156 EXPLORATION OF THE CANONS OF THE COLORADO. 
descending the shaft F. The beds 1-1, 2-2 have been deposited since the 
emergence of the summit of the fold, and hence never extended quite across 
it; yet the lower members of these beds, doubtless, at one time extended 
much farther up on the flanks of the fold. They have been cut away, how 
ever, as represented in the diagram. Let the lines H, H-H, H, represent the 
limit of the continuation of these beds. In the shaft Gr these beds also are 
exposed above those seen in shaft F. 
The altitude of the rocks above the line of observation, (A, B,) is 
exaggerated about five times. If they were reduced to one-fifth, the propor 
tion between the rocks seen in the various escarpments of these mountains, 
and those carried away below the broken lines, would be properly repre 
sented. 
By sinking a shaft, only a little surface along the edge of the strata could 
be seen; but on the sides of the fold they are exposed for many miles, and 
often the top or bottom is cleared off for a great space, revealing even the 
ripple marks of the ancient sea, or rounded impressions of rain drops which 
fell in that elder time; or the sands have buried shells and bones of ancient 
animals, and they are still encased in the rock; and even impressions of 
leaves that were buried in the mud can yet be seen in such a fine state of 
preservation that you can trace their delicate veins. 
In speaking of the great upheaval of rocks from which the Uinta 
Mountains are carved, I have spoken of wrinkling and folding, as if the 
rocks were always flexed; but these displacements are sometimes attended 
with fractures, on one side of which the rocks are upheaved, or thrown down 
on the other. Such displacements are called faults. Faults like these are 
seen in many places in the Uinta Mountains; one great one, on the north 
side, the throw of which is nearly twenty thousand feet, and many others 
are found of lesser magnitude. 
In speaking of elevation and depression by faulting or folding, it must 
be understood that reference is made to a change of altitude in relation to 
the surface of the sea, so that upheaval or throw is only relative to this gen 
eral standard of comparison. But during the geological ages represented 
in the folding and carving of the Uinta Mountains, it is possible the level of 
the sea itself has been changed by the shrinking of the earth, and a part, 
