At the same time they learnt to take full advantage of the Parthian inefficiency against walls, and to practice against them the arts of pretended retreat and ambush.

The result was, that Parthia found she could make no impression upon the dominions of Rome, and, having become persuaded of this by the experience of a decade of years, thenceforth laid aside for ever the idea of attempting Western conquests.

She took up, in fact, from this time, a new attitude, Hitherto she had been consistently aggressive.

She had labored constantly to extend herself at the expense successively of the Bactrians, the Scythians, the Syro-Macedonians, and the Armenians.
She had proceeded from one aggression to another, leaving only short intervals between her wars, and had always been looking out for some fresh enemy.

Henceforth she became, comparatively speaking, pacific.