404 



up as the mouth of Falls Brook and the presence of a long 

 series of rapids and cascades above it, and the change in the 

 character of the valley walls at the mouth of Falls brook, 

 indicates that the lower part of the gorge of the St. John 

 was once part of the valley of Falls brook and that this 

 portion of the valley is of pre-Glacial age. The existence 

 of this valley appears to have been one of the factors that 

 caused the St. John to carve out its new valley. In doing 

 this the St. John lowered the original gradient of the lower 

 part of Falls brook so that the valley of this brook is now a 

 hanging valley. Where the St. John entered the valley of 

 Falls brook, a fall was established which has since receded 

 to its present position, 2,800 feet (850 m.) upstream. 

 Eventually these falls may retreat as far as the pre-Glacial 

 site of the river above the falls. If this should occur, the 

 St. John would speedily re-excavate the upper portion of its 

 course. 



The exit of the gorge of the St. John may be seen from 

 the top of the steep banks overlooking the river about 200 

 yards (180 m.) east of the railway station. This view 

 point is situated close to the western slope of the old valley 

 of the St. John for a succession of rock ledges outcrop 

 along the western shore and bounding slopes that stretch 

 in a straight line to the south. To the east, distant about 

 600 yards (550 m.), the rock-walled mouth of the gorge of 

 the St. John is visible where it enters at right angles into 

 the older course of the St. John still occupied by the river. 

 Between the rock cliffs at the mouth of the gorge on the 

 east and the steep slopes on the western side, there runs a 

 curving escarpment convex towards the north whose 

 crest lies about 200 feet (60 m.) above the waters of the St. 

 John. This escarpment has been formed in the unconsoli- 

 dated material filling the abandoned portion of the river 

 channel. The upper part of this escarpment is cliff-like 

 and is there seen to be composed of bedded sands and 

 gravels. The lower, greater part of the escarpment is 

 mantled by talus and the nature of the material occupying 

 the lower part of the old valley cannot be directly deter- 

 mined. It is assumed that it is of the same character as 

 that filling the upper portion. That the thickness of this 

 material is no greater than the height from the level of the 

 St. John waters to the top of the escarpment, is indicated 

 by the outcrops of rock occurring at the foot of the talus 

 slope along the side of the river. These rock outcrops are 



