Thirty miles north of the mouth of the Crixa, which is also navigable, and has some salt pits in its vicinity, the Araguaya divides itself in the latitude of 12° 30′ into two branches nearly equal, which re-unite themselves in the parallel of 9° 36′, having formed the island of St. Anna, otherwise Bannanal, of one hundred and eighty miles in length, and of good width: there is a vast lake in the island which has an outlet into an arm of this river. The western arm preserves the name of Araguaya, and the eastern takes that of Furo, by which latter navigators commonly proceed. Both have falls, and a great number of islands, generally small, flat, and for the most part inundated during the periodical rains. The margins of the Furo are lower than those of the other arm, which latter receives by the western side various rivers, with which it is greatly augmented. The principal is the Mortes, which flows from the centre of Bororonia with near three hundred miles of course, and empties itself about forty miles north of the southern point of the island of St. Anna. At the northern extremity of this island the margins of the Araguaya are elevated a little to the confluence of that river with the Tucantines. The first navigators placed this confluence in 6°, the geographers of Para in 5°, and others in 3° 30′; the medium is evidently nearest the truth.

The river Corumba has its origin in the proximity of that of the river Almas, not far distant from the Montes Pyreneos. Its course for a vast space describes a large semicircle to the east (where it receives, amongst others, the river St. Bartholomew) as far as the parallel of its source, where the river Peixe is incorporated with it by the right. Thirty miles lower the river Verissimo unites itself with it on the left, after an extensive course, bringing the waters of another called Braco do Verissimo. From hence it flows for a considerable extent, and loses its name on falling into the Parannahiba, which constitutes a boundary for some miles to the province of Minas Geraes as far as the mouth of the river St. Marcos, its northern head, and which makes a similar divisionary line in the opposite direction.

Below the embouchure of the Corumba, the Parannahiba is joined by the large river Velhas, the principal head of which is near that of the Andayha, on the borders of Minas Geraes. Many leagues below the mouth of the river Velhas is the confluence of the Parannahiba with the Rio Grande, the limit of the province. In the vicinity of the embouchure of the Velhas, the Parannahiba receives on the right the Annicuns, the most considerable amongst those which unite themselves with it on that side, and has its source in the large wood of Matto Grosso previously mentioned.

Almost all the povoaçoes or inhabited places of this province already existed when it was so created and delivered to the government of the viceroy, Conde d’Arcos; and all of them, excepting those in the southern districts, owe their foundation to the gold sought after upon their sites and surrounding lands.

The jurisdiction of the ouvidor extended over the whole province, until the present King, when Prince Regent, by a decree of the 18th of March, 1809, divided it into two comarcas, the new one taking the name of St. Joam das Duas Barras, the other retaining that of the capital. Each of them comprehends eight julgados, or divisions, including the district of the capital, the only povoaçao yet enjoying the title of a town.

The comarca of Villaboa comprises the following julgados:—

The comarca of St. Joam das Duas Barras the following:—

The above division of the province points out the jurisdiction of each comarca, but does not assist to form a correct idea of the country, in consequence of the great inequality which prevails in their extent and population; for instance, the julgado of the capital is upwards of five hundred miles long from north to south, and of proportionable width, and the julgado of Conceiçao extends east and west from one boundary of the province to the other; whilst that of Pilar is not more than one hundred miles long, and those of Desemboque and Araxa are much smaller.