ory for the known world of each period. Such an
intense, concentrated national life as occurred in those little
Mediterranean countries in ancient times is not duplicated now, unless
we find a parallel in Japan's recent career in the Yellow Sea basin.
There was something as cosmic in the colonial ventures of the Greeks to
the wind-swept shores of the Crimea or barbarous wilds of Massilia, as
in the establishment of English settlements on the brimming rivers of
Virginia or the torrid coast of Malacca. Alexander's conquest of the
Asiatic rim of the Mediterranean and Rome's political unification of the
basin had a significance for ancient times comparable with the
Russification of northern Asia and the establishment of the British
Empire for our day.

The ocean has always performed one function in the evolution of history;
it has provided the outlet for the exercise of redundant national
powers. The abundance of opportunity which it presents to these
disengaged energies depends upon the size, location and other geographic
conditions of the bordering lands. These opportunities are limited in an
enclosed basin, larger in the oceans, and largest in the northern halves
of the oceans, owing to the widening of all land-masses towards the
north and the consequent contraction of the oceans and seas in the same
latitudes.

[Sidenote: Contrasted historical roles of northern and southern
hemispheres.]

A result of this grouping is the abundance of land in the northern
hemisphere, and the vast predominance of water in the southern, by
reason of which these two hemispheres have each assumed a distinct role
in history. The northern hemisphere offers the largest advantages for
the habitation of man, and significantly enough, contains a population
five times that of the southern hemisphere. The latter, on the other
hand, with its vast, unbroken water areas, has been the great oceanic
highway for circum-mundane exploration and trade. This great water
girdle of the South Seas had to be discovered before the spherical form
of the earth could be proven. In the wide territory of the northern
hemisphere civilization has experienced an uninterrupted development,
first in the Old World, because this offered in its large area north of
the equator the fundamental conditions for rapid evolution; then it was
transplanted with greatest success to North America. The northern
hemisphere contains, therefore, "the zone of greatest historical
density,"