160 EXERCISES ON PHYSICAL GEOLOGY. 



contained fossils. Ascertain the extent and depth of each 

 formation, the counties in which it occurs, its relation, value, 

 and importance, in an agricultural, economical, or commer- 

 cial point of view, and commit to your note-book any general 

 information relating thereto. 



4. Be careful to unite practice with theory, in the inquiries 

 above suggested, and trace every group on a geological map. 



5. Ascertain the continual progress of geological inquiry, 

 on the debateable points of drift, the glacial theory, the 

 transport by icebergs, &c. 



6. Describe the component elements of granite, gneiss, 

 and mica-schist, with their arrangement in each. 



7. What are syenite, greenstone, hornblende ? 



8. Name the characteristic features of the trap-rocks. 



9. Describe porphyry and basalt. 



10. Mention the principal volcanic products, with their 

 chemical composition. 



11. State the general characters of the igneous rocks. 



12. Explain the nature of elevating and degrading causes. 



13. Describe the composition of calcareous and arenaceous 

 deposits, and the most ready mode of distinguishing them. 



14. State the cause of drifb, and the chief instances of its 

 occurrence. 



15. Describe the structure and origin of slaty rocks. 



16. What is meant by the term alluvium, and what are 

 its distinctions ? 



17. Explain the various terms, group, formation, series, 

 system, breccia, conglomerate, dip, strike, conformable and 

 unconformable position, outlier, denudation, anticlinal and 

 synclinal axis, escarpment, valleys of dislocation, undulation, 

 denudation, and elevation, &c. 



18. Explain the difference in appearance and character of 

 a stratified and unstratified rock. 



19. State, in detail, the phenomenon of nature best adapted 

 to afford an idea of a geological formation. 



20. Copy, or otherwise impress on the recollection, the 

 diagrams comprised in the preceding chapter. 



21. Consult the works of Murchison, Conybeare, Phillips, 

 Buckland, Mantell, Bakewell, &c., which treat of physical 

 geology, and copy on tracing paper their outlines and 

 delineations. 



