114 GEORGE MERCER DAWSON" ON THE 



Thompson Valley. — The river flows south-westward to its junction 

 with the Eraser at Lytton. Fragments of the rocks of the Cascade 

 mountain- series, in the form of large and small boulders, produce 

 a rather irregular but evident moraine overlying rocks of a different 

 character, twenty-four miles above Lytton. 



The glacier, in both the above cases, must have crossed the deep 

 valley of the Eraser ; but the localities to which it has here reached 

 can scarcely be said to be beyond the eastern flanking mountains of 

 the Coast range. 



Chilcotin Valley (lat. 52°). — Moraines can be traced here with 

 certainty as far as the lower end of Tatla Lake, and with great 

 probability to the outflow of Puntzee Lake. The former locality is 

 situated twenty-five miles from the eastern base of the Coast range, 

 and fifty miles from its central region ; the latter forty miles from 

 the eastern base. There is considerable reason to believe that the 

 moraines of these places have been formed by a glacier pushing out 

 into water, and somewhat modified by water-action, either con- 

 temporaneously or immediately after their formation. A congeries 

 of small ponds, lakes, and swamps, called the Buckhorn Lakes, 

 owes its existence to the steep-sided hollows, cup-shaped, trench- 

 like, or crescentic, enclosed between moraine ridges. Many of these 

 ponds have no visible outlets. A sheet of water six miles in length, 

 called Eagle Lake, is dammed at its eastern end by moraine- 

 material, in which very large angular blocks, evidently derived 

 from low rocky hills at the sides of the valley, form a prominent 

 ingredient. The watershed between the Homathco river, flowing 

 directly through the Coast range to the sea, and branches of the 

 Chilcotin, flowing eastward to the Eraser, lies just within the 

 eastern foot-hills of the Coast range, is low, and apparently 

 composed altogether of drift-material, more or less evidently 

 morainic. It is probable that before the Glacial period the waters 

 of a great extent of country now draining towards the Eraser, flowed 

 by the gorge of the Homathco through the Coast range. Lakes 

 and pools without outlet, irregular morainic hummocks and ridges, 

 projecting to a greater or less height through flat or gently undu- 

 lating deposits formed from their waste, characterize equally the 

 sources of the east and west branches of the Homathco. A general 

 movement eastward from the valleys of the mountains can be proved 

 from the composition of the drift. 



BlacJcivater and Salmon-River Valleys (approximate latitude 55°). 

 ' — The tributaries of these rivers interlock about the 125th meridian, 

 the former flowing eastward to the Eraser, the latter westward, I 

 through the Coast range. Moraines which appear, without doubt, I 

 to belong to the Coast-Mountain glaciers, occur beyond the low 

 watershed on the tributaries of the Elackwater, at a distance of I 

 forty-five miles from the eastern base and sixty-five from the central 

 peaks of the range. These are seen in the neighbourhood of Tsi- 

 toe, Klootch-oot-a, and other small lakes of the same group. Six- 

 teen miles further westward, at Uhl-ghak Lake, glaciation with a 

 course of K". 80° E., evidently referable to this period, occurs. In 



