No. 30.] STILL RIVER. 35 



The lowland lying west of Umpog valley, extending from 

 Main Street in Danbury to a point one mile beyond Bethel, affords 

 no definite evidence in regard to the direction of tributaries. In 

 reconstructing the history of this valley the chief difficulty arises 

 from the old-age condition of the flood plain. Drainage channels 

 which must once have existed have been obliterated, leaving a 

 swampy plain which from end to end varies less than 20 feet in 

 elevation. It is likely that in preglacial times the part of the 

 valley north of Grassy Plain, if not the entire valley, drained 

 northward into Still River, as now do Umpog Creek and Beaver 

 Brook. From this outlet heavy drift deposits near the river 

 later cut it off. The lowland is now drained by a stream which 

 enters the Umpog north of Grassy Plain. Several small streams 

 tributary to the Umpog south of Bethel also furnish no evidence 

 in favor of the reversal of Still River. 



West of Danbury the tributaries of Still River point upstream 

 on one side and downstream on the other side of the valley, in 

 conformity with the rock structure which is here diagonal to the 

 limestone belt on which the river is located. Their direction in 

 harmony with the trend of the rocks has, therefore, no sig- 

 nificance in the earlier history of the river. 



From the foregoing discussion, it appears that no definite 

 conclusions in regard to the history of Still River can be drawn 

 from the angle at which tributaries enter it. The direction of the 

 branches which enter at an a'bnormal angle can be explained with- 

 out assuming a reversal of the main stream, and likewise many 

 of the tributaries with normal trends seem to have adopted their 

 courses without regard to the direction of Still River. 



3. REGIONAL SLOPE NOT IN ACCORD WITH COURSE OF THE STILL 



Although the regional slope of western Connecticut as a whole 

 is contrary to that of Still River, there is no marked lowering of 

 the hill summits between the source of the river and its mouth. 

 As branches on the south side of the Housatonic are naturally to 

 be expected,, there is nothing unusual in the Still flowing in 

 opposition to the regional slope, except that it flows toward the 

 north instead of the northeast. 



