have supposed that
besides these works there was further built at the same time a great
wall which extended entirely across the tract between the two rivers--a
huge barrier a hundred feet high and twenty thick--meant, like the Roman
walls in Britain and the great wall of China, to be insurmountable by an
unskillful foe; but there is ground for suspecting that this belief is
ill-founded, having for its sole basis a misconception of Xenophon's.

Nabonadius appears to have been allowed ample time to carry out to the
full his system of defences, and to complete all his preparations.
The precipitancy of Croesus, who plunged into a war with Persia
single-handed, asking no aid from his allies, and the promptitude of
Cyrus, who allowed him no opportunity of recovering from his first false
step, had prevented Nabonadius from coming into actual collision with
Persia in the early part of his reign. The defeat of Croesus in the
battle of Pteria, the siege of Sardis, and its capture, followed so
rapidly on the first commencement of hostilities, that whatever his
wishes may have been, Nabonadius had it not in his power to give any
help to his rash ally. Actual war was thus avoided at this time; and
no collision having occurred, Cyrus could defer an attack on the great
kingdom of the south until he had consolidated his power in the north
and the northeast, which he rightly regarded as of the last importance.
Thus fourteen years intervened between the capture of Sardis by the
Persian arms and the commencement of the expedition against Babylon.

When at last it was rumored that the Persian king had quitted Ecbatana
(B.C. 539) and commenced his march to the south-west, Nabonadius
received the tidings with indifference. His defences were completed: his
city was amply provisioned; if the enemy should defeat him in the open
field, he might retire behind his walls, and laugh to scorn all attempts
to reduce his capital either by blockade or storm. It does not appear to
have occurred to him that it was possible to protect his territory. With
a broad, deep, and rapid river directly interposed between him and his
foe, with a network of canals spread far and wide over his country, with
an almost inexhaustible supply of human labor at his command for
the construction of such dikes, walls, or cuttings as he should deem
advisable, Nabonadius might, one would have thought, have aspired to
save his land from invasion, or have disputed inch by inch hi