ROCKLAND, a t. in Maine, on the w. side of Penobscot bay, 40 m. s.e. of Augusta. It has a broad and deep harbor, and 80 lime-kilns, making 1,200,000 casks of lime yearly, chiefly shipped to Boston and New York. Its commerce employs 18 ships, 40 barks and brigs, and 150 schooners. It has 3 banks, 2 newspapers, 8 churches, etc. Pop. '60, 7,316; in '70, 7,074.

ROCKLAND (ante), co. seat of Knox co., Me., on the Knox and Lincoln railroad, 40 m. s.e. of Augusta. Shipbuilding is extensively carried on. Among the manufactures are boots and shoes, carriages, harnesses, machinery, and tools. A government building for a custom-house and post-office was erected in 1874-75. Water is brought 24 m. by a costly system of water-works. There is a court-house and a public library. The city was set off from Thomaston in 1848 as East Thomaston, took its present name in 1850, and became a city in 1854. Pop. '80, 7,599.

ROCKLAND, Mass. See page 900.

ROCKLAND LAKE, a beautiful sheet of water in Rockland co., N. Y., 30 m. n. of New York city, 1 m. from the Hudson, and 160 ft. above its surface. It is celebrated for furnishing 200,000 tons of pure ice, annually harvested by about 1000 men, for the supply of New York, and for export.

ROCKLING, Motella, a genus of fishes of the cod and haddock family (gadida), having an elongated body, compressed toward the tail; the first dorsal fin very slightly elevated, and very delicate; the second dorsal and the anal fins long, continued almost to the tail fin. Several species are found on the British coasts, and are distinguished among other things by the number of their barbules, three, four, or five. The largest of them is never more than 19 or 20 in. long; the smallest, the MACKEREL MIDGE (M. glauca), only about an inch and a quarter. None of the species is much regarded by fishermen, one reason being that decomposition takes place very rapidly after they are taken out of the water, although, when quite fresh, they are not bad for the table.

ROCK-OIL. See NAPHTHA.

ROCKPORT, a t. in Essex co., Mass., on the Gloucester branch of the Eastern railroad; pop. '80, 3,912. It has churches, schools, a newspaper, banks, hotels, and a public library. There are granite quarries. The chief occupations are fishing and farming. Pigeon Cove, a summer resort, is in Rockport, which is at the extremity of Cape Ann.

ROCK RIVER rises in the south-eastern portion of Wisconsin, and runs s. w. into Illinois, thence s. w., and empties itself into the Mississippi 3 m. below Rock island. Its course of 200 m. is through one of the most beautiful and fertile regions in the world, known as the "Rock River Country." Its frequent falls give abundant water-power, and it is crossed by 12 lines of railway.

ROCK-ROSE. See CISTUS.

ROCK-SALT is common salt (chloride of sodium) occurring as a mineral and in a solid form. It is always mixed with various impurities. It is found massive or crystallized, its crystals generally cubes, its masses very often either granular or fibrous. It is white, gray, or, owing to the presence of impurities, more rarely red, violet, blue, or striped. For its chemical and other qualities, see SALT. It is a very extensively-diffused mineral, and in some places forms great rock and even mountain masses. A hill of rock-salt near Montserrat, in Spain, is 500 ft. high. The island of Ormuz, in the Persian gulf, is formed of rock-salt. The Indus, in the upper part of its course, forces its way through hills of rock-salt, rising in cliffs 100 ft. above the river. In many parts of the world rock-salt is found in beds under the soil or other rocks. Those of Cheshire in England are particularly celebrated, as at present yielding almost all the salt used in Britain, great part of which is pumped from them in the form of brine. Part is also obtained by mining, as at Northwich. The mines of Wieliczka in Poland are of great extent. The workings are at depths varying from 200 to 740 ft., and the salt at the deepest working is the purest. Some of the chambers in the mines are said to be 300 ft. high. Blasting by gunpowder is often necessary in the mining operations. The mines give employment to 1200 or 1400 workmen; and they have been wrought for centuries. Vast quantities of rock-salt occur in many parts of Asia, Africa, and America. In Caramania and Arabia, rock-salt is sometimes used for building houses, the dryness of the climate rendering its solubility unimportant.—The salt which crystallizes on the margins and bottoms of salt lakes may be regarded as a variety of rock-salt. Concerning the salt of the ocean, the salt found in many desert regions as an effervescence on the ground or on rocks, the salt with which sandstone and other rocks are impregnated, etc., see SALT.

