16 PRINCIPLES OF GEOLOGY. 



liquiae of organic beings which existed during the remote ages, when the 

 secondary strata were deposited beneath the ocean ; and also examined 

 the effects of convulsions within the solid substance of the eartli ; it 

 becomes necessary to turn our views to the surface.- The external 

 features of the earth afford many interesting subjects of reflection, and 

 are replete with memorials of mighty changes. Though it cannot be 

 supposed that, by investigation of its present appearance, we should be able 

 to determine completely its former condition, enough is known to assure 

 us that after the earth was dried and made habitable, its whole surface 

 was again submerged and overwhelmed by an irresistible flood. Of many 

 important facts which come under the consideration of geologists, the 

 " Deluge" is, perhaps, the most remarkable ; and it is established by such 

 clear and positive arguments, that if any one point of natural history 

 may be considered as proved, the deluge must be admitted to have hap- 

 pened, because it has left full evidence in plain and characteristic effects 

 upon the surface of the earth. 



Formerly, indeed, when geology was in its infancy, a wrong method 

 was followed, and the fossil shells and other organic remains, which 

 were certainly deposited in the rocks before the deluge, were ap- 

 pealed to as evidence of that event. This mistake was natural enough 

 in that early period of the science, but at present cannot be maintained, 

 without a gross anachronism. Examine where we may the action of 

 moving water, whether in little mountain rills, lakes ruffled by the wind, 

 flowing rivers, or on the margin of the sea, we every where perceive the 

 same effects ; stones smoothed and rounded, masses crumbled and dis- 

 integrated. We may trace the old channels of rivers by the pebbles 

 left in them, and the set of the tide by their accumulation on the shore ; 

 in a word, the action of moving water is known by its effects. As the 

 old channel of a rapid stream is filled with pebbles that declare the force 

 of the current, so the whole earth is covered by pebbles, the wreck of 

 a general flood. Filling the vallies, overspreading the plains, and cover- 

 ing the hills, rounded stones, of all sizes and all kinds, mixed together in 

 as much confusion as pebbles on the sea-shore, (fragments of all the 



