a river in Bolivia and Brazil, the largest right tributary of the Amazon. The Madeira River is formed by the confluence of the Mamore and Beni rivers, rising in the Andes. The river is 3,230 km long from the upper reaches of the Mamore and drains an area of 1,158,000 sq km. The upper reaches of the river skirt the Brazilian Highlands forming a number of rapids and falls; from Porto Velho it flows through the Amazon lowland. In its lower reaches a right branch flows into the Amazon, and together with the Amazon and the Madeira, forms Tupinambaranas Island, with an area of about 14,500 sq km. High water usually occurs in summer (October to May), the rainy season. The discharge in the lower reaches is 4,200 cu m per sec at low water and 39,000 cu m per sec at high water. The water level may fluctuate 12 m or more. The river is navigable as far as Porto Velho, 1,060 km upstream. Porto Velho, Humaita, and Manicore are the principal cities along the river.
a strong grape wine with an alcohol content of 18-20 percent by volume and a sugar content of 4 to 9 percent, having a distinctive flavor and bouquet. The wine is aged in barrels in artificially heated rooms or in glass rooms heated by the sun. Ordinary Madeiras are stored at 60°-65°C for three months, medium-quality Madeiras are kept at 50°-55°C for four to six months, and high-quality Madeiras are stored at 40°-50°C for not less than six months. The best Madeiras are aged for another two years. After it has been treated by heat, the wine is blended. The wine derives its name from the island of Madeira in the Atlantic Ocean, where it was first produced. In the USSR the best Madeira is produced in the Armenian SSR and on the Southern Crimean Shore.