been
truly characterized as one "the like of which is not to be found in
Eastern history, and has scarcely been imagined in Eastern romance,"
yet, allowing much for exaggeration, we may still safely conclude that
great exertions had been made on the Persian side, that their forces
consisted of the three arms mentioned, and that the numbers of each
were large beyond ordinary precedent. The two adversaries were thus not
ill-matched; each brought the flower of his troops to the conflict; each
commanded the army, on which his dependence was placed, in person;
each looked to obtain from the contest not only an increase of military
glory, but substantial fruits of victory in the shape of plunder or
territory.

It might have been expected that the Persian monarch, after the high
tone which he had taken, would have maintained an aggressive attitude,
have crossed the Euphrates, and spread the hordes at his disposal over
Syria, Cappadocia, and Asia Minor. But it seems to be certain that he
did not do so, and that the initiative was taken by the other side.
Probably the Persian arms, as inefficient in sieges as the Parthian,
were unable to overcome the resistance offered by the Roman forts upon
the great river; and Artaxerxes was too good a general to throw his
forces into the heart of an enemy's country without having first secured
a safe retreat. The Euphrates was therefore crossed by his adversary
in the spring of A.D. 232; the Roman province of Mesopotamia was easily
recovered; and arrangements were made by which it was hoped to deal the
new monarchy a heavy blow, if not actually to crush and conquer it.

Alexander divided his troops into three bodies. One division was to
act towards the north, to take advantage of the friendly disposition
of Chosroes, king of Armenia, and, traversing his strong mountain
territory, to direct its attack upon Media, into which Armenia gave a
ready entrance. Another was to take a southern line, and to threaten
Persia Proper from the marshy tract about the junction of the Euphrates
with the Tigris, a portion of the Babylonian territory. The third and
main division, which was to be commanded by the emperor in person, was
to act on a line intermediate between the other two, which would conduct
it to the very heart of the enemy's territory, and at the same time
allow of its giving effective support to either of the two other
divisions if they should need it.

The plan of operations appears to have