38. Which kinds of stratified rocks generally have the greatest extension?
39. How do beds terminate?
40. How may planes of bedding sometimes indicate a break in the succession of strata?
41. What is the nature of joints? What are master-joints, and what is their probable cause?
42. What is cleavage, and what is its effect upon the bedding of rocks?
43. What is foliation?
44. Give examples of concretionary rocks. What is the nature of chert and flint nodules?
45. Define the terms dip and strike. What is the crop of a bed? What are anticlines and synclines?
46. What is meant by an inversion of strata?