228 



slopes now stand some 80 to KH) feet above the valley floor. If this view 

 be correct, it would seem altogether probable that the main stream, Bean 

 Blossom, inasmuch as both flow over the same kind of rocks with the 

 same structure and texture, had also passed through the same stages as 

 did its tributary. 



But so deeply has the valley been ttlled after grade was reached that 

 such meander-cut slopes as were developed have been largely buried be- 

 neath the present fllling. Either, tlien, Bean was early at grade and 

 widened its valley Ijy meandering, or after it came to grade was compelled 

 to incise its meanders, nearly all of which have been subsequently buried 

 beneath its present valley floor. 



Moreover, so deeply has Bean Blossom been aggraded that many of 

 the tributary valleys are also aggraded for some distance up stream. This 

 wholesale filling would necessarily force the slopes to rapidly retreat at 

 the junction of the ti'ibutary with the main stream, so that, as a result, 

 the trend of the valley sides would assume a systematic angularity. The 

 consequent narrowing and broadening is well exhibited in the lower ten 

 miles of Bean Blossom, 



LOST RIDGES AS EVIDENCE OF AGGRADING. 



It is evident, should a valley be refilled, in part, with waste fi'om the 

 uplands, that any relief left between its valley slopes, as well as the dis- 

 sected slopes included, would lose relief in proportion to the amount of fill- 

 ing brought into the valley. In such a case we should expect to find many 

 successive stages of burial of the dissected slopes, according as they were 

 near or remote from the center of the prefilled valley. Many of these 

 stages are well shown in the lower portion of Bean Blossom. 



In the middle of Bean Blossom valley occur a number of illustrations 

 in which the inter-stream spaces of moderate relief have been so deeply 

 buried that the uppermost portion of the same now stands above the valley 

 floor, as isolated ridges or "islands," with very steep side slopes, extending 

 to and beneath the present floor of the valley. These are locally spoken 

 of as "lost ridges," a term quite appropriate to their geographical history. 

 Such islands are shown in a number of sketch maps. In sketch map I a 

 small subcircular knob (Section .5, Bean Blossom Township) stands in line 

 with a point standing between "White River on the left and Bean Blossom 

 on the right. Its position suggests that it is the buried end of this point 

 (see Plate No. 1). 



