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DAVIS: THE PLATEAU PROVINCE OF UTAH AND ARIZONA. 23 
Tue View From Vutcan’s Turone. — The ascent of Vulcan’s throne 
in the late afternoon afforded a much more comprehensive view than 
that of the morning. The ash cone to which a classic name has been 
—somewhat unfortunately — attached is marked on Dutton’s topo- 
graphic map (b, Atlas sheet VIII.) as having an absolute altitude of 
5100 feet: it is therefore about six hundred feet higher than the 
lavas on the esplanade west of the fault in the Uinkaret block, six 
hundred feet higher than the esplanade next east of the fault in the 
Kanab block, and 3500 feet above the river whose channel lies a 
mile south of its summit; but it is 1200 feet below the upland 
of the Kanab plateau block on the northeast. When looking up 
the canyon from the cone, one has the view that has become 
famous in Holmes’s wonderfully effective drawing (Dutton, b, Atlas 
sheet VI.); the esplanade stretching far eastward, enclosed by great 
cliffs and spurs of Aubrey, north and south, and trenched along its 
middle by the inner canyon. Holmes’s graphic interpretation of the 
esplanade floor gives the impression of a greater number of evenly 
graded and waste-covered hills or mounds than I noted in the 
actual view, where the proportion of bare rock is unusually large: the 
softest forms are near the faulted edge of the northern esplanade, 
where a moderate amount of lapilli from Vulcan’s throne cloak the 
surface. 
The northward view shows the broad floor of the Toroweap valley, 
enclosed by promontories of normal Aubrey cliffs along the margin of the 
Kanab plateau on the east, and by Aubrey cliffs cloaked with a marvel- 
lous series of lava cascades from the Uinkaret plateau on the west ; all 
this being portrayed with great fidelity in another of Holmes’s drawings 
(Dutton, b, Atlas sheet V., lower view). This valley is, like its southern 
counterpart, exceptional in following a fault, the other drainage lines of 
the region being as a rule indifferent to faults. Itis however very possible 
that, at the time when the faults occurred in the plateau cycle, drain- 
age lines were instituted consequent upen the slopes of the dislocated 
surface of that time, and that some of the lines followed the depression 
along the junction of each pair of plateau blocks, as has been suggested 
in the account of the Sevier fault at Upper Kanab. In most cases 
these stream lines were broken up as the adjustment of streams to 
structures took place, as in the Pipe spring and Upper Kanab districts ; 
but in the Toroweap district, where the postfault erosion was probably 
concerned for the most part with Permian and lower Trias clays (the 
Shinarump being the only resistant member of this part of the series), 
