About fifteen miles above Yale, the gorge through which the Fraser runs, as it bursts through the Cascade Range, becomes very narrow, and the river flows in a succession of terrific rapids, called the Cañons-- or _canyons_, as the word is pronounced--for the remaining distance. The mountains on each side, 3,000 or 4,000 feet high, seem almost to meet overhead, peak after peak rising in close proximity. The Fraser, rarely anything but a rocky rapid in any part of its course, here goes utterly mad, and foams and rages down the narrow and falling channel at the rate of twenty miles an hour. The volume of water which passes through this outlet, here not more than forty yards in width, will be more readily conceived when it is stated that the Fraser has already collected the waters of over 800 miles, and amongst other rivers receives the Thompson, of almost equal size with itself. Several hundred miles above, each of these rivers expands into a broad and deep stream, more than a quarter of a mile in width; yet at the Cañons the vast accumulation is confined in a channel of less than fifty yards wide. Huge rocks stand up in the middle of the stream in several places, the waters escaping by a constricted passage on either side. The mass of the Cascade Range is grey granite, and the sides of the chasm show beautiful sections of the rock, plaided with protruding seams of white quartz, the harder rock having been worn away by the action of the water, which the soft quartz seems to have resisted. In many cases the opposite walls of the chasm correspond in a most remarkable manner, so that they appear as if they would fit accurately if placed in apposition, suggesting forcibly that they had been portions of the same solid mass violently rent asunder. As we looked on this and wondered, an explanation of the formation of the terraces occurred to our minds. At one time the valleys of the Thompson and Fraser were occupied by a succession of lakes, the Cascade Range being the barrier which dammed in the enormous volume of water, and the highest tier of terraces marking the level to which it rose. The tops only of the lower mountains appeared at this time as rounded islands above the surface. By some means--perhaps some grand convulsion of Nature--the embankment of this huge reservoir broke down, the waters partially escaped, and the lakes were drained down to the level of the middle tier of benches. Twice more must a similar catastrophe have occurred before the waters were lowered into their present narrow and rocky channel. Each of these accidents must have been separated from the preceding one by an immense lapse of time, during which the enormous quantity of detritus accumulated to form the extensive plateaux which have been described. [Illustration: YALE, ON THE FRASER RIVER. (_See page 347._) ]