66 W J MCGEE UNIFORMITARIANISM AND DEFORMATION. 



predominantly deductive and involutionary, and knowledge expanded 

 on a relatively low plane, increasing in quantity rather than improving 

 in quality. It may be called the stage of speculation. 



THE STAGE OF RATIOCINATION. 



The geologist of the second generation, like his predecessors, began 

 with observation, proceeded to discrimination, and gradually rose to 

 homologic reasoning, and reaching this plane he was able to group facts 

 and eliminate crude hypotheses, so that the ratio of hypothesis to fact 

 diminished. Concurrently the field of geology widened, and the geologist 

 found matter of interest not simply in deep mines and distant mountains, 

 but in the undisturbed strata nearer at hand, and even the superficial 

 deposits and the products of decomposition of rocks, and eventually the 

 land forms into which the strata and residua are sculptured, received 

 attention!. So during this stage the progress of knowledge concerning 

 the earth was from the indefinite to the definite, from the vague to the 

 trenchant, from lax speculation toward exact reasoning, from hypothesis 

 to theory ; yet there was a heritage of crude hypothesis (of which a part 

 persists) by which progress was hindered. 



Such was the second stage in the progress in knowledge concerning 

 the earthcrust. During this stage many fruitless hj^potheses were elim- 

 inated, many fruitful theories formulated. The attendant intellectual 

 processes were largely inductive and involutionary, and knowledge rose 

 to a higher plane, improving in quality as it grew in quantit}^ It may 

 be called the stage of theory. 



THE STAGE OF GENETIC CLASSIFICATION. 



The third stage in the development of geology was initiated when 

 Lyell and his disciples perceived that the river carves its own valley, 

 that rain and rills sculpture the hillside, and that oceans, bays and lakes 

 line their own bottoms with stratified deposits homologous with rock 

 formations. One of the first fruits, of this extension of knowledge was 

 increased interest in the commonplace and simple; the geologist found 

 records of significant process in the flat-lying strata of the neighboring 

 hill, in the superficial deposits mantling the valley, in the forms of the 

 land, eventually even in the products of rock decay. Another result 

 was the multiplication of observers and the subsequent application of 

 the science to the promotion of human weal through mining and agri- 

 culture. During this stage the body of observed fact has been and is 

 increasing with unprecedented rapidity, and with the accumulation of 

 fact there has been some increase in hypothesis ; yet the ratio of hypoth- 



