278 DENUDATION, OR GENERAL EROSION. 



But even this gives us no adequate conception of the time involved 

 in the geological history of the earth. For rocks disintegrated into 

 soils, and deposited as sediments, are again reconsolidated into rocks, 

 lifted into land- surfaces, to be again disintegrated into soils, transported 

 and deposited as sediments. And thus the same materials have been 

 worked over and over again, perhaps many times. Thus the history of 

 the earth, recorded in stratified rocks, stretches out in apparently end- 

 less vista. And still beyond this, beyond the recorded history, is the 

 infinite unknown abyss of the unrecorded. The domain of Geology is 

 nothing less than (to us) inconceivable or infinite time. 



