principal one was Massilia, or Marseilles. Through the traders of this
city the ancient world obtained a supply of tin from Britain, a country
which is now called England.

GREEK COLONIES AS CENTERS OF CIVILIZATION. The Greeks in these
colonies traded with the natives whose villages were near by, and many
of the natives learned to live like the Greeks. In this way the Greeks
became teachers of civilization, and the Greek world, which at first was
made up of cities on the shores of the Aegean Sea, was spread from place
to place along the coasts of the Mediterranean Sea.

[Illustration: A GREEK TRIREME]

GREEK SHIPS. The ships of the Greeks were very different from
modern vessels. Of course they were not driven by steam, nor did they
rely as much on sails as modern sailing ships do. They had sails, but
were driven forward mostly by their oars. The trireme, or ordinary
war-ship, had its oars arranged in three banks, fifty men rowing at
once. After these had rowed several hours, or a "watch," another fifty
took their places, and finally a third fifty, so that the ships could be
rowed at high speed all the time. With the aid of its two sails a
trireme is said to have gone one hundred and fifty miles in a day and a
night. These boats were about one hundred and twenty feet long and
fifteen feet wide. They could be rowed in shallow water, but were not
high enough to ride heavy seas safely. They had a sharp beak, which,
driven against an enemy's ship, would break in its sides. The Greek
grain ships and freight boats were heavier and more capable of enduring
rough weather.

[Illustration: ALEXANDER THE GREAT After the bust in the