CHAPTER VII 
WIND EROSION 
Use of the Word Erosion. — By the word erosion, as 
used here, is meant the wearing down of the land by 
agents which are able to remove substances. The agents 
that can do this are air, water (rain, river, lake, and 
ocean), and ice. The most important mode of erosive 
action is that of corrasion, which is mechanical. How- 
ever, hand in hand with this, goes the chemical work 
of corrosion. No attempt is made to separate these, for 
they are most intimately related. Since materials are 
removed by erosion and deposited by the same agencies, 
these processes of destruction and construction are 
considered together. 
Mode of Wind Action. — The wind is an impor- 
tant agent in geological change. It ruffles the surface 
of lakes and oceans, producing waves and currents 
which bring about numerous changes. It aids in the 
distribution of seeds, so that many plants readily find 
it possible to spread themselves widely over the land. 
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