ROCK-SOAP, a mineral consisting of silica, alumina, peroxide of iron, and water, the silica nearly one-half, the alumina and the water sometimes nearly each one-fourth of the whole. It is earthy, easily broken, black or nearly so, very soft, and easily cut with a knife, is greasy to the touch, and adheres strongly to the tongue. It is valued by painters for crayons. It is found in a number of places on the continent of Europe, and occurs in trap rocks in the isle of Skye. It is only found massive.

ROCKVILLE, a village in Vernon, Tolland co., Conn., on a branch of the New York and New England, and a branch of the Connecticut Central railroads; pop. 1880, 5,902. It has churches, schools, hotels, a newspaper, gas and water works. There are several woolen-mills and other factories, for which the water power is furnished by Hockanum river.

Rocky.

ROCKWALL, a co. in n.e. Texas, drained by branches of the Sabine and Trinity rivers; about 200 sq.m.; pop. '80, 2,984-2,952 of American birth. The surface is mostly rolling prairie. The soil is fertile. The principal productions are wheat and corn. Co. seat, Rockwall.

ROCK-WORK, an ornamental structure often introduced into gardens, for the culti vation of plants such as grow on or amongst rocks. It is made of rough blocks of stone rudely piled together, with earth, etc. Simple as it seems, it is very difficult of construction; and too often, after much expense, it has a paltry and ridiculous appearance. ROCKY MOUNTAINS, that portion of the great ranges of mountains in the central and western portions of North America which lies in the United States and British possessions, a continuation of the Cordilleras of Mexico, between the Pacific ocean and 105° w. long., and reaching from Mexico to the Arctic ocean. In the United States the Rocky mountains extend over a breadth of 1000 m., and cover an area of 980,000 sq. miles. From lat. 32° tɔ 40° n., the ranges bear nearly n. and s.; between lat. 40° and 45° n., their course is n.w.; then, after a more northerly bend, they keep a course nearly parallel to that of the Pacific, with many detached ranges and peaks, one of which, mount Elias, lat. 61° n., long. 141° w., is 17,800 ft. high, and marks the boundary-line of longitude between Alaska and the British possessions. Mount Shasta, in the coast-range in North California, is 14,000 ft. high; Fremont's peak, near the western boundary of Wyoming, and the sources of the Yellowstone and Colorado rivers, is 13,570 feet. In British Columbia, mount Brown, lat. 53°, is 16,000 ft.; and mount Hooker, 15.700 feet. The passes have elevations of 6,000 to 7,000 ft., and a vast territory is from 4,000 to 5,000 ft. above the level of the sea. The central range of the Rocky mountains forms the ridge which divides the rivers that fall into the Pacific from those that fall into the Arctic ocean, Hudson's bay, and the gulf of Mexico, and whose head-waters are often interlocked; but between the eastern and western ranges lie the territory of Utah and the state of Nevada, in which are large rivers having no other outlets than lakes, generally salt, as Great Salt lake in Utah, and Humboldt's lake, the outlet of Humboldt's river, in Nevada. The tops of the higher ranges are covered with perpetual snow, and their lower regions abound with artemesias, odoriferous plants, and sunflowers. The rocks are metamorphic gneiss, granites, porphyries, mica and talcose slates, and gold-bearing quartz, with deposits of mercury, silver, carboniferous limestone, coal, and petroleum. Anthracite has been found near the gold-mines of Santa Fé, and copper in New Mexico.

