FOR 



GENEEAL EEADEES, 



THE CRUST WE DWELL UPOK 



NATURE OF THE EARTH'S CRUST OR SOLID EXTERIOR DIFFERS FROM 

 THE INTERIOR COMPOSED OF ROCKS AND ROCK-FORMATIONS 

 THESE THE THEMES OF GEOLOGICAL INVESTIGATION TECHNICAL 

 MEANING OF THE TEJIM "ROCK" STRATIFIED AND UNSTRATIFIED 



ROCKS HOW AND BY WHAT PROCESSES FORMED OLDER AND 



YOUNGER ROCKS EXAMPLES OF HOW DISTINGUISHED CHRONO- 

 LOGICAL ARRANGEMENT OF ROCK-FORMATIONS EACH A CHAPTER 

 OF WORLD -HISTORY ATTRACTIVE NATURE OF THIS HISTORY 

 FACTS ARRIVED AT BY A STUDY OF THE EARTH'S CRUST THEIR 

 THEORETICAL AND PRACTICAL IMPORTANCE. 



WHEREVER we travel we find the land made up of rocks 

 and rocky substances. If we go to the sea-shores, we find 

 similar substances stretching away beneath the waters, or 

 rising up in mid-ocean as reefs and islands. The fair in- 

 ference therefore is, that all the exterior of our planet is 

 composed of rocks and rock-formations, and that the ocean 

 merely occupies the great hollows or depressions in the 

 same way as the lesser lakes and tarns occupy the rock- 



B 



