Depth shown by soundings. River currents shown in miles per hour. Major tributaries are shown. "The blue line indicates the course of the river according to the best previous Maps." Includes inset: Continued from the map of Spix and Martius to Para [scale ca. 1:6,666,000]. Tribes are located and their approximate population size is given. From: The Journal of the Royal Geographical Society of London. Vol. 6, (1836), pp. 11-23; held in Firestone Library. Call number: G7 .J687 v.6 1836.