MADRID, a province of Spain, one of the five into which New Castile is divided, is bounded on the W., N.W., and N. by Avila and Segovia, on the E. by Guadalajara, on the S.E. by Cuenca, and on the S. by Toledo. The area is 2997 square miles, with a population in 1877 of 593,775, an increase of 104,443 since 1860. Madrid belongs to the basin of the Tagus, being separated from that of the Douro by the Sierra Guadarrama, which skirts the province on the north-west and north. The Tagus itself is the southern boundary for some distance, its chief tributary being the Jarama, which rises in the Somosierra in the north, and terminates at Aranjuez. The Jarama, in turn, is joined by the Henares and Tajuña on the left, and by the Lozoya and Manzanares on the right. The Guadarrama, another tributary of the Tagus, has its upper course within the province. Like the rest of Castile, Madrid is chiefly of Tertiary formation; the soil is mostly clayey, and there are sandy tracts. Agriculture is in a somewhat backward condition; the rainfall is deficient, and the rivers, poor though they are, are not utilized as they might be for irrigation. The chief products are wheat, barley, rye, oats, algarrobas (Ervum tetraspermum), pease, chick pease, and various other legumes, wine, oil, flax, hemp, wax, honey, and various fruits. Gardening is carried on to some extent near the capital, though the markets of Madrid receive their most liberal supply of fruits and vegetables from Valencia. Sheep, goats, and horned cattle are reared, and fish are found in the Jarama and other rivers. The province is on the whole treeless ; but some wood is grown on the mountain slopes in the north. The Sierra Guadarrama has quarries of granite, lime, and gypsum, and is known to contain iron, copper, and argentiferous lead, but these resources are as yet undeveloped. The manufactures are trifling (coarse cloth, leather, paper, earthenware, porcelain, bricks and tiles, saltpetre, glass and crystal, chocolate, lace); and there is very little commerce beyond that for the supply of the capital with necessaries. The only towns with a population above 10,000 are Alcalá (Complutum) on the Henares, and Madrid; the famous university of the former was trans-ferred to the latter in 1836. Aranjuez (8154), on the Tagus, is also of historical importance.