Peru is bounded on the north by the southern provinces of Quito,
Maynas, Jaen de Bracamaros, and Guayaquil; on the west by the Pacific
Ocean; on the east, by the Portuguese possessions, and the provinces
of Buenos Ayres; and on the south, by the government of Chili and the
viceroyalty of La Plata. It was formerly the most extensive kingdom
of South America, but in the year 1718 the provinces of Quito in the
north, as far as the river Tumbez, were annexed to the government of
New Granada, and in 1778, Potosi, and several other of its richest
districts on the east were annexed to the viceroyalty of Buenos Ayres;
its present extent is therefore from the Rio Tumbez, in 3° 30'
south latitude, to the chain of Vilcanota, in 15° south latitude,
or 690 geographical miles, while along its coast this length maybe
prolonged to 375 more; its medial breadth, not including the Pampas
del Sacramento, is nearly eighty, so that its area may be estimated at
33,630 square leagues, or according to Humboldt, only at 30,000.
Its eastern settlements bound on Colonna, or the land of the Missions,
the Pampas del Sacramento, and the savage nations of the Pajonal, a
vast steppe covered with long grass.