138 ELEMENTARY GEOLOGY 
accumulation of sediment that is forming in its bed. 
Along many coasts situated near dry lands, the off- 
shore winds are directly contributing sediment to the 
sea. Indeed, everywhere, this source of sediment from 
the land is one of the ways in which ocean deposits are 
being derived. 
ACTION OF THE WIND 
EROSION. 
DEPOSITION. 
On MOUNTAINS. 
Violent mountain winds 
remove all small particles. 
Winds remoye, but are 
too violent for deposit. 
On Moist 
LANDS. 
Forest and other plant 
protection prevents ero- 
sion. 
Deposit possible only 
in rare places, where for 
some reason plant protec- 
tion is absent, and a sup- 
ply of sand near by. 
In Artp LANDs. 
Constant movement of 
soil. Cliffs and exposed 
rocks, chipped and cut. 
Rocks stripped of soil 
and kept bare. 
Formation of sand beds; 
of sand dunes; of loess. 
Material furnished to the 
sea. 
ON THE SEA- 
COAST. 
Wave-formed sand, 
ground finer by friction 
when moved by wind. 
Lifted by the air, and 
hence exposed to weather 
and plant action. Sand- 
blast action also present. 
Sand dunes formed. In 
codperation with waves, 
islands built. Beaches 
raised higher. Materials 
mainly taken from the sea 
and added to the land; 
but the reverse action 
sometimes present. 
