It is a matter of wonder to this day how the Jesuit Fathers, even taking into consideration their unquenchable zeal and marvelous energy and determination, ever succeeded in reaching so isolated a territory and in traversing it in every direction, as they did, in pursuit of their campaign. Even to-day it is well-nigh impossible to reach the heart of the region—the great cataract of Guayra, which, hundreds of miles from the habitations of man, isolated by jagged mountains, fiercely swirling waters and the wild tangle of underbrush that make headway through the awesome tropical forest very difficult, constitutes one of the most majestic of nature’s wonder-works in South America. Situated about a hundred miles up the Paraná River from the better known Iguazú Falls, the Guayra cataract lies on the frontier with Brazil. A volume of water twice as large as that which thunders over Niagara is forced through a gorge two hundred feet wide from a stream two and a half miles in width. The roar of its plunge of fifty-six feet to the lower levels, adds the essential note to this tremendous symphony of primeval nature. Outside the Arctic regions, one explorer declares, no part of the world is less accessible than the Paraná above the Great Cataract. After the expulsion of the Jesuits the Paraná basin reverted to forest and the nation pursued its checkered career in the section drained by the Paraguay. This river intersects the republic from north to south and is navigable through its entire course by ocean steamers, which pass up from Buenos Aires through the Paraná, and past Corrientes, where the two great streams join forces. On the left bank of the Paraguay, at the point of its confluence with the equally great Pilcomayo, the traveler comes to the ancient city of Asunción, the capital of the country. Here was the seat of the colonial authority over Plata settlements until Buenos Aires grew into importance. It has a population of 52,000, and is now thriving and prosperous, rapidly taking on the cosmopolitanism that characterizes the other ports of South America. The capital, and indeed the whole country has but recently entered into a new life, a life as sharply contrasted with its period of political storm and stress as the transition was sudden.