Kennedy explored the northern tributaries of the Darling, and a river in S.
Below Kuhsan it receives fresh tributaries from the west.
In the north of the department; the Oise, traversing the northwest, with its tributaries the Serre and the Aisne, the latter of which joins it beyond the limits of the department; and the Marne and the Ourcq in the south.
River transport has some local value on the upper Sao Francisco and its larger tributaries, and this will be greatly increased when the Central do Brazil railway reaches the head of navigation on that river.
Dvina, which falls into the sea below Riga, is shallow above the rapids of Jacobstadt, but navigation is carried on as far as Vitebsk - corn, timber, potash, flax, &c., being the principal shipments of its navigable tributaries (the Obsha, Ulla and Kasplya).