150 ELEMENTARY GEOLOGY 
ACTION OF UNDERGROUND WATER 
MovEMENT. 
RESULTS ACCOMPLISHED. 
Sinks into the earth. 
Dissolves and changes minerals. 
Weakens rocks. Carves channel- 
ways. 
Rises in hot springs. 
Brings mineral substances to the 
surface in mineral springs. 
Rises in springs. 
Brings mineral matter to the 
surface.1 Furnishes water supply. 
Follows subterranean channel- 
ways in limestone. 
Carves caverns. Deposits sta- 
lactites and stalagmites. Reaches 
the surface in the form of springs. 
- Passes between impervious lay- 
ers in a porous stratum. 
This condition gives rise to the 
important artesian wells. 
1 This is true of all underground water which reaches the surface. 
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