extending from the Rio Grande inland for 300 to 350 m. is quite destitute of vegetation where irrigation is not used. There is little rainfall in this region and the climate is hot and dry. The more elevated plateaus and valleys have the heavier rainfall, but the average for the state is barely 39 in.; an impermeable clay substratum prevents its absorption by the soil, and the bare surface carries it off in torrents. The great Bolsón de Mapimí depression, in the S.E. part of the state, was once considered to be an unreclaimable desert, but experiments with irrigation have shown its soil to be highly fertile, and the conversion of the narrow valleys of the sierras on the west into irrigation reservoirs promises to reclaim a considerable part of its area. The only river of consequence is the Conchos, which flows north and north-east into the Rio Grande across the whole length of the state. In the north there are several small streams flowing northward into lakes. Agriculture has made little progress in Chihuahua, and the scarcity of water will always be a serious obstacle to its development outside the districts where irrigation is practicable. The climate and soil are favourable to the production of wheat, Indian corn, beans, indigo, cotton and grapes, from which wine and brandy are made. The principal grape-producing district is in the vicinity of Ciudad Juárez. Stock-raising is an important industry in the mountainous districts of the west, where there is excellent pasturage for the greater part of the year. The principal industry of the state, however, is mining—its mineral resources including gold, silver, copper, mercury, lead and coal. The silver mines of Chihuahua are among the richest in Mexico, and include the famous mining districts of Batopilas, Chihuahuilla, Cosihuiriachic, Jesús María, Parral, and Santa Eulalia or Chihuahua el Viejo. There are more than one hundred of these mines, and the total annual yield at the end of the 19th century was estimated at $4,500,000. The state is traversed from north to south by the Mexican Central railway, and there are short branches to some of the mining districts.
Chihuahua originally formed part of the province of Nueva Viscaya, with Durango as the capital. In 1777 the northern provinces, known as the Provincias Internas, were separated from the viceroyalty, and in 1786 the provinces were reorganized as intendencias, but Chihuahua was not separated from Durango until 1823. An effort was made to overthrow Spanish authority in 1810, but its leader Hidalgo and two of his lieutenants were captured and executed, after which the province remained passive until the end of the struggle. The people of the state have been active partizans in most of the revolutionary outbreaks in Mexico, and in the war of 1862–66 Chihuahua was loyal to Juárez. The principal towns are the capital Chihuahua, El Parral, 120 m. S.S.E. of the state capital, in a rich mining district (pop. 14,748 in 1900), Ciudad Juárez and Jimenez, 120 m. S.E. of Chihuahua (pop. 5881 in 1900).
CHIHUAHUA, a city of Mexico, capital of the above state, on the Chihuahua river, about 1000 m. N.W. of Mexico City and 225 m. S. by E. of El Paso. Pop. (1895) 18,279; (1900) 30,405. The city stands in a beautiful valley opening northward and hemmed in on all other sides by spurs of the Sierra Madre. It is 4635 ft. above sea-level, and its climate is mild and healthy. The city is laid out regularly, with broad streets, and a handsome plaza with a monument to Hidalgo and his companions of the revolution of 1810, who were executed here. The most noteworthy of its public buildings is the fine old parish church of San Francisco, begun in 1717 and completed in 1789, one of the best specimens of 18th-century architecture in Mexico. It was built, it is said, with the proceeds of a small tax on the output of the Santa Eulalia mine. Other prominent buildings are the government palace, the Porfirio Diaz hospital, the old Jesuit College (now occupied by a modern institution of the same character), the mint, and an aqueduct built in the 18th century. Chihuahua is a station on the Mexican Central railway, and has tramways and telephones. Mining is the principal occupation of the surrounding district, the famous Santa Eulalia or Chihuahua el Viejo mines being about 12 m. from the city. Next in importance is agriculture, especially fruit-growing. Manufacturing is making good progress, especially the weaving of cotton fabrics by modern methods. The manufacture of cotton and woollen goods are old industries in Chihuahua, but the introduction of American skill and capital toward the end of the 19th century placed them on an entirely new footing. The manufacture of gunpowder for mining operations is another old industry.
Chihuahua was founded between 1703 and 1705 as a mining town, and was made a villa in 1715 with the title San Felipe el Real de Chihuahua. Because of the rich mines in its vicinity it soon became one of the most prosperous towns in northern Mexico, although the state was constantly raided by hostile Indians. In 1763 it had a population of nearly 5000. The war of independence was followed by a period of decline, owing to political disorder and revolution, which lasted until the presidency of General Porfirio Diaz. In the war between Mexico and the United States, Chihuahua was captured on the 1st of March 1847, by Colonel A. W. Doniphan, and again on the 7th of March by General Price. In 1864 President Juárez made the city his provisional capital for a short time.
CHILAS, a hill village in the North-West Frontier Province of India. It is dominated by a fort on the left bank of the Indus, about 50 m. below Bunji, 4100 ft. above sea-level. It was occupied by a British force early in 1893, when a determined attack was made on the place by the Kohistanis from the Indus valley districts to the south-west, aided by contingents from Darel and Tangir west of Gilgit and north of the Indus. Its importance consists in its position with reference to the Kashmir-Gilgit route via Astor, which it flanks. It is now connected with Bunji by a metalled road. Chilas is also important from its command of a much shorter and more direct route to Gilgit from the Punjab frontier than that of Kashmir and the Burzil pass. By the Kashmir route Gilgit is 400 m. from the rail-head at Rawalpindi. The Kagan route would bring it 100 m. nearer, but the unsettled condition of the country through which the road passes has been a bar to its general use.
CHILBLAINS (or Kibe; Erythema pernio), a mild form of frostbite, affecting the fingers or toes and other parts, and causing a painful inflammatory swelling, with redness and itching of the affected part. The chief points to be noticed in its aetiology are (1) that the lesions occur in the extremities of the circulation, and (2) that they are usually started by rapid changes from heat to cold or vice versa. The treatment is both general and local. In the general treatment, if a history of blanching fingers (fingers or hands going “dead”) can be obtained, the chilblains may be regarded as mild cases of Raynaud’s disease, and these improve markedly under a course of nitrites. Cardiac tonics are often helpful, especially in those cases where there is some attendant lesion of the heart. But the majority of cases improve wonderfully on a good course of a calcium salt, e.g. calcium lactate or chloride; fifteen grains three times a day will answer in most cases. The patient should wash in soft tepid water, and avoid extremes of heat and cold. In the local treatment, two drugs are of great value in the early congestive stage—ichthyol and formalin. Ichthyol, 10 to 20% in lanoline spread on linen and worn at night, often dispels an attack at the beginning. Formalin is equally efficacious, but requires more skill in its use. It can be used as an ointment, 10 to 50% for delicate skins, stronger for coarser skins. It should be replaced occasionally by lanoline. If the stage of ulceration has been reached, a paste made from the following prescription, spread thickly on linen and frequently changed, soon cures:—Hydrarg. ammoniat. gr. v., ichthyol ɱx, pulveris zinci oxidi ʒiv, vaseline ℥ss.
CHILD, SIR FRANCIS (1642–1713), English banker, was a Wiltshire man, who, having been apprenticed to a goldsmith, became himself a London goldsmith in 1664. In 1671 he married Elizabeth (d. 1720), daughter of another goldsmith named William Wheeler (d. 1663), and with his wife’s stepfather, Robert Blanchard (d. 1681), took over about the same time the business of goldsmiths hitherto carried on by the Wheelers. This was the beginning of Child’s Bank. Child soon gave up the business of a goldsmith and confined himself to that of a banker. He inherited some wealth and was very successful in