ROCKY MOUNTAINS (ante). Explorations and surveys of the vast extent of elevated plateaus, and the many separate ranges of this mountain system, have been made by the U. S. government with exceeding thoroughness. Colorado, Wyoming, New Mexico, and Utah, with the portion of the range which traverses them, have nearly complete scientific surveys, including their topographical and geologic features. The parts of the range traversing Idaho, Montana, Wyoming, Oregon, and Washington are less advanced in their surveys, which are still in progress. The first comprehensive exploration of this central part of the continent was made by capts. Lewis and Clarke in 1803-6 under the direction of president Jefferson, in connection with their exploration of the upper Missouri and the Columbia rivers. Maj. Z. M. Pike in 1805-7 trav ersed the plains to Pike's peak (named after him), discovered the head-waters of the Arkansas in the heart of the range in Colorado, and crossed into the great basin on the w. side of the range. In 1819-23 col. S. H. Long was sent with a party to make a scientific survey of the same region; the peak n. w. of Denver was named in his honor. The real first explorers of all the great interior parts of the continent were the hunters and trappers employed by the British and American fur companies, the latter operating from St. Louis. The most extensive explorations by any one scientific party, however, were made in the three expeditions led by col. John C. Fremont under government authority. The first in the winter of 1842-43 made a survey of the South pass and discovered the Wind River mountains, the highest peak of which Fremont ascended and measured, and it received his name. The second expedition started in May, 1843, and explored the route by Bridger's pass over the mountains, located the Great Basin of Salt lake, and crossed to the Columbia river, returning by the way of the Great Basin. In 1846 gen. P. Kearney traversed the Rocky mountains with a military party to California, and returned overland in 1847. Fremont's last explorations were in 1848 up the Rio Grande from Santa Fé and thence across the great chain w. to the Great Basin. In 1853 the government ordered extensive surveys in the Rocky mountain country, the results of which are contained in 13 vols. of maps and reports. These were the bases of the support given by the government to the construction of the Union Pacific railway 1866-70. The U. S. scientific surveys completed and in progress, under the direction of prof. Hayden, I. W. Powell, Clarence King, and other able scientists, will be almost unequaled in their completeness. The search for the precious metals also fills the region with an advance corps of unscientific explorers.

The vastness of area of the Rocky mountains, their erratic and widely separated ranges, spurs, and groups of mountains, and the extent of the great plateaus at high elevations, impress the mind far more than their picturesqueness or scenic character. The Andes in South America form a much loftier and narrower chain. Persons familiar with them, or with the Alps, find the scenery of the Rocky mountains relatively tame. Travelers by the Union Pacific railway which gains the first continental divide

1

Rocky.

at Bridger's "pass," at an altitude of 7,000 ft., are astonished to see a broad rolling gravelly plain stretching away on all sides, and the mountains forming the horizon apparently of no great height. Rising from a base of plains 4,000 to 6,000 ft. above the sea, the mountains only begin at those levels.

