Its population can never have been great, and they were at no time aggressive or enterprising, so that on this side also the Parthians were secure, and had to deal with no formidable neighbor. Sagartia succeeded to Sarangia towards the west, and bordered Parthia along almost the whole of its southern frontier.

Upon the south-east Parthia was bordered by Sarangia, the country of the Sarangae, or Drangae. This appears to have been the district south of the Herat valley, reaching thence as far as the Hamoon, or Sea of Seistan. It is a country of hills and downs, watered by a number of somewhat scanty streams, which flow south-westward from the Paropamisus to the Hamoon.

We are further informed by ancient writers that Drangiana, or Sarangia, furnished the rare and valuable mineral tin, without which copper could not be hardened into bronze; that Armenia yielded emery, so necessary for the working and polishing of gems; that the mountains and mines of the Empire supplied almost all the varieties of useful and precious stones; and that thus there was scarcely a mineral known to and required by the ancients for the purposes of their life which the Great King could not command without having recourse to others than his own subjects.

The countries by which Parthia Proper was bounded were the following: Chorasmia, Margiana, Aria, Sarangia, Sagartia, and Hyrcania. Chorasmia lay upon the north, consisting of the low tract between the most northerly of the Parthian mountain chains and the old course of the Oxus.

In the inscriptions of this king we find their country included under the name of Parthva or Parthwa among the provinces of the Persian Empire, joined in two places with Sarangia, Aria, Chorasmia, Bactria, and Sogdiana, and in a third with these same countries and Sagartia. We find, moreover, an account of a rebellion in which the Parthians took part.