QUESTIONS. 347 



277. What is the name of the highest of these cones, and what is 

 said of it ? How were basins, so called, formed in the Tertiary pe- 

 riod ? What is the arrangement of the London basin ? 



278. How do artesian wells operate in such basins? What is said 

 of Tertiary continent-making? What proportion of the land was 

 brought above the surface of the water in this period ? What addi- 

 tions were made to North America ? What is said of the condition 

 of this continent at the end of this period ? 



279. What is the Post-tertiary period? What was to be done in it 

 to the continents ? Into what three epochs is it divided ? What was 

 done in the first ? What in the second ? 



280. What in the third ? Indicate the extent of the reign of ice in 

 the Glacial epoch. What is supposed to have been the cause of the 

 cold ? What is said of the glaciers of this period ? 



281. What is drift? What modified drift? What are the two 

 theories about drift ? What is the truth in regard to them ? What 

 changes were produced by the drift ? What change in the Niagara 

 River ? What is said of the heights at which drift is found ? 



282. What is said of the shape and size of boulders ? What of the 

 distances to which they have been carried? What examples are 

 given of the transportation of them across deep valleys ? What is 

 stated about the distribution of boulders ? 



283. What is said of glacial markings ? What of the rockes mon- 

 tonnets f What of the work done by icebergs, and that done by gla- 

 ciers ? What of the localities of the glacial markings ? 



284. What general .change in the land occurred in the Champlain 

 epoch ? What resulted from this change ? What is the character of 

 the formations of this epoch ? How are boulders situated in relation 

 to these formations ? What is said of the elevated heights to which 

 these formations sometimes reached ? What is said of the wide dis- 

 persion of the smaller materials of the drift ? 



285. What are the river-plains and sea -beaches of the Cham- 

 plain epoch now ? What is said of the subsidence of land in this 

 epoch ? What of the movement in the Terrace epoch ? What effect 

 was produced by this on the Champlain strata? To what is the 

 term terraces applied ? What is said of the arrangement of ter- 

 races ? 



286. Describe what is represented in Figs. 168 and 169. State in 

 the general how terraces were formed. 



287. Explain by Figs. 170 and 171 the manner in which they were 

 commonly made. 



288. What is said of sea-beaches ? Describe in full the changes 

 that occurred in the Niagara River in the Post-tertiary period. 



289. What calculations have been made about the rime occupied 



