ant Wheeler
several times claims the honour of naming it (1868-71), but the name
occurs on Lieutenant Ives's map of 1858. This plateau breaks sharply
along its south-west line to the lowland district, and on its
north-westerly edge slopes to the Little Colorado. It bears a noble pine
forest, and from its summit rise to over 12,000 feet the volcanic peaks
of the San Francisco Mountains. Its northern edge is the Grand Canyon,
which separates it from its kindred on the other side. These and the
Colorado Plateau rise to from 6000 to 8000 feet above sea-level, and
it is through this huge mass that the river has ground out the Grand
Canyon, by corrading its bed down tremendously, the bottom at the end
being only 840 feet above the sea, whereas the start at the mouth of
the Little Colorado is 2690. Yet here it is already 3500 feet below the
surface at the end of Marble Canyon, which, separated only by the deep
canyon of the Little Colorado, is practically a northward continuation
of the Grand Canyon itself. As the river runs, the Grand Canyon is 217
1/2 miles long. To this may be added the 65 1/2 miles of Marble,
giving a continuous chasm of 283 miles, the longest, deepest, and most
difficult of passage in every direction of any canyon in the world. The
depth begins with a couple of hundred feet at Lee's Ferry (mouth of the
Paria), the head of Marble Canyon, and steadily deepens to some 3500
feet near the Little Colorado, where the sudden uplift of the Kaibab
lends about 2000 feet more to the already magnificent gorge. Along the
end of the Kaibab the walls, for a long distance, reach their greatest
height, about 6000 feet, but the other side is considerably lower than
the north all the way through. At the mouth of the Kanab the altitude of
the river-bed is 1800 feet above the sea, showing a fall in the interval
of 890 feet. The greatest declivity is about 210 feet in 10 miles, in
what is termed the Kaibab division, extending from a point 10 miles
below the Little Colorado to a point 58 miles farther down. Here the
smooth stretches of river are long, the rapids short and violent. Here,
also, is the "granite," making the walls sombre, as the colour is slaty
to black. At the mouth of Diamond Creek the river is still 1300 feet
higher than the sea, giving a fall of 500 feet from the Kanab. There is
another descent of 460 feet to the Grand Wash, and then 149 to the mouth
of the Virgen. Next to the Kaibab division of the Grand Canyon,