It had the loose organization of modern Bashi-Bazouks or Cossacks; it hung in clouds on the enemy--assailed, retreated, rallied, re-advanced--fled, and even in flight was formidable, since each rider was trained to discharge his arrows backwards with a sure aim.
against the pursuing foe.

The famous skill of the Parthians in their horse-combats was inherited from their Persian predecessors, who seem to have invented the practice which the later people carried to perfection.
Though mainly depending for success on their numbers, the Persians did not wholly despise the use of contrivance and stratagem.

At Arbela, Darius Codomannus had spiked balls strewn over the ground where he expected the Greek cavalry to make its attacks.

[PLATE XXX., Fig.

5]; and, at Sardis, Cyrus obtained his victory over the Lydian horse by frightening them with the grotesque and unfamiliar camel.