Hyrcania is traversed by the rivers Ochus and Oxus to their outlets into the sea; and of these, the Ochus flows also through Nesaea, but some say that the Ochus empties into the Oxus. Aristobulus1
declares that the Oxus is the largest of the rivers he has seen in Asia, except those in India. And he further says that it is navigable (both he and Eratosthenes taking this statement from Patrocles)2
and that large quantities of Indian wares are brought down on it to the Hyrcanian sea, and thence on that sea are transported to Albania and brought down on the Cyrus River and through the region that comes next after it to the Euxine. The Ochus is not mentioned at all by the ancient writers. Apollodorus,3
however, who wrote the Parthica
, names it continually, implying that it flows very close to the country of the Parthians.