1 68 The Founders of Geology LECT. 



history of our globe must be explained by what can be 

 seen to be happening now, or to have happened only 

 recently. The dominant idea in his philosophy is that 

 the present is the key to the past. We have grown so 

 familiar with this idea, it enters so intimately into all our 

 conceptions in regard to geological questions, that we do 

 not readily realize the genius of the man who first grasped 

 it with unerring insight, and made it the chief corner-stone 

 of modern geology. 



From the time of his youthful rambles in Norfolk, 

 Hutton had been struck with the universal proofs that 

 the surface of the earth has not always been as it is 

 to-day. Everywhere below the covering of soil he found 

 evidence of former conditions, entirely unlike those 

 visible now. In the great majority of cases, he noticed 

 that the rocks there to be seen consist of strata, disposed 

 in orderly arrangement parallel with each other. Some 

 of these strata are formed of pudding-stone, others of sand- 

 stone, of shale, of limestone, and so forth, differing in 

 many respects from each other, but agreeing in one essential 

 character, that they are composed of fragmentary or detrital 

 material, derived from rocks older than themselves. He 

 saw that these various strata could be exactly paralleled 

 among the accumulations now taking place under the sea. 

 The pudding-stones were in his eyes only compacted 

 gravels, the sandstones, were indurated sand, the lime- 

 stones were in great part derived from the accumulation 

 of the remains of marine calcareous organisms, the shales 

 from the consolidation of mud and silt. The wide extent 

 of these strata, forming, as they do, most of the dry land, 

 seemed to him to point to the sea as the only large 



