 1869, 48,498. Besides the Andes, the province is traversed in a generally N. and S. direction by the Jague", Famatina, and Velasco or Rioja ranges, the second containing the Nevado peak, 17,050 ft. above the sea. Be- tween these chains are vast plateaus and val- leys. The only important river is the Ber- mejo, descending from the Andes in the north- west, and draining the valley of Jagft6. Gold, silver, copper, iron, tin, and quartz occur ex- tensively in the Famatina chain, precious stones in that of Velasco, and nickel, lead, antimony, carbonate of soda, salt, nitrate of potash, and nitrate of soda elsewhere. There are now (1875) in operation two gold, seven silver, and two copper mines. Maize, wheat, cotton, olives, grapes, and various other fruits are ex- tensively cultivated; and timber, gums, honey, wax, and cochineal and other dyes are very abundant. Cattle rearing is one of the chief occupations. The manufactures comprise leath- er, cotton and woollen fabrics, laces, rum, cor- dials, and preserved fruits, all of which, with vicufia, guanaco, and puma skins, are largely exported. In 1869 there were 3,000 children attending school. The province is divided into the departments of La Rioja, Arauco, Fama- tina, Vinchina, Guandacol, Independencia, Costa Alta, San Martin, and Belgrano. II. A city, capital of the province, near the E. base of the Rioja mountains, 650 m. N. W. of Buenos Ayres; pop. in 1869, 4,489. It is situated in a vast plain, and has good streets and houses, with a parish church and three churches attached to convents. The surround- ing country is remarkably fertile, and wheat and the vine are extensively cultivated. La Rioja was founded in 1591. KIOM, a city of Auvergne, France, in the de- partment of Puy-de-D6me, near the left bank of the Ambdne, 8 m. N. of Clermont-Ferrand ; pop. in 1872, 10,770. It contains several hand- some public edifices and the ruins of the an- cient ducal palace. It has a college, an insane asylum, and a monument to Desaix, who was born near this town. The chief manufactures are linen, distilled spirits, and articles of wax. There is trade in grain, wine, hemp, leather, preserved fruits, and oil. In the 14th century Riom was the capital of the duchy of Auvergne. RION. See PHASIS. RIO NEGRO. I. A river of South America, an affluent of the Amazon, which rises in the Sierra Tunuhy, an isolated group of hills in the state of Cundinamarca, United States of Colombia. Above the Cassiquiare it is called the Guainia, and a portion of its lower part is known as the Parana Pishuna. After flowing E. about 200 m. from its source, it turns S. to lat. 2 N., where it is joined by the Cassiquiare, whose mouth is 600 yards wide, and which connects it with Orinoco. (See CASSIQUIARE.) About 50 m. below this it enters Brazil, and at the equator is joined by the Uaupes or Ucayari, which rises in the same hills as the Negro, -but pursues a widely divergent course. After the junction the Negro descends over a series of rapids to Sao Gabriel, about 600 m. from its mouth at Manaos, and then becomes navigable, with a current of 3 or 4 m. an hour, flowing E. about 250 m. and receiving many
