The Río Negro and the Jupura are two tributaries of the Amazon comparable in length to the Danube, whose upper parts belong to Spain and whose lower reaches are occupied by Portugal. In these majestic rivers people have gathered in those places where civilization is most ancient. The banks of the Upper Jupura or Caqueta have been cultivated by missionaries who came down from the mountains of Popayan and Neiva. From Mocoa to the confluence with Caguan there are many Christian settlements, while in the Lower Jupura the Portuguese have founded hardly a few villages. Along the Río Negro, on the other hand, the Spaniards have not been able to rival their neighbors. How can they rely on a people so distanced from has the province of Caracas? Steppes and virtually deserted jungle some 160 leagues thick separate the cultivated parts of the river bank from the four missions of Maroa, Tomo, Davipe and San Carlos.