The Rocky mountains are the summit divide of North America, and a continuation of the chain of the Andes of South America. At the isthmus of Darien, sinking to a minimum elevation of 100 ft. above the sea, they increase in height northward through Central America, where their well-watered summits, on the Pacific side in Costa Rica, have the most delightful of climates. In Guatemala they rise into the volcanic elevations of Fuego and Agua, 13,000 and 14,000 ft. high respectively; and thence into Mexico, where, in lat. 19, the chain is 300 m. wide and rises into the loftiest elevations of the continent, in a chain of mountains running e. and w., forming the volcanoes of Popocatepetl, 17,540 ft.; Orizaba, 17,176 ft.; Toluca, 16,610 ft.; and Iztaccihuatl, 15,705 feet. North of this loftiest part, between the eastern and the western declivities of the great mountain mass, is the plateau of Mexico, a comparatively level plain from 3,000 to 6,000 ft. above the sea (averaging 5,000 ft.) extending from the city of Mexico 1200 m. northerly to the United States line, of a width varying from 200 to 500 miles. See MEXICO. The highest part, or main chain, where it enters the United States from western Chihuahua, is known as the Sierra Madre, and is there 180 m. in breadth, of purely mountain country, the highest parts of which are about 8,000 ft. above the sea. The eastern slopes are well-watered and fertile. Cotton and the grape are grown on the lower parts. The Sierra Madre mountains spread into a number of branching ranges in Arizona, difficult to classify; nowhere rising into mountains of so great height as in southern Mexico or Colorado, and forming elevated plateaus of a more irregular character than those of Mexico. The easterly side of the chain where it enters New Mexico has an altitude of from 6,000 to 8,000 ft., increasing northwardly to the Colorado line, near the source of the Rio Grande, where many peaks rise to 14,000 feet: Through Colorado the range maintains a grand elevation. Here the U. S. surveys have been most elaborate, and the attention given to the country by the discoveries of great numbers of mines, and ready access afforded by railways, have made this state the most noted for the study of the mountains. See COLORADO. The streams which flow e. to the Mississippi and s.w. to the gulf of California rise in snow-covered ranges inclosing a system of "parks" which have given the name of "the park system" to this part of the Rocky mountains. It is bounded n. by the Laramie plain, e. by the great plains, w. by the cañon-rifted plateaus of the Colorado, and on the s. merges into the valley of the upper Rio Grande. North park is the basin of the head streams of the North fork of the Platte; Middle park is the basin of the sources of Blue river (the North fork of Grand river) flowing to the Colorado; South park is the basin of the springs of the South Platte, and one of the head streams of the Arkansas; and San Luis park the basin at the source of the Rio Grande. All these parks lie at elevations from 5,000 to 7,000 ft. above the sea, and gather the drainage of the snowy ranges to carry them to the gulf of Mexico on the e. and the gulf of California on the west. For geologic and topographical surveys of this region see COLORADO and NEW MEXICO. The easterly range in view from Denver is called the Colorado range; its continuation n. forms the Medicine Bow range; w. of the Middle and North parks is the Park range. The Colorado range by a westward trend connects at mount Lincoln with the Park range, and divides North park from Middle park. The Park range, which lies nearest to the great plateaus of the head-waters of the Colorado w. of Middle park, becomes a middle range further 8., and lies e. of the upper valley of the Arkansas. A third range, having its n. head in the mountain of the Holy Cross, becomes the westerly range. Its n. parts take the name Sawatch range, and the southern the San Juan range. It has more elevations reaching to 14,000 ft. than any other part of the Rocky mountains in the United States. South of the Sawatch range the country is broken into great mountain masses too isolated to suggest a range. The Pike's peak group is the most north-easterly group of this character. The following table gives the altitudes of the main elevations of these ranges:

Roderic.

North of Colorado and on the line of the Union Pacific railway there is a relatively low part of the great chain, which was formerly known by the names of its lowest points, as South pass, Bridger's pass, etc. The Union Pacific railway took the latter. The Black hills are the most easterly outlying spur of the range n. of these passes. The main chain trends n.w., and spreads over an area 300 m. wide in Wyoming; its easterly ranges in the w. part of that territory taking the names Big Horn mountains and Wind River mountains. The greatest elevation and some of the most picturesque parts of the range are at the Three Tetons, near the w. line of Wyoming, s. of the National park at the head of the Yellowstone. See NATIONAL PARK OF THE YELLOWSTONE. On the n. side of the Snake river, in Idaho, the range develops a volcanic character up to recent times. Isolated and exceedingly irregular and lofty uplifts fill the whole of cen tral Idaho, and nearly all of Montana. See IDAHO; MONTANA. South of the great valley through which the Union Pacific railway is laid there are the lofty and isolated ranges named Wahsatch and Uinta. The former is the most abrupt elevation on the eastern border of the great basin. Its western slopes drain into the Jordan river and Great Salt lake, and its eastern slopes into the Colorado. Its greatest elevations, Twin peaks, Lone peak, and mount Nebo, are about 12,000 ft. above the sea, and as their summits are not more than 20 m. from the valley of the Jordan, 4,500 ft. above the sea, they form a peculiar group which arrests and attracts the moisture from the air currents of those regions and concentrates upon their heads an amount of snow-fall in the winter greater than upon any other part of the Rocky mountains in the United States. Near the sources of the streams that empty into the Jordan the avalanches and snow-slides are more frequent and dangerous than elsewhere. The Uinta mountains is a range or mountain mass connecting the Wahsatch with the main ranges east.

