light horse was armed with the same sort of bows and arrows as the
heavy, but carried no spear and wore no armor. It was carefully trained
to the management of the horse and the bow, and was unequalled in the
rapidity and dexterity of its movements. The archer delivered his arrows
with as much precision and force in retreat as in advance, and was
almost more feared when he retired than when he charged his foe. Besides
his arrows, the light horseman seems to have carried a sword, and he no
doubt wore also the customary knife in his belt.

We are told by one writer that it was a practice of the Parthians to
bring into battle a number of led horses, and that the riders from time
to time exchanged their tired steeds for fresh ones, thus obtaining a
great advantage over enemies who had no such practice. But the accounts
which we have of Parthian engagements make no reference to this usage,
which we can therefore scarcely suppose to have been adopted to any
large extent. It may be doubted, also, if the practice could ever be
one of much value, since the difficulty of managing led horses amid the
tumult of a battle would probably more than counterbalance the advantage
derivable from relays of fresh steeds.

During the later period of the monarchy, the Parthians, who had always
employed camels largely in the conveyance of stores and baggage, are
said to have introduced a camel corps into the army itself, and to have
derived considerable advantage from the new arm. The camels could bear
the weight of the mailed warrior and of their own armor better than
horses, and their riders were at once more safe in their elevated
position and more capable of dealing effective blows upon the enemy.
As a set-off, however, against those advantages, the spongy feet of
the camel were found to be more readily injured by the _tribulus_, or
caltrop, than the harder feet of the horse, and the corps was thus more
easily disabled than an equal force of cavalry, if it could be tempted
to pass over ground on which caltrops had been previously scattered.

The Parthian tactics were of a simple kind, and differed little from
those of other nations in the same region, which have depended mainly on
their cavalry. To surround their foe, to involve him in difficulties,
to cut off: his supplies and his stragglers, and ultimately to bring him
into a position where he might be overwhelmed by missiles, was the aim
of all Parthian commanders of any military capaci