ii 



CONTENTS. 



on the Animal and Vegetable Kingdom.—Height of Mount- 

 ains. — Highest Land in Asia— -In Europe — In America.— 

 Shape of Hills and Mountains .... Page 50 



CHAPTER V. 



ELEMENTARY FACTS AND PRINCIPLES OF GEOLOGY. 



Our Knowledge of the Internal Structure of the Earth very 

 limited. — Variety of Minerals and Rocks, arranged in a de- 

 terminate Order. — Advantages of Geological Knowledge. — 

 Division of Rocks: Stratified, Unstratified, Parallel, In- 

 clined, Cropping out, Dip, Thickness, Outliers, Escarpment, 

 Faults, Mineral Veins, Rock Dike, Clay Dike, Formations. — 

 Illustrations. — How to Observe. — Valleys of Denudation, 

 &c 57 



CHAPTER VI. 



. CLASSIFICATION OF ROCKS. 



Classification : Primary, Secondary, Transition, Tertiary.— 

 Classification of Conybeare and Philips.— Of De la Beche. — 

 Primitive Rocks described. — Mr. Lyell's Views. — Hypogene. 

 — Division of Primary Rocks : Granite, Syenite, Felspathic 

 &c. — Professor Hitchcock's Account of Granite. — Gneiss.— 

 Mica Slate. — Hornblende Rock. — Crystalline Limestone. — 

 Quartz Rock 67 



CHAPTER VII. 



TRANSITION AND SECONDARY ROCKS. 



Transition Rocks.— How divided.— Slate.— Hornstone. — Whet- 

 stones. — Hones. — How Slate is Formed. — Its Cleavage.— 

 Transition Limestone. — Graywacke.— Old Red Sandstone. — 

 Claystone 80 



CHAPTER VHL 



SECONDARY ROCKS. 



Carboniferous Group, 

 Division of Secondary Rocks. — Coal Measures. — Vegetation ol 

 Carboniferous Formation. — Lower Secondary Rocks, how 

 divided. — Millstone Grit— Its Mineral Contents.— Carbonif- 

 erous Limestone— Its Extent in this Country.— Section of 

 Coal Measures in England. — South Gloucestershire Coal- 

 basin. — Coal-fields of Derbyshire. — Coalbrook Dale. — Coal 

 Measures of North America . . . . . . 85 



