DENVER & RIO GRANDE WESTERN ROUTE. 193 
The sandstone which rises above water level just below Ruby 
siding is massive—that is, it is almost without bedding planes or 
lines of separation—and consequently it makes a canyon which has 
smooth, nearly vertical walls (Pl. LXXIX). The color, except in 
the uppermost layer, about 100 feet thick, is decidedly red, so that 
in general the canyon walls are a bright red, and the name Ruby is 
quite appropriate. A close look at the sandstone will show that it 
is not evenly banded like many of the sandstones in the region to 
the east, but that the marks along the edges of the beds—which indi- 
cate the form of the layers in which the sand was laid down—dip 
at all angles, or rather are generally curved, showing that the sand 
was carried into the place where it was deposited by strong currents 
of air or water, which cut away much of the sand that had been 
formerly laid down and in its place deposited layer after layer in 
a curved position. This process is termed cross-bedding, and an 
extreme example of it is shown in Plate LXXVI, ( (p. 179). 
These beds were all laid down on the land, or at least no marine 
fossils have been found in them. 
The graceful swing of the river from bend to bend and the corre- 
sponding curves in the smooth massive walls of the canyon are well 
shown in Plate LX XIX. 
he rocks rise gently downstream, and near milepost 477 the 
canyon walls have a height of about 300 feet. Just a little below 
this point dark granite *° appears in the bed of the river, and there- 
fore 300 feet is about the full thickness of the sedimentary beds in 
this canyon. The granite is exposed on the crest of a small anticline 
or uplift, and in a few hundred yards it disappears. The upper sur- 
face of the granite is smooth and doubtless once formed the land 
surface upon which the sand was laid down.” 
granite or gneiss is exposed, and the 
stream has cut its channel in this rock 
to a depth of 1,000 feet. The quartz- 
ites, limestone (Ouray), and variegated 
Carboniferous rocks above the lime- 
stone, extending from the canyon just 
entioned almost as far as Wolcott, 
are not found in Ruby Canyon, As 
many of these formations are of ma- 
" The crystalline rock that censti- 
tutes the foundation upon which west- 
region but that later the sea bottom 
j n canyon of Colorado River 
ust above Glenwood Springs the same 
was uplifted so as to form land and 
then the streams and the weather 
slowly cut the rocks away until in 
places the formations mentioned were 
removed before the red sands were laid 
