Arizo´na, a former territory of the United States, admitted into the union as a sovereign State on 14th Feb., 1912, is bounded south by Mexico, west by California and Nevada (the River Colorado forming the greater part of the boundary), north by Utah, and east by New Mexico; area, 113,956 sq. miles. The surface is generally mountainous, but many fertile and well-watered valleys lie between the ridges. Part of the surface consists of deserts often entirely destitute of vegetation. The territory belongs to the basin of the Colorado, which passes through a portion of it, besides forming the boundary; while the Gila and Little Colorado, tributaries of the Colorado, traverse it from east to west. The canyons of the Colorado form a wonderful feature, the river flowing for hundreds of miles in a deep rocky channel with walls rising perpendicularly to the height of 1500 to 6000 feet. In some parts timber is plentiful. The rainfall is small, and irrigation has been employed for agricultural purposes. Large tracts of elevated land have been found excellently adapted as pastures for sheep and cattle. The territory is rich in copper, gold, silver, lead, and other minerals, and mining is largely carried on, with much copper smelting and refining. The capital is Phœnix. Pop. 29,053. The Southern and the Santa Fé Pacific Railways traverse it. Pop. (1920), 333,903 (of which 171,468 are white), exclusive of Apaches and other Indians on reservations (area, 29,017 sq. miles; pop. (1920), 42,400).
Arjish Dagh, the loftiest peak of the peninsula of Asia Minor, at the western extremity of the Anti-Taurus Range, 13,150 feet; an extinct volcano; on the N. and N.E. slopes are extensive glaciers.
Ark, the name applied in our translation of the Bible to the boat or floating house in which Noah resided during the flood or deluge; to the floating vessel of bulrushes in which the infant Moses was laid; and to the chest in which the tables of the law were preserved—the ark of the covenant. This last was made of shittim-wood, overlaid within and without with gold, about 3¾ feet long by 2¼ feet high and broad, and over it were placed the golden covering or mercy-seat and the two cherubim. It was placed in the sanctuary of the temple of Solomon; before his time it was kept in the tabernacle, and was moved about as circumstances dictated. At the captivity it appears to have been either lost or destroyed.
Arkansas (ar´kan-sa¨ or ar-kan´sas), one of the United States of America, bounded north by Missouri; east by the Mississippi, which separates it from the States of Mississippi and Tennessee; south by Louisiana and Texas; and west by the Indian Territory and Texas; area, 53,335 sq. miles. The surface in the east is low, flat, and swampy, densely wooded, and subject to frequent inundations from the numerous streams which water it. Towards the centre it becomes more diversified, presenting many undulating slopes and hills of moderate elevation. In the west it
rises still higher, being traversed by a range of hills called the Ozark, which attains a height of 2000 feet, some peaks rising to 3000. In various parts the prairies are of great extent; the forests also are extensive, principally of oak, hickory, ash, cotton, linden, maple, locust, and pine. Coal and other minerals are worked. The principal rivers, all tributaries of the Mississippi, are the Arkansas, the Red River, the St. Francis, and the Washita. Near the centre of the State are warm springs, much resorted to for chronic rheumatic and paralytic affections. The climate is subject to great extremes of heat and cold, and in the lower districts is unhealthy to new settlers. The staple products are cotton and maize; fruit is tolerably abundant. Many districts are admirably adapted for grazing, and great numbers of excellent cattle are reared. Arkansas was colonized as early as 1685 by the French. As part of Louisiana it was purchased by the United States in 1803. It was made into a separate territory in 1819, and admitted into the Union in 1836. It was one of the seceding States. The capital is Little Rock. The enumerated population in 1920 was 1,750,995.
Arkansas, a river of the United States, which gives its name to the above State, the largest affluent of the Mississippi after the Missouri. It rises in the Rocky Mountains, about lat. 39° N., long. 107° W., flows in a general south-easterly direction through Colorado, Kansas, the Indian Territory, and lastly through the State of Arkansas, and after a course of 2170 miles enters the Mississippi. During greater part of the year it is navigable for steamboats for 800 miles.
Arkite. See Explosives.
Ark´low, a town in Ireland, County Wicklow, on the right bank of the Avoca, which falls into the sea about 500 yards below the town; the scene of a severe fight during the rebellion of 1798. Fishing is the chief industry. Pop. 5042.
Ark´wright, Sir Richard, famous for his inventions in cotton-spinning, was born at Preston, in Lancashire, in 1732, died 1792. The youngest of thirteen children, he was bred to the trade of a barber. When about thirty-five years of age he gave himself up exclusively to the subject of inventions for spinning cotton. The thread spun by Hargreaves' jenny could not be used except as weft, being destitute of the firmness or hardness required in the longitudinal threads or warp. But Arkwright supplied this deficiency by the invention of the spinning-frame, which spins a vast number of threads of any degree of fineness and hardness, leaving the operator merely to feed the machine with cotton and to join the threads when they happen to break. His invention introduced the system of spinning by rollers, the carding, or roving as it is technically termed (that is, the soft, loose strip of cotton), passing through one pair of rollers, and being received by a second pair, which is made to revolve with (as the case may be) three, four, or five times the velocity of the first pair. By this contrivance the roving is drawn out into a thread of the desired degree of tenuity and hardness. His inventions being brought into a pretty advanced state, Arkwright removed to Nottingham in 1768 in order to avoid the attacks of the same lawless rabble that had driven Hargreaves out of Lancashire. Here his operations were at first greatly fettered by a want of capital; but two gentlemen of means having entered into partnership with him, the necessary funds were obtained, and Arkwright erected his first mill, which was driven by horses, at Nottingham, and took out a patent for spinning by rollers in 1769. As the mode of working the machinery by horse-power was found too expensive, he built a second factory on a much larger scale at Cromford, in Derbyshire, in 1771, the machinery of which was turned by a water-wheel. Having made several additional discoveries and improvements in the processes of carding, roving, and spinning, he took out a fresh patent for the whole in 1775, and thus completed a series of the most ingenious and complicated machinery. Notwithstanding a series of law-suits in defence of his patent rights, and the destruction of his property by mobs, he amassed a large fortune. He was knighted by George III in 1786.