IN KINGS COUNTY, N. S.—HAYCOCK. 291 
recent times now extend for several miles up the drowned 
valleys. That this topography is probably Pre-glacial is indi- 
cated by the occurence of a layer of Boulder clay of variable 
thickness mantling both hill and valley. The changes in topo- 
graphy since the disappearance of the ice of the Glacial period are 
exceedingly slight in this region and are confined almost wholly 
to the deposition, during a subsequent slight submergence, of 
some banks of stratified sand and gravel, some wearing away 
and retreat of the coast cliffs, and the filling-in of the river 
basins mentioned. 
The North Mountain has the prevailing trend of the other 
ridges, and would appear to owe its present elevation above the 
valley to the harder and more resistant character of the sheet of 
voleanic rock, which protects the underlying soft sandstone from 
the action of the eroding agents that have worked with such 
effect upon the unprotected sandstone to the south-east. The 
junction of the sandstone and trap is some two hundred feet or 
more above the floor of tne valley, and the conviction is forced 
upon the observer, when looking south-eastward from this point. 
that not only the smaller valleys mentioned but also the whole 
broad depression he has crossed has been worn out of the soft 
red sandstone, and that excepting minor inequalities of surface 
the present relief of this part of the Province is wholly due to 
differential resistance of the underlying rocks. 
The trap sheet retreats more rapidly along its edges than 
the sandstone owing to frostwork and its vertical jointing, and 
when they both appear in the face of the escarpment the over- 
lying trap is never overhanging but always well behind the 
sandstone which generally forms a steep slope upon which the 
fragments of the trap are precipitated, forming broken masses 
which conceal the contact of the two formations. Because of 
the soft nature of the sandstone and its calcareous cement it 
weathers much more rapidly than the trap wherever exposed to 
the action of rain and wind, but since the jointing is not well 
developed it is not affected to a very great extent by the action 
of the frost. 
