A river always takes the easiest course through channels and soft
ground to the sea, flowing swiftly down mountain sides but much more slowly on
the level plains.
On the plain the river takes advantage of every difference in
gradient. this winding course is accentuated by the process of silting and
erosion. As river flows round a curve, the water on the outer bend moves more
swiftly to cover the greater distance in the same time as the water flowing
past the inner bend.
The more rapidly moving water will tend to wear away the banks of
the channel, while the slower movement of the water on the inside wall will
allow silting to take place. When the curve becomes more pronounced it is known
as a "meander". Notable examples of meanders are to be found in the
Wye in England, and the Meuse in France.
Sometimes the river erodes the bank so fiercely that a new channel
is formed, leaving an island of earth in the middle of the stream.
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