en the mountains, the river, and the sea, the
numbers of the Persians confused and clogged alike the general's skill
and the soldiers' prowess, and their very strength had been made their
weakness. Here, on the broad plains of Kurdistan, there was scope for
Asia's largest host to array its lines, to wheel, to skirmish, to
condense or expand its squadrons, to manoeuvre, and to charge at will.
Should Alexander and his scanty band dare to plunge into that living sea
of war, their destruction seemed inevitable.

Darius felt, however, the critical nature to himself as well as to his
adversary of the coming encounter. He could not hope to retrieve the
consequences of a third overthrow. The great cities of Mesopotamia and
Upper Asia, the central provinces of the Persian empire, were certain to
be at the mercy of the victor. Darius knew also the Asiatic character
well enough to be aware how it yields to _prestige_ of success and the
apparent career of destiny. He felt that the diadem was now either to be
firmly replaced on his own brow or to be irrevocably transferred to the
head of his European conqueror. He, therefore, during the long interval
left him after the battle of Issus, while Alexander was subjugating
Syria and Egypt, assiduously busied himself in selecting the best troops
which his vast empire supplied, and in training his varied forces to act
together with some uniformity of discipline and system.

The hardy mountaineers of Afghanistan, Bokhara, Khiva, and Tibet were
then, as at present, far different from the generality of Asiatics in
warlike spirit and endurance. From these districts Darius collected
large bodies of admirable infantry; and the countries of the modern
Kurds and Turkomans supplied, as they do now, squadrons of horsemen,
hardy, skilful, bold, and trained to a life of constant activity and
warfare. It is not uninteresting to notice that the ancestors of our own
late enemies, the Sikhs, served as allies of Darius against the
Macedonians. They are spoken of in Arrian as Indians who dwelt near
Bactria. They were attached to the troops of that satrapy, and their
cavalry was one of the most formidable forces in the whole Persian army.

Besides these picked troops, contingents also came in from the numerous
other provinces that yet obeyed the Great King. Altogether, the horse
are said to have been forty thousand, the scythe-bearing chariots two
hundred, and the armed elephants fifteen in number. The amoun