SUPEEFICIAL GEOLOGY OF BKITISH COLUMBIA. 115 



the valley of the Salmon river, and in the nearly parallel one occupied 

 by Tanyabunkut Lake (before referred to), moraines, in some cases 

 nearly parallel to the sides of the valleys, in Others more or less 

 completely transverse to them, occur, with constant evidence of the 

 carriage eastward in quantity, but not to a very great distance, of 

 rock-fragments — granitic rocks, for instance, having been moved 

 some miles eastward and left scattered on the glaciated surfaces of 

 basalt-flows. The evidence of a previous movement of ice westward 

 down the Tanyabunkut valley and towards the coast through the 

 Salmon-river gap, owing to its sheltered position, has not been 

 obliterated by the subsequent eastward flow, which all the evidence 

 tends to show must have been of short duration. 



South-western or Main Branch of the Nechacco River (lat. 53° 25', 

 long. 125° 10'). — The river here issues from a large lake called 

 Na-tal-kuz by the Indians. The lake lies transversely in a range 

 of hills which has a general north-west and south-east course, 

 parallel to the Coast range and other main features of the country, 

 but rising in the centre of a plateau region. To the south-east 

 these hills become mountains about 2000 feet in height above the 

 plateau in some instances. The lake is dammed by moraine-material 

 with rocks appearing in its sides ; and the surface of a small isolated 

 rocky hill near its lower or eastern end shows heavy glaciation from 

 west to east, parallel to the general course of the valley. East of 

 the end of the lake the Nechacco cuts through a mass of moraines 

 which covers a stretch of country probably at least five miles square. 

 The moraines are very little modified, and wonderful in size and 

 state of preservation (fig. 6). The most prominent form ridges miles in 

 length, which, though wavering a little in direction and of variable 

 height, sweep round to the north-eastward in broad curves, to the 

 direction of which the river conforms for some time. The ridges 

 are steep-sided, sloping frequently at an angle of 30° to the bottoms 

 of the narrow sinuous valleys which separate them, and are from 

 100 to 200 feet in height. The best-marked ridges are evidently 

 the successive lateral moraines of a glacier- tongue gradually "de- 

 creasing in width. Besides these, however, there are occasional 

 fragments of transverse ridges, blunter and broader, apparently 

 remnants of terminal moraines formed when the glacier nearly 

 equalled the valley in width. 



It cannot be certainly affirmed that the glacier causing this dis- 

 play of moraines did not owe its origin to the low range above 

 mentioned. Taking, however, all the local circumstances into 

 account, and especially the small gathering-ground afforded by this 

 range, it appears more probable that the Coast-Range glaciers must 

 at one period have pushed a short distance through the gap in which 

 the lake lies. 



Still further north, on the 54th parallel, the valley containing, 

 from west to east, Francois and Fraser Lakes and the lower portion 

 of the Nechacco river, runs from near the eastern base of the Coast 

 range to the Fraser in a remarkably direct line. Francois Lake, 

 further west, is, by my track-survey, fifty-seven miles and three- 



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