I must here boldly borrow Sir H. H. Risley's summary of the historical record of Scythian invasions into India, since that is the main justification for his theory. "In the time of the Achaemenian kings of Persia," he says, "the Scythians, who were known to the Chinese as Sse, occupied the regions lying between the lower course of the Sillis or Jaxartes and Lake Balkash. The fragments of early Scythian history which may be collected from classical writers are supplemented by the Chinese annals, which tell us how the Sse, originally located in southern China, occupied Sogdiana and Trans-oxiana at the time of the establishment of the Graeco-Bactrian monarchy. Dislodged from these regions by the Yueh-chi, who had themselves been put to flight by the Huns, the Sse invaded Bactriana, an enterprise in which they were frequently allied with the Parthians. To this circumstance, Ujfalvy says may be due the resemblance which exists between the Scythian coins of India and those of the Parthian kings. At a later period, the Yueh-chi made a further advance, and drove the Sse or Sakas out of Bactriana, whereupon the latter crossed the Paropamisus and took possession of the country called after them Sakastān, comprising Segistān, Arachosia, and Drangiana. But they were left in possession only for a hundred years, for about 25 B.C. the Yueh-chi disturbed them afresh. A body of Scythians then emigrated eastwards, and founded a kingdom in the western portion of the Panjāb. The route they followed in their advance upon India is uncertain; but to a people of their habits it would seem that a march through Baluchistan would have presented no serious difficulties.