f the organized government of man is largely the record of the
improvement of communications. Side by side with the unending struggle
of human reason against cold and hunger and disease we can watch the
contest against distance, against ocean and mountain and desert, against
storms and seasons. There can be few subjects more fascinating for a
historian to study than the record of the migrations of the tribes of
men. He might begin, if he wished, with the migrations of animals and
describe the westward progress of the many species whose course can be
traced by experts along the natural highways of Western Europe. Some of
them, so the books tell us, reached the end of their journey while
Britain was still joined to the continent. Others arrived too late and
were cut off by the straits of Dover. I like to form an imaginary
picture, which the austerity of the scientific conscience will, I know,
repudiate with horror, of the unhappy congregation, mournfully assembled
bag and baggage on the edge of the straits and gazing wistfully across
at the white cliffs of England, which they were not privileged to
reach--_tendentesque manus ripae ulterioris amore_, 'stretching out
their paws in longing for the further bank.'

Our historian would then go on to describe the early 'wanderings of
peoples' (_Voelkerwanderungen_) how whole tribes would move off in the
spring-time in the search for fresh hunting-grounds or pasture. He would
trace the course of that westward push which, starting from somewhere in
Asia, brought its impact to bear on the northern provinces of the Roman
Empire and eventually loosened its whole fabric. He would show how
Europe, as we know it, was welded into unity by the attacks of
migratory warriors on three flanks--the Huns and the Tartars, a host of
horsemen riding light over the steppes of Russia and Hungary: the Arabs,
bearing Islam with them on their camels as they moved westward along
North Africa and then pushing across into Spain: and the Northmen of
Scandinavia, those carvers of kingdoms and earliest conquerors of the
open sea, who left their mark on England and northern France, on Sicily
and southern Italy, on the Balkan Peninsula, on Russia, on Greenland,
and as far as North America. Then, passing to Africa and Asia, he would
describe the life of the pack-saddle and the caravan, the long and
mysterious inland routes from the Mediterranean to Nubia and Nigeria, or
from Damascus with the pilgrims to Medina,