116 
THE GEAND CASON DISTEICT. 
nade lies at a much lower level, a.nd the floor of the Queantoweap is a thou- 
sand feet lower. All this arises from the action of the fault, which carries 
down everything to the west of it from 1,200 to 1,^00 feet. From the 
heights of the Uiukaret two great lava cascades descend into the valley, 
each composed of innumerable floods, which are so intimately blended 
together that at a hasty glance they look each like a single mighty outflow. 
The southern cascade emanates from a group of cones, of which Mount Emma 
is the central and dominant pile. The northern cascade, which is wider, but 
probably contains less mass, descends from a line of large craters which 
stand npon the brink of the plateau between the Logan and Emma plat- 
forms. We may descend either of these cascades with ease, but the northern 
one is to be preferred. Reaching the bottom of the Queantoweap, and fol- 
lowing its course downwards until we reach the southern cascade, we turn 
about and, looking northward, observe the features depicted by Mr. Holmes 
in Plate XXII. Three branches of the Hurricane fault are very plainly 
indicated. The high clitf on the right conceals the heights of the Uinkaret 
above and beyond, but by changing our standpoint there is no difficulty in 
recognizing back of this cliff a fonrth branch of the fault, having a displace- 
ment of about 500 feet. Having fixed these dislocations, Ave may now 
return to the lava cascade and ascend to the plateau, noting on our way the 
relations of the lava to the faults. We find that the basalt has not been 
affected by them. The faults were there before the eruptions took place, 
and the lava descending into the valley flowed across them, molding itself 
to whatsoever features the faults and subsequent erosion had generated ; nor 
can Ave detect any trace of shearing in the lava beds. It must be observed, 
however, that the lavas in this cascade are all very yonng, belonging, with- 
out exception, to later eruptions. It is doubtful, even, if they belong to 
those which I have termed middle-aged eruptions, and this term I have 
vised to designate the earlier portions of the more recent outbreaks. They 
are certainly more recent than those which lie north and east of Trumbull. 
Following the branches of the fault north and south, we at length find 
tAvo of them cutting along portions of the Uinkaret flank, where remnants 
of the more ancient lava caps are preserved. Here the faults cut the lavas. 
This is plainly seen on the northwestern flank of Logan and again imme- 
