227 



That the preglacial Bean Blossom valley was very mvch narrower than 

 the present one, is attested to by the occurrences of various knobs and 

 remnants of ridges pi'otruding through the aggraded floor. Some of these 

 are subcentrally located, suggesting that the pretilled valley must have 

 been confined between the slopes of the half-covered ridges and the oppo- 

 site valley slope, thus decreasing the average width of the pre-filled valley 

 by nearly one-half its present cross-section within the limits of Blooming- 

 ton and Bean Blossom Townships. ^Monroe Coimty. 



There are also certain features which suggest that Beau Blossom must 

 have been at grade at a time antedating the completion of the filling of 

 the preglacial valley. 



At a. number of points within tlie limits of Monroe County are to be 

 found curved valley sides extending for a half mile or more, with steep 

 slope, making an angle with the valley floor of thirty-five to forty degrees. 

 Such regularly curved slopes and at such steep angles at once suggest a 

 mcinidcr-CKt slope. 



Moreover, there is no evidence that these slopes have been cut by a 

 meandering stream on the present floor. We must conclude, then, that they 

 antedate the present surface of the valley fioor. and if meander-cut in 

 origin, as the topographic relief very strongly suggests, Bean Blossom must 

 have lieen at grade before the present filling, at least completed, because a 

 meandering liabit is not begun until the stream has already finished its 

 vertical cutting, or, in other words, has cut down the slope of its channel 

 to such a gentle descent that it could not be lessened. .Then it was that 

 Bean Blossom must have begun its side cutting and carved the cin-ved 

 slopes, only remnants of which are now seen projecting above the level of 

 the present valley floor. 



Another set of facts also points toward the conclusion that the pre- 

 glacial Bean Blossom had reached grade and become a mature stream 

 long before the laking or the completion of preglacial filling of the valley. 



A small triliutary (Jack's Defeat) running northeast from Steinsville 

 presents some features evidently of interest in connection with the geo- 

 graphical history of Bean Blossom. This stream, now rather diminutive, 

 runs upon a flat floor, and hence at grade. The topography, however, of 

 the valley slopes reveals incised meanders. The present slopes are steep 

 and sharp cuspate points now project into the valley on either side. Such 

 only could have been produced by a stream that had at some time reached 

 grade after the incision of its meander. The crests of the meander-cut 



