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In :Monograpli XXXVIII. U. S. G. S.. Mr. Frank Leverett lias mapped 

 and given a brief description of the prolialde preglacial drainage, tlie areal 

 extent of tlie lalving and the tinal adjustment of the postglacial drainage 

 within tlie counties mentioned above. For the discovery of a few of the 

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

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

 and Owen counties. Mr. Siel»e.ntlial has also referred to this same topic 

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

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

 the description and discussion presented in. tliis paper. 



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

 Brown County, flows a little south of Avest to Monroe County, reaching the 

 northwest corner of Elcomington Township, Avhere 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 G-osport, 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 A'ariations 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 course insists upon keeping to the sotith or southwest side or edge 

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

 liunimocks and ridges, the former ustially located near the middle of the 

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

 ley slope. The rock content of these striking 1)its of relief is precisely 

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

 namely, the stibcarboniferous limestone and underlying sandstone locally 

 knoAvn 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 stirface of the upland. Fifth— The 

 development of Y-shaped valleys just scarring the vallej; 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 storv of its life resolves itself into three fundamental parts. 



