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BULLETIN OF THE NATURAL HISTORY SOCIETY. 
rapids, the same varied banks, now low intervale points, now 
glacial terraces, and again steep sandstone cliffs cut by the on- 
charging river. Here, too, the valley walls, though far enough 
apart to permit much minor winding of the river between them, 
are steep, and cut abruptly into a plateau, which is now somewhat 
lower and again higher, possibly at times approaching two hund- 
red feet. So far as can be seen from the valley itself, this section 
of the river is of the same age as that above it. This is an un- 
expected result, for in my earlier discussion of the origin of the 
Northumbrian rivers I gave reasons for believing that this 
section of the Tabusintac , together with the Big Escadelloc, and 
as well the lower turn of Big Brook lying in a direct line with 
it, all occupy a part of one of the ancient Northumbrian valleys. 
Moreover, I had found this idea to a great extent confirmed when 
I observed that the Big Escadelloc, where crossed by the Bathurst 
road, occupied a very wide, deep, ancient-looking valley, a far 
older and wider valley than that occupied by the Tabusintac on 
the same road. Accordingly I am inclined to believe that this 
division of the Tabusintac, from Escadelloc to Big Brook, 
occupies a valley newly cut, “ rejuvenated,” into the floor of an 
older Northumbrian valley, though I admit there are difficulties 
in this interpretation. 
Below the Big Hole Brook the river still continues of the 
same general character, though ever enlarging and growing 
gentler in current, while the plateau becomes gradually lower. 
Then, a mile or two above Trout Brook (and not below it, as 
shown on the plans in the Crown Land Office), the well-nigh 
imperceptable current of the river merges with the tide, with 
hardly a sign to mark their union, save only some water-logged 
wood upon the bottom. Below the head of tide the valley keeps 
still the same character, though the tidal stillwaters fill it now to 
the abrupt walls. Thus it continues down nearly to Stymest’s 
Millstream, when it somewhat abruptly opens out into another 
character. It is thus plain that all this division from Big Hole 
Brook, no doubt including also that brook, is of the same age as 
the parts above the Escadelloc — pre-glacial, and old, but much 
newer than the ancient Northumbrian valleys. 
Comparing the Tabusintac, above the tide, with its sister 
