ghways history repeats itself. The maritime plain of
Palestine has been an established route of commerce and war from the
time of Sennacherib to Napoleon.[1] The Danube Valley has admitted to
central Europe a long list of barbarian invaders, covering the period
from Attila the Hun to the Turkish besiegers of Vienna in 1683. The
history of the Danube Valley has been one of warring throngs, of
shifting political frontiers, and unassimilated races; but as the river
is a great natural highway, every neighboring state wants to front upon
it and strives to secure it as a boundary.

The movements of peoples constantly recur to these old grooves. The
unmarked path of the voyageur's canoe, bringing out pelts from Lake
Superior to the fur market at Montreal, is followed to-day by whaleback
steamers with their cargoes of Manitoba wheat. To-day the Mohawk
depression through the northern Appalachians diverts some of Canada's
trade from the Great Lakes to the Hudson, just as in the seventeenth
century it enabled the Dutch at New Amsterdam and later the English at
Albany to tap the fur trade of Canada's frozen forests. Formerly a line
of stream and portage, it carries now the Erie Canal and New York
Central Railroad.[2] Similarly the narrow level belt of land extending
from the mouth of the Hudson to the eastern elbow of the lower Delaware,
defining the outer margin of the rough hill country of northern New
Jersey and the inner margin of the smooth coastal plain, has been from
savage days such a natural thoroughfare. Here ran the trail of the
Lenni-Lenapi Indians; a little later, the old Dutch road between New
Amsterdam and the Delaware trading-posts; yet later the King's Highway
from New York to Philadelphia. In 1838 it became the route of the
Delaware and Raritan Canal, and more recently of the Pennsylvania
Railroad between New York and Philadelphia.[3]

The early Aryans, in their gradual dispersion over northwestern India,
reached the Arabian Sea chiefly by a route running southward from the
Indus-Ganges divide, between the eastern border of the Rajputana Desert
and the western foot of the Aravalli Hills. The streams flowing down
from this range across the thirsty plains unite to form the Luni River,
which draws a dead-line to the advance of the desert. Here a smooth and
well-watered path brought the early Aryans of India to a fertile coast
along the Gulf of Cambay.[4] In the palmy days of the Mongol Empire
during the seventeenth