THE GEANJ3 OAS'ON DISTHHJT. 
US 
of the inner gorge, lising 3,000 feet above us on either hand. Tire river 
now appears more nearly in its true dimensions. Its width varies gi’eatly, 
beiuff from 250 to 450 feet in width. Above and below us are cataracts 
where the water rushes with a deafening roar among huge blocks of basalt, 
and the voice of the waters is reverbei’ated from the faces of the crags in a 
deep solemn monotone that never ceases. Between the cataracts the stream 
outspreads to great width and rushes swiftly by. It is almost always tur- 
bid, and generally is charged with a heavy load of sand and silt. On the 
lowest talus near the brink may be seen lines of high-water mark, some as 
high as fifty or sixt)^ feet above the ordinary summer stages. Within those 
stages the rocks are ground and polished, carved into strange shapes, and 
worn by pot-holes from the scouring of the current. All of the bowlders 
are rounded and ground away, or have become carious and crumbly by the 
chemical reactions of air and water. All things plainly reveal the power- 
ful effects of corrasion acting with extreme energy. We do not wonder at 
it now. The impetuous rush of the waters charged with sharp sand even 
at the lower stages is amply suggestive, and the mind is at a loss to conceive 
what must be the power of the river when its volume is many times multi- 
plied. 
The Toroweap Valley has a significance to the geologist which might 
not be at once apparent to the tourist. Even the geologist would be slow 
to discern it unless familiar with cognate facts displayed in the country at 
large bordering the Grand Canon. In the effort to interpret its meaning it 
becomes necessary to take a hasty view of one or two broad facts relating 
to the lateral drainage of the chasm. Upon the north side there is but one 
side canon carrying drainage from distant regions in all the distance 
between the head of the Marble and the foot of the Grand Canons. This 
single exception is Kanab Canon. In this respect the Colorado is much 
like the lower courses of the Nile ; and the cause is plainl}^ the same. The 
region is too arid to sustain any living streams or even to keep open the 
conduits which in former periods might have sustained them. Yet upon 
the assumption that at some former period the climate was much more humid 
all analogy compels us to believe that the Colorado once received many 
ti’ibutaries which are now extinct, and upon examination we find good evi- 
