CONTENTS. 



VOLUME T. 



CHAPTER I. 



PRELIMINARY OUTLINE. 



Subdivisions, 1. Dominant processes, 2. 



PAGE 



Astronomic Geology 2 



The earth as a planet, 2. Its satelhte, 3. Dependence 

 on the sun, 4. Meteorites, 4. 



Geognosy 5 



I. The Atmosphere 5 



Mass and extent, 6. Geologic activity, 6. A thermal 

 blanket, 7. 



II. The Hydrosphere. 7 



Oceanic dimensions, 8. Geologic activity, 8. Chief 

 horizons of activity, 9. 



III. The Lithosphere 9 



Irregularities, 10. Epicontinental seas, 11. Diversities 

 of surface, 12. The surface mantle of the lithosphere, 12. 

 The crust of the lithosphere, 13. The interior, 14. Varie- 

 ties of rock in crust, 14. Stratified rocks. 14. Conformability, 

 15. Relative ages, 15. The crystalline rocks, 16. Four 

 great sedimentary eras, 17. The Archean complex. 18. 



General Table of Geologic Divisions 19 



CHAPTER II. 



THE ATMOSPHERE AS A GEOLOGICAL AGENT. 



The Atmosphere as a Direct Agency 21 



I. Mechanical Work 21 



Transportation and deposition of dust, 22. Transporta- 

 tion and deposition of sand, 25. Formation of dunes, 26. 

 Shapes of dunes, 26. The topographic map, 30. Topography 



