ick at the bottom and 16
at the top. Towers stand at certain intervals, and there are gates here
and there. It is constructed of stone, brick, and earth. It is in parts
much ruined, especially in the west, and in some places only heaps of
earth are left.

Why was this immense wall erected? The Chinese are a peaceful people,
and they surrounded themselves with walls to prevent intrusion from
outside. In China there are 1553 towns enclosed in massive stone walls,
and the great emperor in the third century B.C. naturally
thought of building a wall in the same way all round his extensive
kingdom. It was principally from the north that danger threatened. There
lived the nomads of Eastern Turkestan and Mongolia, savage, brave, and
warlike horsemen. To them the Chinese wall was an insurmountable
obstacle. But precisely on that account this wall has also affected the
destiny of Europe, for the wild mounted hordes, finding the way
southwards to China barred, advanced westwards instead, and in the
fourth century, in conjunction with the Alans, overran extensive areas
of Europe.

The Great Wall, however, could not protect China for ever. In the year
1280 the country was conquered by Jenghis Khan's grandson, Kublai Khan,
Marco Polo's friend and patron. He, too, was a great builder. He
constructed the Grand Canal (see map, p. 174) between Peking and
Hang-chau, immediately to the south-west of Shanghai. His idea was that
the rice harvest of the southern provinces should also benefit the
northern parts of the country. Previously the rice had been freighted on
junks and carried along the coast, where it was exposed to the attacks
of Japanese pirates. Now the junks could pass safely through the country
by the new canal. The imperial canal is 840 miles long, crosses the
Yellow and Blue rivers, and is still in use. It is a memorial of the
hundred years' rule of the Mongols.

In 1644 China was conquered by the Manchu dynasty, which still reigns.
Exactly a hundred years earlier the Portuguese had seized Macao, not far
from Hong Kong. Since then, and particularly during recent decades,
Europeans have encroached on Chinese soil. The French possessions on the
peninsula of Further India were formerly under Chinese protection. The
Great Powers have made themselves masters of some of the best harbours
in China. On two occasions, the latter during the Boxer insurrection in
1900, Peking has been entered by the combined troops of European
nation