[15] Having given these instructions, Cyrus assigned a body of troops to each of his satraps, and sent them out to their provinces, bidding them to be ready for a campaign in the new year and for a review of their soldiers, their weapons, their horses, and their chariots.

[16] And here I may notice another custom, also instituted by Cyrus, it is said, and still in force to-day: every year a progress of inspection is made by an officer at the head of an army, to help any satrap who may require aid, or bring the insolent to their senses; and, if there has been negligence in the delivery of tribute, or the protection of the inhabitants, or the cultivation of the soil, or indeed any omission of duty whatsoever, the officer is there to put the matter right, or if he cannot do so himself, to report it to the king, who decides what is to be done about the offender.

The announcements so often made, such as "the king's son is coming down," or "the king's brother," or "the king's eye," refer to these inspectors, but sometimes no one appears, for at any moment the officer may be turned back at the king's command.

[17] We hear of another arrangement, devised to meet the huge size of the empire and enable the king to learn with great celerity the state of affairs at any distance.

Cyrus first ascertained how far a horse could travel in one day without being over-ridden, and then he had a series of posting-stations built, one day's ride apart, with relays of horses, and grooms to take care of them, and a proper man in charge of each station to receive the despatches and hand them on, take over the jaded horses and men, and furnish fresh ones.