PIAUHI, or PIAUHY, a province of Brazil, bounded on the N. by the Atlantic, E. by the provinces of Ceará and Pernambuco, S. by those of Bahia and Goyaz, and W. by that of Maranhão, lies between S. Lat. 2. 42. and 11. 20., W. Long. 40. 30. and 47. The length of the coast-line is little more than 60 miles; but the province stretches inland for about 400 miles, and has a very considerable breadth in the interior. Its area is 169,668 square miles. On the E. and S. frontiers it is bounded by mountain ranges; the Serra Habiapaba separating it from Ceará, and the Cordilera de Borborema from Pernambuco. From these mountains the country gradually slopes towards the bed of the Parnaíba, the only large river in the province, which it separates from that of Maranhão. The river Piauihi, from which the province derives its name, originates in the southern frontier, and, running northward through pasture lands, enters the Caninde, an affluent of the Parnaíba, 50 miles below Oeiras, the capital, after a course of 140 miles. There are no serras of any consequence, nor any large forests, in this province. It consists of vast grassy plains, little wooded, but in which numerous tall herbs attest the bounty of the sun. Originally the province was explored and subdued on account of its pastures, and not for the sake of slaves or from its possessing mines of the precious minerals or metals, for in these it appears to be deficient. Iron, lead, silver, and other minerals are found, but very little worked. Horses and cattle still form the chief riches of the country. It is to Piauihi that the neighbouring provinces of Pernambuco, Maranhão, Bahia, and Minas Geraes look chiefly for their supply of cattle. Piauihi occasionally suffers greatly from drought; but the evils consequent thereupon are much ameliorated by the presence of several trees which yield abundance of grateful and wholesome juices. The climate is warm and dry; and the soil, being generally flat and fertile, is well adapted for cultivation. Rice, tobacco, and sugar are raised near the rivers and lakes, where abundance of water can be obtained; and in the more arid regions millet, mandioca, and cotton are grown. The only seaport in the province is Parnaíba, on a branch of the river of the same name, where some trade is carried on in hides and cotton. Oeiras, the capital, stands on a small tributary of the Caninde, 320 miles S.S.E. of Maranhão. It is small, with broad but unpaved streets,
and neat whitewashed houses, and contains several churches and schools. It is the seat of the provincial legislature, of the governor of Piauihi, and other officials. Some trade is carried on in cattle and agricultural produce. Pop. (with the surrounding district) 6000. Piauihi is divided into six comarcas. It has a provincial assembly of twenty-eight members, and appoints to the general legislature of Brazil one senator and two deputies. Pop. (1856) 150,400.