432 ■ THE JOURNAL OF GEOLOGY. 



essential branches of the science. Major Powell has himself, as 

 an individual investigator, been one of the pioneers in this new 

 departure, and the doctrine of the base-level, which we owe so 

 largely to him, taken with its corollaries, constitutes one of the 

 most important contributions of recent decades. In so far as 

 the topographic work of the Survey has become an adjunct and 

 antecedent of the new physiographic phases of geology, it mer- 

 its the highest commendation. In so far as it has fallen short of 

 this, it perhaps expresses the practical difficulty of at once ren- 

 dering topographical work geological, a difficulty not to be won- 

 dered at since topographical work has been so largely regarded 

 as a function of some other science than geology, some science 

 in which the mere hypsometrical factors of relief, mechanically 

 represented, have been chiefly considered instead of the genetic 

 factors that give meaning to the topography. Until a genera- 

 tion of geological topographers can be trained up, topographic 

 work cannot be expected to be other than mechanical and rela- 

 tively expressionless. It may be questioned whether some of 

 the topographic effort that has taken the extensional form might 

 not better have taken an intensive form in the interest of trans- 

 muting mechanical topography into geological topography, or, 

 in other words, the substitution of genetic expression for mean- 

 ingless mechanicalism. But, withal, the great development of 

 the topographical side of the Survey has been in the line of 

 progress and the needed transformation in the fundamental 

 nature of the work should grow out of it through persistence in 

 the educative process already begun. We have no sympathy 

 with the geologist who looks upon topographic work as an 

 alien function to be performed by those whose profession does 

 not lead them to know how topographic relief was produced or 

 what it means, and who carps at the Survey for an alleged inva- 

 sion of fields outside its domain. 



Under Major Powell's administration, the physical and philo- 

 sophical phases of the Survey have received a more marked im- 

 petus than the palaeontological, though an able and active corps 

 of palaeontologists have always formed a large division of the 



