[Illustration: EARLY SPANISH MAP OF PERU. [From the Paris (1774) edition of Zarate. The development of Peruvian cartography under the Spanish explorations is traced in a note in Vol. II. p. 509; but the best map for the student is a map of the empire of the Incas, showing all except the provinces of Quito and Chili, with the routes of the successive Inca conquerors marked on it, given in the _Journal of the Roy. Geog. Soc._ (1872), vol. xlii. p. 513, compiled by Mr. Trelawny Saunders to illustrate Mr. Markham’s paper of the previous year, on the empire of the Incas. The map was republished by the Hakluyt Society in 1880. The map of Wiener in his _Pérou et Bolivie_ is also a good one. Cf. Squier’s map in his _Peru_.—ED.]] The nature of the country and climate was a potent agent in forming the character of the people, and in enabling them to make advances in civilization. In the dense forests of the Amazonian valleys, in the boundless prairies and savannas, we only meet with wandering tribes of hunters and fishers. It is on the lofty plateaux of the Andes, where extensive tracts of land are adapted for tillage, or in the comparatively temperate valleys of the western coast, that we find nations advanced in civilization.[1141] The region comprised in the empire of the Incas during its greatest extension is bounded on the east by the forest-covered Amazonian plains, on the west by the Pacific Ocean, and its length along the line of the Cordilleras was upwards of 1,500 miles, from 2° N. to 20° S. This vast tract comprises every temperature and every variety of physical feature. The inhabitants of the plains and valleys of the Andes enjoyed a temperate and generally bracing climate, and their energies were called forth by the physical difficulties which had to be overcome through their skill and hardihood. Such a region was suited for the gradual development of a vigorous race, capable of reaching to a high state of culture. The different valleys and plateaux are separated by lofty mountain chains or by profound gorges, so that the inhabitants would, in the earliest period of their history, make their own slow progress in comparative isolation, and would have little intercommunication. When at last they were brought together as one people, and thus combined their efforts in forming one system, it is likely that such a union would have a tendency to be of long duration, owing to the great difficulties which must have been overcome in its creation. On the other hand, if, in course of time, disintegration once began, it might last long, and great efforts would be required to build up another united empire. The evidence seems to point to the recurrence of these processes more than once, in the course of ages, and to their commencement in a very remote antiquity.