territorial extent was equal to half of modern Europe. It touched
the waters of the Mediterranean, the Aegean, the Black, the
Caspian, the Indian, the Persian, the Red Seas. Through its
territories there flowed six of the grandest rivers in the
world--the Euphrates, the Tigris, the Indus, the Jaxartes, the
Oxus, the Nile, each more than a thousand miles in length. Its
surface reached from thirteen hundred feet below the sea-level to
twenty thousand feet above. It yielded, therefore, every
agricultural product. Its mineral wealth was boundless. It
inherited the prestige of the Median, the Babylonian, the
Assyrian, the Chaldean Empires, whose annals reached back through
more than twenty centuries.

THE PERSIAN EMPIRE. Persia had always looked upon European Greece
as politically insignificant, for it had scarcely half the
territorial extent of one of her satrapies. Her expeditions for
compelling its obedience had, however, taught her the military
qualities of its people. In her forces were incorporated Greek
mercenaries, esteemed the very best of her troops. She did not
hesitate sometimes to give the command of her armies to Greek
generals, of her fleets to Greek captains. In the political
convulsions through which she had passed, Greek soldiers had
often been used by her contending chiefs. These military
operations were attended by a momentous result. They revealed,
to the quick eye of these warlike mercenaries, the political
weakness of the empire and the possibility of reaching its
centre. After the death of Cyrus on the battle-field of Cunaxa,
it was demonstrated, by the immortal retreat of the ten thousand
under Xenophon, that a Greek army could force its way to and from
the heart of Persia.