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underlying rock. The terraces are carved out of superficial sands, gravel,
and boulder clay. The high hills that extend above them are carved
partly out of the superficial deposits, but mainly out of the hard and re-
sistant bedrock. The surface form also betrays the structure of the bed-
rock. The high, flat, or gently sloping hills with their buttress-like spurs
are carved out of flat or gently sloping strata, whereas the high, narrow
ridges are carved out of steeply dipping strata.

“The observer’s impression of the scenery will vary with the location
from which he views it. From the river or low river flat he is more
impressed by the high and massive terraces and the steep slopes that front
them than by the actually much bolder relief of the high ridges and the
hills that tower above them. Should he, however, climb the steep ter-
race slope and the yet higher rocky ridges and view, in a different per-
spective, the valley from above, the bold features of the high hills will
dwarf the terraces and flats below. Yet another variation in scenery is
observed away from the main valley. There one is in the midst of the
high steep ridges, the high but gently sloping or flat-topped hills, the long,
steep-sided spurs, and the narrow ravines and gullies.

“Although most of the tributary streams are small, flow in narrow
ravines, and, near their mouths, cut V-shaped notches through the ter-
races of the main valley, a few are larger. Thus Schooler and Carbon
Creeks flow through fairly wide valleys and have long, high terraces,
comparable with those of the main valley.

“Where some of the smaller tributary streams debouch on the low
valley flats they have built up low alluvial fans. The Beattie farm build-
ings [See Plate I B] are erected on such a low, alluvial fan where Aylard
Creek leaves the border of the high terraces on the north side of the valley
and begins its course across Beattie Flat.

“The main valley is broad and deep, and is mostly out of proportion
with the small tributary valleys, except those of Carbon and Schooler

coe It has much the appearance of a great trench across the Foot-
ills.

“Within the Foothills and to the head of Peace River Canyon on the
eastern border. .... Peace River is mostly a smoothly flowing navigable
stream. The only exceptions to this are at Rapide-qui-ne-parle-pas,
Little Parle Pas Rapids, and Black Rock Whirlpool, where projecting
ledges give rise to some bad water. In contrast with the average quiet
flow in the Foothills is the very rough and turbulent water in the canyon,
the upper reaches of which no boat of any kind can navigate. The course
of the river through the rocky walls of the canyon is clearly one of stream
diversion. The river, as it approaches the eastern border of the Foot-
hills, instead of following a previous, and probably preglacial, outlet
through an old gap that now lies between the southern end of the Butler
Ridge and Portage Mountain, and where it could easily have restored its
preglacial course and grade by dissection of the unconsolidated morainal
deposits there, turns abruptly south and southeast (See Plate II A] and
spills over the rocky wall on the south side of the valley. Although this
rock wall has been partly lowered by erosion in the canyon, it still acts as
a dam, and maintains, inside the Foothills, a higher base level than if
the river had flowed through the old gap and restored the preglacial level