Arizona, a territory of the United States, situated between lat. 31° and 37° N. and lon. 109°and 114° 40' W., bounded N. by Utah, E. by New Mexico, S. by Mexico, and \V. by California and Nevada; area estimated at 113,000 sq. m. No complete survey of the territory has been made. It is divided into five counties: Maricopa, Mohave, Pima, Yavapai, and Yuma. Tucson, in Pima county (pop. 3,224), is the capital and largest town in the territory. Arizona City, in Yuma county (pop. 1,144), is a prosperous business place, situated at the junction of the Gila and Colorado rivers. Prescott. the former capital (pop. 668), is situated in central Arizona, and is the headquarters of the military department of Arizona. In 1870 the population of the territory, exclusive of Indians, was 9,658, of whom 3,849 were native and 5,809 foreign born; 1,240 were born in the territory. The total number of Indians was 32,083; of these 4,352 were on reservations and at agencies, and 27,700 were nomadic. Many of these Indians are friendly to the whites, but the greater number are intensely hostile. Of the friendly Indians, the Pimas and the Maricopas rank first in numbers and civilization. They occupy a reservation on the Gila river, about 200 m.

E. of Arizona City. The Papagos live S. of the Gila, along the line of Sonora. The Mohaves and the Yumas live along the Colorado, the Utes on the upper Colorado, and the Moquis and Navajos in N. E. Arizona. These tribes are engaged in agriculture and stock-raising. Of the hostile Indians the Apaches are the most powerful and warlike. They comprise several tribes distributed over the greater portion of middle and eastern Arizona; their raids extend all over the terri-tory, with the exception of a narrow strip along the Colorado river and a portion of the lower Gila. Besides the Apaches, the Hualpais or "Wallapis, living in the Cerbat range near the Diamond river, and in part of the Aquarius range, are the only dangerous Indians. - The middle and N. E. portions of the territory consist of elevated plateaus from 3,000 to 8,0C0 ft. above the sea level, with occasional bluffs and volcanic cones rising from 500 to 2,500 ft. above the plateau. The numerous parallel ranges of mountains have a general N. W. and S. E. course, and form long valleys in the same direction.

The most marked exceptions to this general direction are the Mogollon range in the east, which extends nearly E. and W. and joins the Sierra Blanca, and an E. and W. range stretching beyond Arizona into New Mexico. The axis of the Black mountains and the Cerbat range, in the N. W. part of the territory, lies very nearly N. and S. The S. portion of the territory is a plain with a slight elevation above the sea, amounting at the mouth of the Gila to only 200 ft. From this plain isolated mountains and mountain ranges rise abruptly. In central Arizona the Sierra Prieta and the Aztec range send foot hills out in every direction, and their flanks sink very gradually to the level of the high plateau surrounding the San Francisco mountain toward the N. E., and to the mesas or table lands sloping toward the Colorado on the S. W. The elevation of the town of Prescott is over 6,000 ft. above the sea, while the Tonto and San Francisco plateaus, E. and N. E. of Prescott, roach an altitude of from 8,000 to 9,000 ft. The San Francisco, a grand volcanic cone, is the highest mountain in Arizona, its summit being over 11,000 ft. above the sea.

X. and 1ST. E. of the San Francisco mountains, an immense mesa, increasing in altitude toward the Utah line, extends for hundreds of miles. - The largest river of the territory is the Colorado, which is formed by the junction of the Green and Grand rivers in the S. part of Utah, and has a southerly course along the W. boundary of Arizona. It has a very rapid current, and is navigable as far as Callville, 612 m. above its mouth. The canons formed by the passage of the river through the lofty table lands are unequalled in grandeur. In the Grand cation of the Colorado the deep and narrow current flows between massive walls that rise to a perpendicular height of nearly 7,000 ft. above the water. The principal tributaries of the Colorado are the Colorado Chiquito, which flows N. W. through the N. part of the territory, the Diamond river, and Bill Williams's Fork, into which flows the Santa Maria. The Gila rises in New Mexico, flows W. through the S. part of Arizona, and joins the Colorado about 180 m. above the gulf of California. It is a very narrow stream with a swift current, shallow during most of the year, but in the rainy season vastly increasing its volume.

Its principal tributaries in Arizona are the Salado or Salt river, Verde, San Carlos, Bonito, and Prieto from the north, and Santa Cruz and San Pedro from the south. - Granite, red and white sandstone, limestone, slate, quartz, and metamorphic rocks abound in the mountains. The plains along the lower Gila are entirely made up of quaternary and tertiary deposits, which also form the great Sonora desert S. of that stream. In the Colorado valley, the sedimentary strata consist of quaternary and tertiary gravels and conglomerates, varied in a few localities by a layer of white infusorial earth. The bottom lands consist of calcareous sands and clays, the former predominating. The mountain chains are composed of granites, syenites, porphyries, trachytes, greenstone, basalt, and metamorphic slates. A section of the Grand canon of the Colorado, 6,800 ft. above the sea level and 5,500 ft. above the river, exhibits the following sedimentary strata down to the underlying granite: upper carboniferous limestone; cross-stratified sandstone; red calcareous sandstone, with gypsum; lower carboniferous limestone; limestones, shales, and grits - Devonian; limestones, mud, rocks, and sandstones - Silurian; Potsdam sandstone; granite.

No one of the mineral-bearing territories of the Pacific slope is richer than Arizona, though the mines have not been generally worked. The inaccessibility of the territory (it being off from the great overland lines of travel and without seaports), and the fierceness of the Apaches, have prevented the full development of its mineral wealth. The mountains of southern and central Arizona are nearly all mineral-bearing, and contain lodes of gold, silver, copper, and lead. The ores of silver found in this region are argentiferous galena, native silver, auriferous sulphuret of silver, black sul-phuret of silver, sulphate of silver, sulphate of iron, combined. The ores of copper are usually the sulphnrets, principally gray. Nearly all the silver and copper lodes show traces of gold; and placers have been found at many points, but have not proved sufficiently extensive to attract much attention. Gold is found in central Arizona, the ore yielding from $25 to $100 per ton. Iron in carbonates and oxides is abundant, and traces of tin and nickel exist. Platinum (metallic) is shown in the placers of the Black canon. Copper, silver, and quicksilver are found together in a rare combination, but the lode is not large.