tasius resolved to found a new colony,
so strong, that it should defy the power of the Persian, so far advanced
towards Assyria, that its stationary troops might defend the province by
the menace or operation of offensive war. For this purpose, the town
of Dara, fourteen miles from Nisibis, and four days' journey from the
Tigris, was peopled and adorned; the hasty works of Anastasius were
improved by the perseverance of Justinian; and, without insisting on
places less important, the fortifications of Dara may represent the
military architecture of the age. The city was surrounded with two
walls, and the interval between them, of fifty paces, afforded a retreat
to the cattle of the besieged. The inner wall was a monument of strength
and beauty: it measured sixty feet from the ground, and the height of
the towers was one hundred feet; the loopholes, from whence an enemy
might be annoyed with missile weapons, were small, but numerous; the
soldiers were planted along the rampart, under the shelter of double
galleries, and a third platform, spacious and secure, was raised on the
summit of the towers. The exterior wall appears to have been less lofty,
but more solid; and each tower was protected by a quadrangular bulwark.
A hard, rocky soil resisted the tools of the miners, and on the
south-east, where the ground was more tractable, their approach was
retarded by a new work, which advanced in the shape of a half-moon. The
double and treble ditches were filled with a stream of water; and in the
management of the river, the most skilful labor was employed to supply
the inhabitants, to distress the besiegers, and to prevent the mischiefs
of a natural or artificial inundation. Dara continued more than sixty
years to fulfil the wishes of its founders, and to provoke the jealousy
of the Persians, who incessantly complained, that this impregnable
fortress had been constructed in manifest violation of the treaty of
peace between the two empires.

Between the Euxine and the Caspian, the countries of Colchos, Iberia,
and Albania, are intersected in every direction by the branches of Mount
Caucasus; and the two principal _gates_, or passes, from north to south,
have been frequently confounded in the geography both of the ancients
and moderns. The name of _Caspian_ or _Albanian_ gates is properly
applied to Derbend, which occupies a short declivity between the
mountains and the sea: the city, if we give credit to local tradition,
had bee