mber of springs in the country. They are often found
on the flat-topped hills which dot the Karroo. Besides the ordinary
springs, mineral and thermal springs are found in several places.

_Lakes and Caves._--Cape Colony does not possess any lakes properly so
called. There are, however, numerous natural basins which, filled after
heavy rain, rapidly dry up, leaving an incrustation of salt on the
ground, whence their name of salt pans. The largest, Commissioner's Salt
Pan, in the arid north-west district, is 18 to 20 m. in circumference.
Besides these pans there are in the interior plateaus many shallow pools
or _vleis_ whose extent varies according to the dryness or moisture of
the climate. West of Knysna, and separated from the seashore by a
sandbank only, are a series of five _vleis_, turned in flood times into
one sheet of water and sending occasional spills to the ocean. These
_vleis_ are known collectively as "the lakes." In the Zwarteberg of the
central chain are the Cango Caves, a remarkable series of caverns
containing many thousand of stalactites and stalagmites. These caves,
distant 20 m. from Oudtshoorn, have been formed in a dolomite limestone
bed about 800 ft. thick. There are over 120 separate chambers, the
caverns extending nearly a mile in a straight line.

_Climate_.--The climate of Cape Colony is noted for its healthiness. Its
chief characteristics are the dryness and clearness of the atmosphere
and the considerable daily range in temperature; whilst nevertheless the
extremes of heat and cold are rarely encountered. The mean annual
temperature over the greater part of the country is under 65 deg. F. The
chief agents in determining the climate are the vast masses of water in
the southern hemisphere and the elevation of the land. The large extent
of ocean is primarily responsible for the lower temperature of the air
in places south of the tropics compared with that experienced in
countries in the same latitude north of the equator. Thus Cape Town,
about 34 deg. S., has a mean temperature, 63 deg. F., which corresponds
with that of the French and Italian Riviera, in 41 deg. to 43 deg. N.
For the dryness of the atmosphere the elevation of the country is
responsible. The east and south-east winds, which contain most moisture,
dissipate their strength against the Drakensberg and other mountain
ranges which guard the interior. Thus while the coast-lands, especially
in the south-east, enjoy an ample rainfall, t