218 BR. W. ELLS—SANDS AND CLAYS OF THE OTTAWA BASIN. 
about Clear lake. From the aspect of the whole country in this direc- 
tion it would appear as if the waters of the whole Ottawa basin extended 
to the range of the Brudenell hills, and that the area was directly open 
to the Saint Lawrence. The elevation of the Brudenell ridge is about 
600 feet above Clear lake, or rather more than 1,300 feet above the sea. 
In traversing the valley of the Ottawa from lake Temiscaming east, 
nearly to its mouth, one of the most striking features in this connection 
is the presence of former channels. These have now, to a large extent, 
become filled with sand and gravel. The valley of the Ottawa itself is 
a very old one, since the Paleozoic formations as far back as the Cal- 
ciferous, have been deposited there subsequent to its delineation. Along _ 
_that part of the river between the Rapides des Joachim and High View, 
which is about 20 miles west of Pembroke, the channel is now very deep, 
and this portion goes by the name of the “ Deep river.” The river in 
this part follows a nearly straight®course for 30 miles, and the hills on 
the north side are in places nearly 1,000 feet high. The south side, how- 
ever, is generally low and comparatively level, with great areas of sand 
plains. Above High View there is a depression on the south side which 
leads into the lower part of Chalk river, and here the sand deposits are 
very heavy. This depression at one time apparently formed one of the 
channels of the Ottawa. Similar old channels are to be seen at the Roche 
Capitaine and at the Des Joachim, which are farther west. A very pro- 
nounced old channel, now blocked with sand and gravel, is seen at 
Pembroke, where the river in its present course sweeps off to the north 
along the south side of Allumette island. The old Pembroke channel 
kept a nearly straight line for 30 miles, and is now indicated by the 
Muskrat river and lake and by a chain of small lakes which extends east- 
ward past the great bend around the east end of Calumet island. Many 
of these small lakes in the line of the old channel are reported to be of 
great depth, and these are now separated by sand bars. The country 
along the present channels of the river from Bryson west is now largely 
sand-covered on the north and clay-covered along the south shore. The 
channel of the Ottawa on the north side of Calumet island is almost 
entirely in sand, while the greater portion of Allumette island, opposite 
Pembroke, is also largely occupied by sand deposits. 
Along the valleys of the Ottawa and of its several tributary streams 
these sands and grayels, as also many of the clays, are underlain by de- 
posits of boulder clay, and on the north side of the Brudenell ridge a 
thick deposit of black clay apparently represents the decomposition in 
place of thick beds of Utica shale which are found along the north side 
of the range to the south of Clear lake, resting against the gneiss and 
granite of the mountain. ‘This valley was at one time evidently largely 
