waters into
that river through the Yochow Fu canal. During the winter and spring
the water of the lake is so low that the shallow portions become
islands, separated by rivers such as the Siang and Yuen, and
numberless streams; but in summer, owing to the rise in the waters of
the Yangtsze-kiang, the whole basin of the lake is filled. It is then
about 75 m. long and 60 m. broad. About 180 m. E. of the Tung-t'ing
lake is the Poyang lake, which occupies the low-lying part of the
province of Kiang-si, and is connected with the Yangtsze by the Hu-kow
canal. The Poyang lake is also subject to a wide difference between
high and low water, but not quite to the same extent as the Tung-t'ing
lake, and its landmarks are more distinctly defined. It is about 90 m.
long by 20 broad. The T'ai lake, in the neighbourhood of Su-chow Fu,
is also celebrated for its size and the beauty of its surroundings. It
is about 150 m. in circumference, and is dotted over with islands, on
which are built temples for the devotees of religion, and
summer-houses for the votaries of pleasure from the rich and
voluptuous cities of Hang-chow and Su-chow. The boundary line between
the provinces of Cheh-kiang and Kiang-su crosses its blue waters, and
its shores are divided among thirteen prefectures. Besides these lakes
there are, among others, two in Yun-nan, the Kun-yang-hai (Tien-chi)
near Yun-nan Fu, which is 40 m. long and is connected with the
Yangtsze-kiang by the Pu-to river, and the Erh-hai (Urh-hai) to the
east of the city of Tali.

_The Great Wall._--Along the northern provinces of Chih-li, Shan-si,
Shen-si and Kan-suh, over 22 deg. of longitude (98 deg. to 120 deg. E.), stretches
the Great Wall of China, built to defend the country against foreign
aggression. It was begun in the 3rd century B.C., was repaired in the
15th century, and in the 16th century was extended by 300 m. Following
the windings the wall is 1500 m. long. Starting near the seashore[5]
at Shan-hai-kwan on the gulf of Liao-tung, where the Chinese and
Manchurian frontiers meet, it goes eastward past Peking (which is
about 35 m. to the south) and then trends S. and E. across Shan-si to
the Hwang-ho. From the neighbourhood of Peking to the Hwang-ho there
is an inner and an outer wall. The outer (northern) wall passes
through Kalgan, thus guarding the pass into Mongolia. A branch wall
separates the greater part o