It is not clear from the account of Megasthenes, or at any rate from the excerpts which have come down to us, what was the extent of the period which elapsed between the last interruption in the list of kings and Sandrakottos. Hence we are not in a position to ascertain the duration of the fourth age, or Kaliyuga, as it was fixed among the Indians in his time; we must therefore have recourse to other proofs in order to discover whether the year given in the Puranas, 3102 B.C., may be taken for the commencement of a new period, _i.e._ the post-epic, or historic, in the valley of the Ganges. The fixed point from which we must start is the year of the accession of Sandrakottos, a date rendered certain by the accounts of the Greeks. In the period before this date, the lists of the Brahmans taken together with the lists of Buddhists carry back the series of the kings of Magadha, which was the most important kingdom on the Ganges long before Sandrakottos, with tolerable certainty as far as the year 803 B.C., _i.e._ to the beginning of the sway of the dynasty of the Pradyotas over Magadha.[132] Can we ascend beyond this point? According to the Puranas, the race of the Barhadrathas had ruled over Magadha before the Pradyotas, from Somapi to Ripunjaya, the last of the family, and their sway had continued 1000 years. Of this family the Vayu-Purana enumerates 21 kings, and the Matsya-Purana 32 kings. This domination of a thousand years is obviously a round, cyclic sum: and both in the Vayu-Purana and the Matsya-Purana the total of the reigns given for the several rulers of this dynasty falls below the sum of 1000 years. If we take 25 years, the highest possible average for each reign, 21 reigns or 525 years will only bring us to the year 1328 B.C. (803 + 525). At this date, then, the Barhadrathas may have begun to reign over Magadha. If, on the other hand, we keep 32 as the number of these kings, and an average of only 15 years is allotted to the several reigns--an average usually correct in long lists of reigns in the East--we arrive at 1283 B.C. as the date of the beginning of the reign of the Barhadrathas (803 + 480). To this date, or near it, we come, if we test the lists of kings supplied by the Puranas for the series of the kings of the Koçalas and the Bharatas in the land of the Ganges. The time at which Prasenajit was king of the Koçalas can be fixed at the first half of the sixth century B.C. (see below). Before him the Vishnu-Purana gives a series of 23 kings down to the close of the great war. Twenty-three reigns, allowing an average of 25 years for each, carry us 575 years beyond the commencement of Prasenajit, _i.e._ up to 1175 B.C. (600 + 575). In the list of the rulers of Hastinapura, for which throne the great war was waged, Çatanika appears as the twenty-fourth successor of Parikshit, to whom, as we found, this throne fell, after the conclusion of the great war. As Çatanika died about the year 600 B.C. (cf. Book VI. chap, i.), 24 reigns