54 CONNECTICUT GEOL. AND NAT. HIST. SURVEY. [Bull. 



till overlying it higher up. The more usual arrangement is 

 boulder clay overlain by modified drift, the first being laid down 

 by the ice itself, the second being deposited by streams from the 

 melting glacier in its retreat. Huge boulders, many ten feet or 

 more in diameter, are strewn over the northern slope of Shelter 

 Rock. 



DEPOSITS NORTHEAST OF DANBURY 



North of the railroad, opposite Shelter Rock (fig. 6), is a 

 most interesting flat-topped ridge of drift which topographically 

 is an extension of the higher rock mass to the northwest. In this 

 drift mass are to be found in miniature a number of the forms 

 characteristic of glacial topography. The broad-topped gravel 

 ridge slopes sharply on the north into a flat-bottomed ravine 

 which is evidently part of the Still River lowland. This portion 

 of the valley has been shut off by drift deposits. The drainage 

 has been so obstructed that the stream in the ravine turns north- 

 east away from its natural outlet. In the valley of " X " brook 

 (fig. i) are terraces, esker-like lobes, and detached mounds of 

 stratified drift resting on a foundation of till. 



Along the eastern border of the hill is to be seen the contact 

 between two forms of glacial deposits (PI. IV, B). A mass of 

 stratified drift overlies a hummocky deposit of coarse till, but 

 large boulders occurring here and there on top of the stratified 

 drift show that the ice-laid and water-laid materials were not 

 completely sorted. Boulders seem to have been dropping out of 

 the ice at the same time that gravel was being deposited. Boul- 

 ders of granite-gneiss eight feet or more in diameter, carried by 

 the ice from the hills to the north and northeast, are strewn at the 

 foot of the hill. 



DEPOSITS BETWEEN BEAVER BROOK MOUNTAIN AND 

 MOUTH OF STILL RIVER 



About a mile beyond Beaver Brook Mountain, the railroad 

 cuts through the edge of a hill 80 feet in height exposing a section 

 consisting of distinctly stratified layers of fine white quartz sand, 

 coarser yellowish sand, and small round pebbles. The quartz 

 sand was used at one time in making glass. Farther east where 



