Reviews . 



Comparison of North American and European Glacial Deposits. 

 By Frank Leverett, Ann Arbor, Mich. Zeits. /. Gletscher- 

 kunde (1910), IV, 241-316; Pis. V. 



Intercontinental comparisons of this class may be made from the view- 

 point of an individual worker, or from that of a representative of a special 

 class of workers, or from that of an analyst of the whole body of current 

 conceptions. Each viewpoint has its appropriate place and value, and 

 each comparison must be adjudged on its own basis. The comparison 

 of Mr. Leverett is individual rather than representative or composite. 

 This gives occasion to note the reach of the personal studies that form the 

 basis of the author's perspective. No one is more intimately conversant 

 with the later glacial deposits of the plains of the United States from the 

 Alleghenies to the Mississippi than is the author of this comparison. With 

 the equivalent deposits east of the Appalachians, west of the Mississippi, 

 and north of the national boundary, the author's familiarity comes rather 

 from occasional excursions and secondary sources than from personal 

 studies. With the older Labradorean formations east of the Mississippi 

 the author's familiarity is also intensive, and this intimate knowledge ex- 

 tends measurably to the tract closely bordering the Mississippi on the west, 

 but not in equal degree to the formations of the Missouri basin, to the 

 glacio-fluvial deposits of the Lower Mississippi valley, or to those of the 

 Atlantic coast. The montane field of western America lies outside the 

 author's individual purview. 



To this intensive basis in American study, Mr. Leverett has recently 

 added a year's inspection of the European formations, with Berlin as a 

 working center and German interpretations as a point of departure. His 

 field studies lay chiefly in the German lowlands and in the Alps, with a 

 very cursory glance at the British field. 



These salient features of the author's experience may serve to orient the 

 psychologic plane from which the comparison is made and to foreshadow 

 the selection, emphasis, and coloration which might naturally arise from 

 the author's point of view. 



In full harmony with these, the preliminary glance over the makeup of 

 the paper brings at once to view the obvious fruits of the intensive habit. 



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