Farthest to the east was ancient China, drained by two great rivers, the
Hoang and the Yangtze. Its remote situation and the barriers on the west
formed by the spurs of the Himalayas, combined to make this land the
most isolated of the civilized lands of the Old World.
To the west of China lies India, also drained by two great rivers, the
Indus and the Ganges, which rise among the slopes of the Himalayas and
flow in different directions to the sea. These two countries--China and
India--stood nearly alone in ancient times, separated from the peoples
of western Asia by the wide, dry plateau of Iran, and hence these
countries did not exercise a great influence upon the ancient world, or
come into historical view until much later.
[Illustration: THE KNOWN WORLD--ABOUT B.C. 450.]
[Illustration: ABOUT B.C. 325]
[Illustration: ABOUT A.D. 300]