period of time, he gives the leader of the Greeks a thong with sixty knots. The calendars of the Persians and Greeks were different; there were variations in the calendars of the Aeolians, Ionians, and Dorians; but sixty days could have been fixed without a strap and knots. Beyond the Danube Darius blindly follows the division of Scopasis, wherever it leads him away to the east and north as far as the Volga. On what did the army of Darius subsist--and it numbered 700,000 men, or if we include the train, it reached a total of about a million--for more than two months in a country in which, according to Herodotus' own statement, there was no tilled land except at the mouths of the Bug and Dnieper, and in which the advancing Scythians had destroyed the wells and pastures, as Herodotus asserts? How did the Persians cross the Tyras (Dniester), Hypanis (Bug), Borysthenes (Dnieper), and the Tanais (Don)? From whence did they procure the wood for the bridges or rafts for crossing them, in the steppe which Herodotus rightly describes as entirely without wood down to the forests on the southern edge? Whence came the water for man and beast in the waterless desert? When Darius had crossed the Don Herodotus represents him as building eight large fortresses beyond the river on the bank of the Volga, the object of which it is impossible to discover; and in a space of a little more than two months he represents the Persian army as not only building these forts but marching round the whole territory of Scythia, which in his description extends for 500 miles from the mouth of the Danube to the mouth of the Don, and an equal distance northwards into the land, and even far beyond it. Darius marches as far as the Volga on the east, and northwards to the desert which lies beyond the Sarmatians (whose territory extends for fifteen days' journey up the Don),[270] and also beyond the Budini, "a great and numerous people," and the Geloni (p. 275). From this point he returns, according to Herodotus, through the territory of the northern neighbours of the Scythians to the west, as far as the lake out of which the Tyras (Dniester) rises, till the Scythians, who are a day's march in advance of the Persians, reach the land of the Agathyrsi. According to Herodotus' reckoning of the distances, Darius traversed a journey of about a hundred days' marches of twenty-five miles each, in less than fifty days. If Herodotus allows the region of the Scoloti to extend too far to the north, if on the Dnieper it reached only to the rapids of the stream, where the tombs of the Scythian kings lay, the distance, on the other hand, from the mouth of the Danube to the Don, on which the Scoloti and the Sarmatians bordered, and which Darius is said to have crossed, was far greater than Herodotus assumes; it is at least 750 miles, and from the mouth of the Danube to the Volga at least 900 miles, which on the route taken by Darius could not possibly have been traversed both ways in eighty or