THE MAEBLE CANON. 
203 
relations of the drainage to the structure are so plain and so striking that 
the attention is always arrested by it and the facilities for putting the facts 
together in their normal sequence are unrivaled. 
The Marble Canon platfonn presents but few considerations, and those 
of the most patent kind. Like the Grand Canon platform, it consists of 
Carboniferous strata, with a considerable number of Permian remnants 
scattered over it. The same northward dip of 50 to 100 feet per mile is 
everywhere noticeable, and has the same relative importance, because of 
the great distance over which it prevails. The great feature of the platform 
is, of course, the Marble Canon. Mr. Holmes has given us a sort of bird’s- 
eye view of this chasm, as seen from the lofty heights of the Kaibab. 
(Atlas Sheet No. XIX.) If the Grand Canon were not hard by, and if its 
wholly incomparable magnitudes and grandeur did not belittle everything 
with which we might think of comparing it, the Marble Canon might be 
the theme of some enthusiastic description. Though far inferior to the 
Grand Canon, it surpasses all others in the grandeur and power of those 
features which are the exclusive attributes of canon scenery. 
The Marble Canon begins at the Echo CliflFs. Here the river is almost 
in the open country, its banks being only 200 to 300 feet high. It has just 
emerged from the central mesas of the province through the Glen Canon. 
Turning sharply to the southwest, the river begins at once to burrow into 
the Carboniferous platform. The beds dip almost exactly up stream, so 
that as the river falls, with its onward progress the crests of the walls abso- 
lutely rise. In fact, the progressive deepening of the gorge is due far more 
to the rise of the strata than to the descent of the channel. The declivity 
of the channel is about seven and a half feet per mile, while the rise of the 
strata is nearly eight times as much; and yet it should be borne in mind 
that an inclination of 1° is about equivalent to a slope of 92 feet per mile, 
so that the dip of the beds is really less than 1° — an inclination so small 
that the unaided eye finds ditficulty in recognizing it. But as its effect 
is cumulative it gives to the Marble Canon a depth of rather more than 
3,600 feet at its lower end— a depth which it is very difficult to realize. 
The canon is very simple in form, being a trough with walls, which are 
for the most part neai-ly vertical. The width is about double the depth. 
