TABLE OF CONTENTS. 



Pbepacb iii 



List of Iu/Ustbations viii 



The Cahotlla Basin and Desert of the CJolorado. By William Phipps Blake 1-12 



Exploration 1 



San Gorgonio Pass 1 



Geologic history 2 



Evidence of uplift 2 



Lake Cahuilla 3 



Desiccation of Lake Cahuilla 6 



Salton Sea 6 



Rate of evaporation 6 



Colorado desert 6 



Fertility of desert soils 7 



Adaptation to agriculture 7 



Geology and minerals 8 



Volcanism 9 



Mud volcanoes 9 



Salt 10 



Asphaltum and petroleum 11 



Sulphur 11 



Sodium carbonate 11 



Gold 11 



Analogous conditions elsewhere 11 



Gboqbaphical Features of the Cahuilla Basin. By Godfrey Sykes 13-20 



General description 13 



Early maps and exploration , 14 



Modern exploration " 16 



The Colorado River and its Delta 16 



The main Delta barrier 16 



The Pattie Basin barrier 17 



The Cahuilla Valley 17 



The Salton Sink 17 



The ancient shore-line 17 



The drainage from the Colorado and Delta 18 



The Whitewater drainage 18 



The Carrizo^an Felipe drainage 18 



The Chuckawalla Wash drainage 19 



Recent history 19 



Sketch of the Geolooy and Soils of the CAHinLLA Babin. By E. E. Free 21-33 



Introduction 21 



Descriptive geology 21 



Historical geology 25 



The soils 29 



Chemical Composition of the Water of Salton Sea and Its Annual Variation in Concentration 



1906-1911. By W. H. Ross 35-46 



Preliminary analysis 36 



Methods of analysis 36 



Silica 36 



Iron and aluminium 36 



Manganese 37 



Calcium and magnesium 37 



T 



