their faces
the autograph letter of their master; while, according to another, he
responded, with a contemptuous smile, that "there was no occasion for
an exchange of thought between him and the Persian king by messengers,
since he intended very shortly to treat with him in person." Having
received this rebuff, the envoys of Sapor took their departure, and
conveyed to their sovereign the intelligence that he must prepare
himself to resist a serious invasion.

About the same time various offers of assistance reached the Roman
emperor from the independent or semi-independent princes and chieftains
of the regions adjacent to Mesopotamia. Such overtures were sure to
be made by the heads of the plundering desert tribes to any powerful
invader, since it would be hoped that a share in the booty might be
obtained without much participation in the danger. We are told that
Julian promptly rejected these offers, grandly saying that it was for
Rome rather to give aid to her allies than to receive assistance from
them. It appears, however, that at least two exceptions were made to the
general principle thus magniloquently asserted. Julian had taken into
his service, ere he quitted Europe, a strong body of Gothic auxiliaries;
and, while at Antioch, he sent to the Saracens, reminding them of their
promise to lend him troops, and calling upon them to fulfil it. If
the advance on Persia was to be made by the line of the Euphrates,
an alliance with these agile sons of the desert was of first-rate
importance, since the assistance which they could render as friends was
considerable, and the injury which they could inflict as enemies was
almost beyond calculation. It is among the faults of Julian in this
campaign that he did not set more store by the Saracen alliance, and
make greater efforts to maintain it; we shall find that after a while
he allowed the brave nomads to become disaffected, and to exchange their
friendship with him for hostility. Had he taken more care to attach them
cordially to the side of Rome, it is quite possible that his expedition
might have had a prosperous issue.

There was another ally, whose services Julian regarded himself as
entitled not to request, but to command. Arsaces, king of Armenia,
though placed on his throne by Sapor, had (as we have seen) transferred
his allegiance to Constantius, and voluntarily taken up the position of
a Roman feudatory. Constantius had of late suspected his fidelity; but
Arsaces