June 17, 1910] 



SCIENCE 



945 



mined by experiment, which I should like 

 very much to see tried. In any case, we 

 can gain no comprehension of large regions 

 save by gathering and by generalizing ob- 

 servations of small visible landscapes. It 

 is fair to expect that the better our under- 

 standing of detailed morphology, the better 

 we can summarize general features. My 

 own experience in describing the larger 

 subdivisions of the United States and of 

 Europe would encourage me to say that the 

 explanatory method can be well used for 

 the treatment of such areas; but I have 

 made few sj'stematie experiments with any 

 other method of description. 



Another geographer has expressed his 

 fear that an explanatory method of de- 

 scription for land forms will prove danger- 

 ous in the hands of untrained students, 

 and that young disciples may apply it in a 

 way that will cause anxiety at first and 

 horror afterwards. Horror is rather a 

 strong word to use in this connection; but 

 I can instance several examples that have 

 caused me some anxiety, and others which 

 have, I am sorry to admit, shocked me, to 

 say the least. There is the ease, for ex- 

 ample, of a geographer who, inasmuch as 

 he submitted an article to me for criticism, 

 and accepted the criticisms that I made, 

 may perhaps be regarded as a disciple to 

 that extent ; but surely he caused me some 

 anxiety by stating in essence that "gran- 

 itic districts are of rugged form." His 

 evident error here was the failure to con- 

 sider the erosional process and the time 

 element, or stage of erosional development, 

 in his partly explanatory treatment; for 

 resistant as granite is, rugged as its forms 

 may be in a youthful stage of normal ero- 

 sion, and sharp as they may be in a mature 

 stage of glacial erosion, granite must have 

 subdued and rounded forms in late ma- 

 turity; and like every other kind of rock, 

 even the hardest granite must be worn 



down to low relief of veiy tame expression 

 in old age, as abundant examples testify. 



In another case a geographer who ex- 

 plicitly declared himself to be my disciple 

 shocked me by the additional declaration 

 that the scheme of the cycle of erosion, 

 which is essentially involved in the method 

 of structure, process and stage, must be 

 inapplicable to districts in which frequent 

 movements have taken place, because for- 

 sooth he thought that the scheme of the 

 cycle could be used only where complete 

 cycles ran their course! In both these 

 cases and in various others of a similar 

 kind, criticism ought not to be directed 

 against the explanatory method of descrip- 

 tion, but against its wrong use. It is 

 proverbial that "a little learning is a dan- 

 gerous thing"; the proper guard against 

 such danger is better found by decreasing 

 the careless use of an explanatory method 

 than by discouraging its careful develop- 

 ment. 



And finally, to close these comments with 

 one that suggests a most peculiar attitude 

 on the part of the critic, it has been ob- 

 jected that the method of structure, process 

 and stage can not be applied until one 

 knows all about the district that he is de- 

 scribing. In so far as the use of the 

 method may require an observer to make a 

 serious study of a district before he at- 

 tempts to tell about it, the method is 

 thereby recommended; but as a matter of 

 actual experience, the explanatory method 

 has proved useful even in the most hasty 

 reconnoissance, because it aids so greatly 

 in directing observation to significant 

 points, which might as likely as not escape 

 the attention of a blind empiricist. 



The kind of criticism that the method of 

 structure, process and stage really needs 

 is, as has already been intimated, criticism 

 based on the experimental and comparative 

 use of various methods, each method being 



