CONTENTS 



CHAPTER I 

 THE COMPILATION OF EARTH HISTORY 



PAGB 



The sources of the history Subdivisions of geology The study of earth 

 features and their significance Tabular recapitulation Geological 

 processes not universal Change, and not stability, the order of nature 



Observational geology versus speculative philosophy The scientific 

 attitude and temper The value of the hypothesis Reading refer- 

 ences ............. 1 



CHAPTER II 

 THE FIGURE OF THE EARTH 



The lithosphere and its envelopes The evolution of ideas concerning the 

 earth's figure The oblateness of the earth The arrangement of 

 oceans and continents The figure toward which the earth is tending 



Astronomical versus geodetic observations Changes of figure dur- 

 ing contraction of a spherical body The earlier figures of the earth 



The continents and oceans at the close of the Paleozoic era The 

 flooded portions of the present continents The floors of the hydro- 

 sphere and atmosphere Reading references 8 



CHAPTER III 

 THE NATURE OF THE MATERIALS IN THE LITHOSPHERE 



The rigid quality of our planet Probable composition of the earth's core 



The earth a magnet The chemical constitution of the earth's sur- 

 face shell The essential nature of crystals The lithosphere a com- 

 plex of interlocking crystals Some properties of natural crystals, 

 minerals The alterations of minerals Reading references . . 20 



CHAPTER IV 

 THE ROCKS OF THE EARTH'S SURFACE SHELL 



The processes by which rocks are formed The marks of origin The 

 metamorphic rocks Characteristic textures of the igneous rocks 

 The classification of rocks Subdivisions of the sedimentary rocks 



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