330 The Drift or Boulder Formation, 



level plain, the strike side, or that which was exposed to the 

 current, has been swept clean, while the lee side has a long ridge 

 of drift stretching away from it. Such mountains are called 

 " crag and tail," and from the little we have seen of the hill in 

 question, we think it affords a good example. The Barrack Hill, 

 at the City of Ottawa, is another, but with the tail turned towards 

 the south-east, extending in a line running from the old military 

 hospital in the direction of the canal basin. 



The courses of the glacial striae in the valleys of the Ottawa 

 and St. Lawrence, so far as we have observed them, are at right 

 angles to each other. On the Barrack Hill, in the City of Ottawa, 

 at the village of New Edinburgh, at Stegraan's Rapids, on the 

 Rideau, five miles from Ottawa, near the first toll-gate on the road 

 to A3^1mer, in the Township of Hull, and also in the Township of 

 March, we have seen them, and in all these localities their course 

 is from the north-west towards the south-east. Further up the 

 Ottawa, on \h.e, road between the village of Renfrew and Burns- 

 town, and also in the Township of Ross, they have the same 

 bearing. It thus appears that while the glacial stream ran down 

 the valley of the Ottawa it flowed up the St. Lawrence, a state of 

 things which would lead to one more of those complexities which 

 have so long made the question of drift the most unsettled one in 

 geology. 



Where these strise are found in valleys bounded on each side 

 by shores of rock, they often follow the windings of the ravine as 

 if it had been the channel of a stream. A remarkable instance of 

 this fact was observed by Sir W. E. Logan, while examining the 

 geology of the upper part of the Ottawa. Under the head of 

 " GlaciaV Action,^'' he states : — " Fresh water shell marls occur in 

 many places in the alluvial deposits of the Ottawa, and among the 

 phenomena which come within the recent period, rounded and 

 polished rock surfaces, bearing parallel grooves and scratches, are of 

 not unfrequent occurrence. They were met with on the Gatineau, 

 half-way between Farmer's and Blasdell's mills, where the direction 

 of the scratches is about S. 36*^ E.; on Glen's Creek, in Pakenham, 

 where they are about N. and S. ; on the Allumettes Lake, at 

 Mongomery's Clearing, where they are S. 25^ E. ; but on the 

 shores of Lake Teraiscamang they are so numerous, and are com- 

 bined with other circumstances of so marked a character, as to 

 deserve particular notice. The lake has already been described 

 as long and narrow. Its banks are in general bold and rocky, 



