102 GEORGE MERCER DAWSON ON THE 



on one spot, protected by a foreign boulder, which had to be over- 

 turned before it could be observed. The glaciated surface is con- 

 siderably inclined and beautifully polished, with faint scratches 

 crossing each other at small angles. The abrupt southern face, and 

 the more gentle northward slope of the hill, appear to show that the 

 ice must have moved southward. Prom N. 30° E., round to N". 18° "W. ; 

 and beyond, the highest country within many miles is a ridge with 

 an elevation from 100 to 300 feet greater than that of the Sinter 

 Knoll ; and beyond this only low blue hills are seen at a distance 

 estimated at from fifteen to twenty miles. 



One of the most remarkable localities in which glaciation referable 

 to this system was found, is a rocky hill south of the Salmon or 

 Dean river, isolated from the higher parts of Tsi-tsutl Mountain, 

 of which it forms an outlier, by a shallow valley about a mile wide. 

 The altitude of this point is 3700 feet. "Westward the view is 

 across the lower broken country of the Tahyesco river to the snow- 

 clad eastern parts of the Coast range at a distance of from twelve 

 to fifteen miles. A line drawn south-westward would cross 

 obliquely this wide valley for many miles before higher country 

 would be reached. To the north, the lower region and minor 

 elevations, mentioned in connexion with the last locality, are over- 

 looked. The rocky surface of this hill has been smoothed and 

 striated by ice moving S. 37° "W"., forced apparently somewhat out of 

 its usual course by the flank of Tsi-tsutl Mountain, and passing 

 between it and the Coast range. 



Near Hatty Lake, nearly 1000 feet lower than the last locality, 

 and sixteen miles north-east of it, in a narrow pass between cliffs 

 of hard Mesozoic rocks, ice has left unmistakable traces of its 

 passage south-westward, glaciating not only horizontal, but nearly 

 vertical rock-surfaces. It has conformed in its direction to the 

 tributary valley of Salmon river, in which it is seen, the valley 

 being nearly parallel to the main direction of that of the Salmon 

 river, which runs towards the Coast range, and through it to the 

 sea. 



Glaciation clearly referable to ice spreading from the Cascade or 

 Coast Mountains, and other ranges, is met with in many places ; and 

 generally speaking, wherever circumstances admit of their observa- 

 tion, grooving and striation parallel to the main courses of the valleys, 

 and depressions radiating from or passing through all the higher 

 mountains, may be found. These facts, however, possessing only a 

 local interest, need not be detailed here. Other features of local 

 glaciation will be again referred to. 



b. Superficial Deposits. 



Preglacial Gravels. — It is quite probable that in many localities 

 deposits of Preglacial date, but newer than the basalt-flows which 

 appear to have closed the Miocene period, may occur, especially in 

 deep and steep-sided valleys. A hasty examination of the Cariboo 

 gold-mining district appears to show that while in some valleys, 

 especially those facing northward (e. g. Mosquito Creek), Boulder- 



