134 ALEXANDER'S EASTERN EXPEDITION. [CHAP. In the following spring (329 B.C.), as soon as the season was sufficiently far advanced, Alexander crossed the Invasion of / . , Bactria, Paropamisus—an operation which occupied seven- 329 B'c* teen days—into Bactria, and at once marched to the capital of the province, Bactra (Balkh), which he occupied. The general features of that region are accurately described by Curtius, who speaks of it as in most parts a sandy desert, but interspersed with districts of great fertility1. They (jThoCun)XUS next Cached the Oxus, with which river the Greeks now for the first time became acquainted, and it seems to have made a greater impression upon them than either the Tigris or the Euphrates2. This river—now the Jihoun or Amu Daria—which rises away to the east in a glacier among the mountains of the Pamir3, at the present time finds its way, like the Jaxartes, into the sea of Aral: by the ancients, course.ncient however, who were unacquainted with the existence of that piece of water, they were both believed to reach the Caspian. In the case of the Oxus there is every reason to believe that such was the case in the time of Alexander; and this would account for the statement of Strabo and Pliny—quot- ing from independent sources—that a regular trade-route existed from India to Europe by way of this river and of the Caspian and Euxine Seas4. After crossing the Oxus, the conqueror 1 Curt, 7. 4. 26—30. 2 Arrian, 3. 29. i; 6 8£ *J2£os ftci t^v At roO fipous rod Kavicdtrov, fort 8t Trorajuwv /^ytorros rQv fr rj} 'Av)