CONTENTS. 
Page. 
Introduction , 13 
Field work and acknowledgments 13 
Location and area 14 
Literature - 15 
The Great Basin 16 
Topography 1 16 
Climate 17 
Hydrology 18 
General statement . 18 
Streams 18 
Springs 19 
Hot or warm springs 19 
Cold springs 20 
Tanks 21. 
Wells 21 
Snow 22 
Signs of water : 22 
Animal life 23 
Vegetation : 2."> 
Culture 21 
Industries 24 
Towns 25 
Railroads and stages 26 
Roads and trails 26 
Stratigraphic geology 26 
Pre-Cambrian 26 
Cambrian 28 
Ordovician and Silurian 28 
Devonian 29 
Carboniferous 30 
Post-Jurassic and pre-Tertiary igneous rocks 30 
Tertiary 31 
Pleistocene and Recent 35 
Travertine 35 
Desert gravels : 35 
Playa deposits : 
Sand dunes 36 
Definitions of igneous rocks 37 
Geologic history__„____„_, ___. 
3 
