ther, but one that does not appear to have been suggested
till too late, was that which Alexander had taken against Darius; the
line along the foot of the Mons Masius, by Edessa, and Nisibis,
to Nineveh. Here too waters and supplies would have been readily
procurable, and by clinging to the skirts of the hills the Roman
infantry would have set the Parthian cavalry at defiance. Between these
two extreme courses to the right and to the left were numerous slightly
divergent lines across the Mesopotamian plain, all shorter than either
of the two above-mentioned, and none offering any great advantage over
the remainder.

It is uncertain what choice the proconsul would have made, had the
decision been left simply to his own judgment. Probably the Romans had a
most dim and indistinct conception of the geographical character of the
Mesopotamian region, and were ignorant of its great difficulties.
They remained also, it must be remembered, up to this time, absolutely
unacquainted with the Parthian tactics and accustomed as they were to
triumph over every enemy against whom they fought, it would scarcely
occur to them that in an open field they could suffer defeat. They were
ready, like Alexander, to encounter any number of Asiatics, and only
asked to be led against the foe as quickly as possible. When, therefore,
Abgarus, the Osrhoene prince, soon after Crassus had crossed the
Euphrates, rode into his camp, and declared that the Parthians did not
intend to make a stand, but were quitting Mesopotamia and flying with
their treasure to the remote regions of Hyrcania and Scythia, leaving
only a rear guard under a couple of generals to cover the retreat, it is
not surprising that the resolution was taken to give up the circuitous
route of the Euphrates, and to march directly across Mesopotamia in the
hope of crushing the covering detachment, and coming upon the flying
multitude encumbered with baggage, which would furnish a rich spoil to
the victors. In after times it was said that C. Cassius Longinus and
some other officers were opposed to this movement, add foresaw its
danger; but it must be questioned whether the whole army did not readily
obey its leader's order, and commence without any forebodings its march
through Upper Mesopotamia. That region has not really the character
which the apologists for Roman disaster in later times gave to it. It
is a region of swelling hills, and somewhat dry gravelly plains. It
possesses several