20 W. H. HOBBS — STILL RIVERS OF WESTERN CONNECTICUT 



mile of the river's course represent a total fall of about 100 feet. The 

 stream empties at Robertsville into Sandy brook, one and one-half miles 

 above the latter's junction with the Farmington. The Still meets the 

 Sandy in a direction at right angles to its course. The pebbly bed 

 of Sandy brook is here in striking contrast with the cascades by which 

 the waters of the Still gain its level. For all save the extreme northern 

 portion of its course, the Still river flows in a deep valley, the walls 

 of which rise rather steeply 400 to 500 feet, though it is observed that 

 the eastern slopes are less steep than the western. Near its outlet into 

 Sandy brook this trough loses its distinctive characteristics. 



At Winsted, 4 miles above its outlet, the Still receives the waters of 

 the boisterous Mad river, which, starting at Summit station in Norfolk, 

 flows 8 miles in a deeply incised valley to the junction with the Still, 

 during which flow it falls 600 feet, an average of 75 feet to the mile. 

 The deeply incised valley of Mad river is prolonged beyond the junction 

 with the Still by the similar valley of Mohawk brook, a direct tributaiy 

 of the Farmington. The divide between the Still and the Mohawk is a 

 low drift barrier, which closes the entrance to the latter from the former. 

 The deeply cut valley troughs of the Still and of the Mad-Mohawk thus 

 produce a nearly right cross, at the center of which is the city of Winsted. 



CONDITIONS DETERMINING THE STREAM'S COURSE 



There is an indication that the valley of the Still has been given its 

 direction by a narrow belt of limestone inclosed between walls of gneiss. 

 Of this belt only half a dozen scattered remnants are now to be found. 

 Theii* positions are indicated on the map (figure 1) by the crosses. 

 These narrow lenses, Avhich are still preserved, are believed to represent 

 the remnants of a trough infolded in the underlying gneiss. On this 

 assumption these areas would formerly have been continuous and have 

 formed a belt, the area of which at the beginning of the cycle may have 

 been as large or larger than the present valley. Some indication of a 

 second and parallel belt is perhaps afforded by the two small exposures 

 of limestone farther to the east, the one about a mile east of Winsted and 

 the other on the Ramsbottom place, approximately the same distance 

 east of Robertsville. 



The Mad-Mohawk valley takes the normal direction for a stream 

 tributary to the Farmington. The valley 'of the Still is an extension of 

 that of a small eastern tributary of the east branch of the Naugatuck, 

 and its life history is best interpreted by assuming that the erosion of 

 the Still valley was begun by the Naugatuck, which, working in the 

 softer and more soluble dolomite, acquired an advantage over that 

 branch of the Farmington Avhich occupied the Mad-Mohawk valley. 



