Silk was immediately delivered to the Romans by the Persian merchants, who frequented the fairs of Armenia and Nisibis; but this trade, which in the intervals of truce was oppressed by avarice and jealousy, was totally interrupted by the long wars of the rival monarchies.

The great king might proudly number Sogdiana, and even _Serica_, among the provinces of his empire; but his real dominion was bounded by the Oxus and his useful intercourse with the Sogdoites, beyond the river, depended on the pleasure of their conquerors, the white Huns, and the Turks, who successively reigned over that industrious people.

Yet the most savage dominion has not extirpated the seeds of agriculture and commerce, in a region which is celebrated as one of the four gardens of Asia; the cities of Samarcand and Bochara are advantageously seated for the exchange of its various productions; and their merchants purchased from the Chinese, the raw or manufactured silk which they transported into Persia for the use of the Roman empire.

In the vain capital of China, the Sogdian caravans were entertained as the suppliant embassies of tributary kingdoms, and if they returned in safety, the bold adventure was rewarded with exorbitant gain.

But the difficult and perilous march from Samarcand to the first town of Shensi, could not be performed in less than sixty, eighty, or one hundred days: as soon as they had passed the Jaxartes they entered the desert; and the wandering hordes, unless they are restrained by armies and garrisons, have always considered the citizen and the traveller as the objects of lawful rapine.