ast, however, where the
formidable rampart of the Zagros forbade all progress, no such extension
took place. Those lofty and precipitous chains which we now call the
mountains of Kurdistan, were only to be crossed in two or three places, and
by passes which during their few months of freedom from snow and floods
gave access to the high-lying plains of Media. These narrow defiles might
well be traversed by an army in a summer campaign, but neither dwellings
nor cultivated lands could invade such a district with success; at most
they could take possession of the few spots of fertile soil which lay at
the mouth of the lateral valleys; such, for example, was the plain of
Arbeles which was watered by the great Zab before its junction with the
Tigris. Towards the south there was no natural barrier, but in that
direction all development was hindered by the density of the Chaldee
population which was thickly spread over the country above Babylon and
about the numerous towns and villages which looked towards that city as
their capital. To the north, on the other hand, the wide terraces which
mounted like steps from the plains of Mesopotamia to the mountains of
Armenia offered an ample field for expansion. To the west there was still
more room. Little by little rural and urban life overflowed the valley of
the Tigris into that of the Chaboras or Khabour, the principal affluent of
the Euphrates, until at last it reached the banks of the great western
river itself. In all Northern Mesopotamia, between the hills of the Sinjar
and the last slopes of Mount Masius, the Assyrians encountered only nomad
tribes whom they could drive when they chose into the Syrian desert. Over
all that region the remains of artificial mounds have been found which must
at one time have been the sites of palaces and cities. In some cases the
gullies cut in their flanks by the rain discover broken walls and fragments
of sculpture whose style is that of the Ninevitish monuments.[14]

In the course of their victorious career the Assyrians annexed several
other states, such as Syria and Chaldaea, Cappadocia and Armenia, but those
countries were never more than external dependencies, than conquered
provinces. Taking Assyria proper at its greatest development, we may say
that it comprised Northern Mesopotamia and the territories which faced it
from the other bank of the Tigris and lay between the stream and the lower
slopes of the mountains. The heart of the countr