THE CRATEES AT THE HEAD OF THE TOROWEAE’. 
83 
wliere the sheets have been undermined and their fragments scattered upon 
tlie plain below. The cones, which stand thick around us, are still in good 
pi’eservation. They are of ordinary composition — mere piles of cinders 
thrown out of central vents and dropping around it. The fume and froth 
of the lava surfaces, the spongy inflated blocks, the lapilli and peperino, 
are not greatly changed, though all of them here show the oxidation of the 
iron. We wonder what their age maybe; what time has elapsed since 
they vomited fire and steam. But there is no clew — no natural record by 
which such events can be calendared. Historically, they have doubtless 
stood in perfect repose for very many centui’ies. Not a trace of activity of 
any kind is visible, and they are as perfectly quiescent as the dead volca- 
noes of the Auvergne or of Scotland. Gleologically, they are extremely 
recent ; yet even here where historic antiquity merges into geologic recency 
the one gives us no measure of the other. 
Following a course which winds among the silent cones and over 
rough, flat surfaces of lava beds half buried in drifting sands, we at 
length reach the border of a slight depression, into which we descend. 
It is hardly noteworthy as a valley just here, and might be confounded 
with any one of the innumerable shallow water courses which occur round 
about; only when we look beyond we see it growing bi'oader and much 
deeper. It is the head of the Toroweap. Upon its smooth bottom is a 
soft clayey soil, in which desert shrubs and stunted sage-brush grow in 
some abundance. Plere and there a cedar, dwarfed indeed, but yet alive, 
displays a welcome green, and upon the valley slopes are a few sprays of 
grass. The valley bottom descends at a noticeable rate to the southward, 
and as we put the miles behind us we find the banks on either side rising 
in height, becoming steeper, and at last displaying rocky ledges. In the 
course of six or seven miles the left side has become a wall 700 feet high, 
while the other side, somewhat lower, is much broken and craggy. Huge 
piles of basalt lie upon the mesa beyond, sheet upon sheet, culminating in 
a cluster of large cones. At length the course of the valley slightly 
deflects to the left, and as we clear a shoulder of the eastern wall, which 
has hitherto masked its continuation, a grand vista breaks upon the sight. 
The valley stretches away to the southward, ever expanding in width; the 