North of the United States the range is supposed to have an equal breadth of ramification, and its elevations are greater. Mounts Hooker and Brown, 300 m. n.w. of Idaho, have an altitude of 15,700 and 16,000 ft. respectively. The range is thence northward continuously lofty, and forms the westerly wall of Mackenzie's river, flowing into the Arctic sea, but is pierced in several places by streams rising w. of the range, and emptying either into that river or into streams that flow into Hudson's bay.

Some authors name all the mountains between the basin of the Mississippi and the Pacific as portions of the Rocky mountains, and classify them into park ranges, basin ranges, plateaus, Sierras of Nevada, Coast range, and Cascade mountains. The three latter ranges have no more reason to be included with the Rocky mountains than the Alleghanies. The uplift beginning in the Pacific ocean, and forming the peninsula of Lower California, continues northward into the lofty Sierras of Nevada, the Cascade mountains in Oregon and Washington, and through Alaska to mount St. Elias, 16,758 ft. high, near the shore of the n. Pacific. In the Sierras of California, mounts Shasta, Tyndall, and many others are upward of 14.000 ft. high; and mounts Jefferson and Hood in Oregon, and mounts Rainier and Baker in Washington, are upwards of 12,000 ft. This great range is distinctly separated from the Rocky mountain system by the valley of the Colorado river, the great interior basins, and the valleys of the upper Columbia, Fraser, and Yukon rivers. For the geology, natural history, topographical, and climatic details of the Rocky mountain system, see the states and territories traversed by them. For Pacific coast ranges see CALIFORNIA, OREGON, WASHINGTON, and ALASKA..

ROCO CO, a name given to the very debased style of architecture and decoration which succeeded the first revival of Italian architecture. It is ornamental design run mad, without principle or taste. This style prevailed in Germany and Belgium during last century, and in France during the time of Henry IV.

ROCROI, a small t. of France, in the dep. of Ardennes, 15 m. n.w. of Mézières, is a fortress of the fourth class, and is situated in a fine, extensive plain, bounded on al! sides by the forest of Ardennes. Pop. '81, 1649. It is memorable for the victory gained by the great Condé (then duke of Enghien) over the Spaniards, May 19, 1643. The Spanish army was composed of veteran bands of Walloons, Spaniards, and Italians; and their general, Don Francisco de Mellos, the governor of the Low Countries, was a commander worthy of his army. The French (22.000) were also good troops; but their general, Condé, was a young and inexperienced officer. At first the battle was unfavor able to the French, but at last the Spaniards were thrown into irretrievable rout. The count of Fuentes, the commander of the redoubtable infantry, and 10,000 of his men, were among the slain; and 5,000 men, with all the cannon, many standards, and the baton of the count de Mellos, were captured. But, far beyond all material losses, the renown of invincibility, first acquired by the Spanish infantry on the field of Pavia (1525), and confirmed at St. Quentin, Gravelines, and Prague, was destroyed.

ROD, called also a pole, or linear perch, a measure of length of 54 yards, or 164 feet. The square rod, called generally a rood, is employed in estimating masonry, and contains 16 161, or 2724 square feet.

RODEN TIA (Lat. gnawers), or RODENTS, in the system of Cuvier, an order of mammalia, almost exactly corresponding with the glires of Linnæus. The order is a truly natural one, and is therefore universally recognized by naturalists. The rodentia are small quadrupeds; the largest of them—the capybara-not being equal in size to a hog.