64 GROVE KARL GILBERT— DAVIS [MEM0IES n ^ T xxt 



that he had ever been troubled about expressing nimself clearly; yet one of his associates on 

 the Wheeler Survey records that he was at that time " not a ready writer," and that it was only 

 "as a result of care and dfligent labor that he acquired the singularly simple and lucid style 

 which later distinguished all his communications." As to the antecedent difficulty of com- 

 pletely thinking out the various elements of a theory, that also would not be attributed to 

 Gilbert by those who knew his power of exceptionally keen and clear analysis as displayed in 

 later years; yet such analytical thinking appears to have been in this case a serious task in his 

 earlier life. 



There is, nowever, another possible explanation of the deficiency of physiographic presenta- 

 tion. The idea that the ranges were upheaved and more or less carved fault blocks may, after 

 its invention, have appeared to its inventor so simple, so self-evident, that it hardly needed 

 demonstration or explanation. He was only a young and little trained explorer; and if he had 

 come upon this idea in his first field season in the West, or, better said, if the idea had so early 

 in his western inexperience forced itself upon him in place of the incompetent theory that he 

 had brought from the East, how could it fail to be accepted by other explorers ! He had surely 

 talked it over with Powell, and Powell was at once convinced of its value and verity. Indeed 

 how could anyone, on seeing the discordance between the trends of the mountain margins and 

 the mountain structures, imagine that the ranges could be the erosional remnants of great 

 folds ! How could any one fail to see that each range is a unit, sometimes truly a complex 

 unit, of displacement along great fractures that are independent of the range structures! After 

 the truth was once perceived and briefly stated, why spend time in expanding and expounding 

 a matter so manifest ! 



And there is also a third possible explanation, the clew to which is found in a letter that 

 Gdbert, after finishing his second report for Wheeler, wrote late in 1874 to Powell when about 

 to join his survey of the Rocky Mountain region: 



My application for permission to publish some of my data (whether the official report had appeared or 

 not) was negatived by General Humphreys [under whose direction, as chief of engineers, Wheeler conducted 

 his survey], and I feel little ambition to write anything for publication with the uncertainty that would hang 

 about the date of its appearance. 



Gilbert had enjoyed the satisfaction of prompt publication of his Maumee Valley study, 

 which Newberry had approved in the liberally administered survey of Ohio; and the more 

 rigid administration of the Wheeler survey under Army regulations was displeasing and dis- 

 couraging to him. The report on even his first two seasons' field work had not then been printed ; 

 and although it is dated July, 1874, there is reason to believe that it was essentially completed 

 at a much earlier date. It is therefore probable, that under these conditions of formality and 

 delay, the active-minded young scientist was not tempted to elaborate his theoretical views. 

 That he could have done so had he wished to is sufficiently proved by the fullness and prompt- 

 ness with which he completed a critical analysis of the Henry Mountains' problem three years 

 later, when he enjoyed the favoring conditions offered by Powell's survey, as will be told below. 



Hence under any explanation, one must read between the lines if he would appreciate 

 Gflbert's full physiographic meaning; but in thus attempting to discover the tacit basis of 

 the written passages, one runs the risk that attends the composition of all commentaries; the 

 risk of, at a later date, reading into an author's words a larger understanding than he had in 

 mind when he wrote them. Nevertheless, some interpretative comment on the first statement 

 of so interesting and important a problem as the origin of the basin ranges by so able and original 

 an observer and thinker as Gilbert is permissible, even necessary, when the problem is reviewed 

 in the light of nearly 50 following years ; and it has therefore been here undertaken particularly 

 with regard to the physiographic aspects of his work. On that side, it may be confidently 

 believed that his understanding was much greater than his presentation explicitly announced. 

 If it be objected that, if this were true, he should have in his later writings made claim of the 

 larger understanding that he had originally possessed, it may be confidently answered that, 

 however much more he had known than he had said, he would have let his early reports stand 

 at their face value; for, as already noted, the making of claims was not in his nature. 



