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In Monograph XXXA'III. U. S. G. S., Mr. Frank Leverett has mapped 

 and given a brief description of the probable preglacial drainage, the areal 

 extent of tlie hiking and the final adjustment of the postglacial drainage 

 within the counties mentioned aliove. For the discovery of a few of the 

 cases described, Leverett is indebted to ^Ir. C. E. Siebenthal. who fur- 

 nished much of the data relative to the laked valleys found in Monroe 

 and Owen counties. Mr. Siebenthal has also referred to this same topic 

 in a paper published in the annual reports of the Indiana State Geological 

 Survey. It rs to one of these cases that I wish to devote the main part of 

 the description and discussion presented in this paper. 



Bean Blossom River takes its rise in the northern tier of townships in 

 Brown County, ilows a little south of west to Monroe County, reaching tlie 

 northwest corner of Bloomington Township, where it turns rather sharply 

 and continues in a due northwest course to the White River, into which 

 it empties at a point about one mile below Gosport, Owen County. The 

 topographic features of this rather picturesque valley, which are regarded 

 as giving the key to its geographic history, are, briefly, these: First— The 

 steepness of the valley sides and its persistence in close contact with the 

 valley floor, together with its peculiar variations in direction. Second— 

 The predominance of a broad flat floor, sometimes a mile or more in width, 

 now occupied by a small meandering stream which for the greater part 

 of its cour.xe insists upon keeping to the south or southwest side or edge 

 of the valley floor. Third— The occurrence of both isolated and attached 

 hummocks and ridges, the former usually located near the middle of the 

 valley floor, the latter standing in rather close proximity to the val- 

 ley slope. The rock content of these striking bits of relief is precisely 

 the same as that which composes the upland on either side of the valley, 

 namely, the subcarboniferous limestone and underlying sandstone locally 

 known as the "knobstone." Fourth— The occurrence of a series of benches 

 or so-called terraces rimming the valley slopes at various points and rang- 

 ing in height above the valley floor from thirty to seventy feet. These con- 

 sist of mixtures of sandy material and clay which have been derived from 

 the rock formations as appear on the surface of the upland. Fifth— The 

 development of Y-shaped valleys just scarring the valley sloped to the 

 present valley floor and not extending beneath it. 



In attempting to unravel the geographic history of a river valley whose 

 drainage has been subject to arrest by the invasion of an ice sheet, we find 

 that the story of its life resolves itself into three fundamental parts. 



