RUNNING WATERS 
159 
tains, were hollowed out and rounded by the 
constant touch of running streams. In all 
countries and along all rivers the waters have 
smoothed and rubbed and polished the sharp 
points and jutting promontories ; through many 
centuries they have cut and worn away and 
modelled anew the mountains and the valleys, 
until to-day we have as a result those sweeping 
lines of beauty which mark not the Hudson 
alone, but the Seine, the Rhine, and the Dan- 
ube. 
These great carvings of the earth’s surface 
were probably never witnessed by any one gen- 
eration, or even race, of men. The work was 
wrought gradually, and yet, within the river’s 
bed, one can see evidences of erosion going on 
to-day. Water hasnot lost its cutting power. If 
it always ran straight it would work less destruc- 
tion ; but the river is very susceptible to in- 
fluences, and swings first to one side and then 
to another side, much like the pendulum of 
a clock. A current shunted over against one 
bank rebounds upon the opposite bank lower 
down ; and a violent push given to the water 
by arocky cliff may often be felt in oscillations 
for miles down the stream. It is this bound 
and rebound, from shore to shore, with its con- 
Valley 
carvings. 
Oscillations 
of the 
stream. 
