he slowness of the ancient Egyptians to take the short step
forward from river to marine navigation can undoubtedly be traced to the
fact that the sour swamps, barren sand-dunes, and pestilential marshes
on the seaward side of the Nile delta must have always been sparsely
populated as they are to-day,[466] and that a broad stretch of sandy waste
formed their Red Sea littoral.

On the other hand, where the hem of the continents is fertile enough to
support a dense population, a large number of people are brought into
contact with the sea, even where no elaborate articulation lengthens the
shoreline. When this teeming humanity of a garden littoral is barred
from landward expansion by desert or mountain, or by the already
overcrowded population of its own hinterland, it wells over the brim of
its home country, no matter how large, and overflows to other lands
across the seas. The congested population of the fertile and indented
coast of southern China, though not strictly speaking a sea-faring
people, found an outlet for their redundant humanity and their commerce
in the tropical Sunda Islands. By the sixth century their trading junks
were doing an active business in the harbors of Java, Sumatra, and
Malacca; they had even reached Ceylon and the Persian Gulf, and a little
later were visiting the great focal market of Aden at the entrance of
the Red Sea.[467] A strong infusion of Chinese blood improved the Malay
stock in the Sunda Islands, and later in North Borneo and certain of the
Philippines, whither their traders and emigrants turned in the
fourteenth century, when they found their opportunities curtailed in the
archipelago to the south by the spread of Islam.[468] Now the "yellow
peril" threatens the whole circle of these islands from Luzon to
Sumatra.

Similarly India, first from its eastern, later from its western coast,
sent a stream of traders, Buddhist priests, and colonists to the Sunda
Islands, and especially to Java, as early as the fifth century of our
era, whence Indian civilization, religion, and elements of the Sanskrit
tongue spread to Borneo, Sumatra, Bali, Lombok, and even to some
smaller islands among the Molucca group.[469] The Hindus became the
dominant commercial nation of the Indian Ocean long before the great
development of Arabian sea power, and later shared the trade of the East
African coast with the merchants of Oman and Yemen.[470] To-day they form
a considerable mercantile class in the port