4 CONTENTS. 
Geographic and geologic details of highlands — Continued. Page. 
Artillery Mountains 22 
Location 22 
Topographic features 22 
Rock masses 22 
White Hills 23 
Location 23 
Topographic features 23 
Rock masses 23 
Cerbat Mountains 23 
Location 23 
Topographic features 23 
Rock masses 23 
Structure 24 
Hualpai Mountains 24 
Location 24 
Topographic features 24 
Rock masses 25 
Structure ■ 25 
Aubrey Hills 25 
Location 25 
Topographic features 25 
Rock masses 25 
Black Mountains 25 
Location 25 
Topographic features 25 
Rock masses 26 
Black Mesa 26 
Location 26 
Topographic features 26 
Rock masses 27 
Mohave Mountains 27 
Location • 27 
Topographic features 27 
Rock masses 28 
Harcuvar and Harquahala Mountains 28 
Location 28 
Topographic features 28 
Rock masses 28 
Buckskin Mountains 28 
Location : 28 
Topographic features 28 
Rock masses 29 
Palomas and Dome Rock ranges 29 
Geographic and geologic details of valleys 29 
Colorado Valley 29 
General statement 29 
Mouth of Grand Canyon 30 
Grand Wash Trough 30 
Haulpai Wash 33 
Virgin Canyon 34 
Temple Bar 35 
" Virgin Valley 36 
Boulder Canyon ' 36 
