Which is bounded on the north by the government of St. Paul, in Brazil; on the north-west by the river Parana, which divides it from Paraguay; on the west by the plains of Tucuman; on the east by the Portuguese frontier, which passes south through lake Mini; on the south-west, by the Atlantic Ocean, and the line of demarcation between it and the independent tribes; on the south-east by Cuyo, and on the south, by an imaginary line, passing through the Pampas or Patagonia. _History, &c._--The history of this government is that of the viceroyalty; the most extraordinary part of it being that which relates to the subjugation of the Indians by the Jesuits, who established their principal stations in the country, embraced by the Parana on the north, the Uruguay on the east; and the La Plata on the west and south. The road for these missionaries was prepared by Alvar Nuñez de Vaca, in 1541, who conquered the country, and named it Vera. Two monks of the order of St. Francis accompanied the governor in his expedition, and laboured very hard to convert the natives, which they succeeded so well in, that others of the same order were soon established in the country, in which they erected chapels and villages. Of these monks, Father Luis de Bolaños was the most zealous; he stayed fifty years among the Guaranies, and made himself master of their language; at last, bent down with age and fatigue, he went to welcome the arrival of some Jesuit brothers, who came to assist him in his labours; these were with difficulty admitted into the country, owing to the aversion of the natives to have any other pastor than the venerable Bolaños. From this time the Jesuits laboured so effectually to convert the Indians, that in a very short period, the greater part of the country was in their power; they extended their dominion over Paraguay, and organized the Indians into a well disciplined body of militia, by which means they kept all persons, whether Spaniards or Portuguese, out of their territories. From Paraguay and Parana, they drew such great revenues, by making their converts work at stated periods in the plantations, &c., that they were enabled not only to supply every thing necessary for the comfort of the people from Europe, but were also enabled to send immense sums to the superiors of their order. The Indians were studiously kept in ignorance of the Spanish language; they were instructed in all sorts of useful arts, and sedulously trained to the fatigues of a military life, being formed into large bodies of cavalry and infantry, and well supplied with arms and ammunition. Some hundred thousand of Americans were already under the power, and infatuated in their subjection to these fathers, when in 1750, the courts of Madrid and Lisbon, entered into a treaty for the purpose of definitively fixing the boundaries of their respective possessions in the western world.