was probably deposited upon a basis of fact, and we may believe that the Sakyas suffered much at the hands of Virudhaka.
If the chronology adopted in this chapter be even approximately correct, Bimbisara and Ajatasatru must be regarded as the contemporaries of Darius, the son of Hystaspes, autocrat of the Persian empire from 521 to 485 B.C. Darius, who was a very capable ruler, employed his officers in the exploration of a great part of Asia by means of various expeditions.
One of these expeditions was despatched at some date later than 516 B.C. to prove the feasibility of a passage by sea from the mouth of the Indus to Persia. The commander, Skylax of Karyanda in Karia, managed somehow to equip a squadron on the waters of the Panjab rivers in the Gandhara country, to make his way down to the ocean, and ultimately to reach the Red Sea. The particulars of his adventurous voyage have been lost, but we know that the information collected was of such value that, by utilizing it, Darius was enabled to annex the Indus valley, and to send his fleets into the Indian Ocean. The archers from India formed a valuable element in the army of Xerxes, and shared the defeat of Mardonius at Plataea.
The conquered provinces were formed into a separate satrapy, the twentieth, which was considered the richest and most populous province of the empire. It paid the enormous tribute of 360 Euboic talents of gold-dust, or 185 hundredweights, worth fully a million sterling, and constituting about one-third of the total