Vlil PREFACE. 



above all it must be delivered from that materialistic 

 infidelity, which, by robbing nature of the spiritual 

 element, and of its presiding Divinity, makes science 

 dry, barren, and repulsive, diminishes its educational 

 value, and even renders it less efficient for purposes 

 of practical research. 



That the want of these preliminary conditions mars 

 much of the popular science of our day is too evident ; 

 and I confess that the wish to attempt something 

 better, and thereby to revive the interest in geological 

 study, to attract attention to its educational value, and 

 to remove the misapprehensions which exist in some 

 quarters respecting it, were principal reasons which 

 induced me to undertake the series of papers for the 

 Leisure Hour, which are reproduced, with some amend- 

 mer.ts and extension, in the present work. How far 

 I have succeeded, I must leave to the intelligent and, 

 I trust, indulgent reader to decide. In any case I 

 have presented this many-sided subject in the aspect 

 in which it appears to a geologist whose studies have 

 led him to compare with each other the two great 

 continental areas which are the classic ground of the 

 science, and who retains his faith in those unseen 

 realities of which the history of the earth itself is but 

 one of the shadows projected on the field of time. 



To geologists who may glance at the following 



