Reviews 



"The Wisconsin Drift Plain in the Region about Sioux Falls, 

 South Dakota." By J. Ernest Carman. Proc. Iowa Acad. 

 Sci., XXVI (1913), 237-49. 

 It sometimes happens that questions of no great moment in them- 

 selves — and these chiefly local — come to play a more conspicuous part 

 in the literature of a science than their real importance warrants simply 

 because someone has seen fit to emphasize them unduly and has made 

 them the ground of unwarranted impressions of the delinquencies of 

 predecessors who kept them more nearly in their proper proportions. 

 This paper of Carman's is an appropriate contribution to the geology 

 of a corner of Iowa and of the adjacent regions, and is fittingly pub- 

 lished in the Proceedings of the Iowa Academy of Sciences. In addition 

 to this appropriateness and local value, it acquires some general interest 

 as an antidote to impressions less well founded and less appropriately 

 given to the scientific public. The question chiefly discussed has so 

 much of importance as may attach to the precise limits to which the Wis- 

 consin drift extended in the region named and to local phenomena inci- 

 dental to this. To the general student of geology it is of little moment 

 whether a given ice advance stopped at a particular line or went a few 

 miles farther, if no special significance is attached to the precise extension 

 and localization. In the case in hand, it appears that some three decades 

 ago Chamberlin and Todd, as a part of extensive reconnaissance work 

 intended to outline the essential features of the Wisconsin ice invasion, 

 mapped and described the approximate border of the Wisconsin drift 

 in the Sioux Falls-Canton region of southeast Dakota, that later they 

 introduced slight modifications of the original mapping, and that Wilder, 

 of the Iowa Survey, introduced other variations, as did also some others, 

 none of which had more than local value. Perhaps the only feature of 

 general interest was the slight lobation of the glacier implied by the 

 border of this drift, in which all these were agreed. Shimek, however, 

 in a paper read before the Geological Society of America and printed in 

 Bull. G.S.A., XXIII (1912), 125-54, made it appear that these differ- 

 ences were of a more serious order and summed up his "more important 

 conclusions" with dogmatic impressiveness (p. 154). It now appears 



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