THE SANTA FE ROUTE, 155 
and it has many caverns where the hot lava has run out at lower 
levels as it congealed at the surface. All the rock is black, practi- 
cally unchanged by weathering, and full of vesicles or small holes, 
due to the escape of steam carried by the molten lava. The edge of 
the sheet is irregular, just as the lava congealed at the margin of the 
flow. At milepost 664 the railway is at the north edge of the lava, 
which it follows for a mile or more to the west, affording an excep- 
tionally interesting and instructive view of the flow and cone. The 
cone, which is near the center of the flow, about 2 miles south of 
milepost 664, is about 200 feet high. It consists of a pile of black 
or dark-gray cinders or pumice, with a large crater in the center. 
In its southwest side there is a deep breach, from which extends a 
thin later sheet of lava that flowed out over the main sheet. This 
accumulation of cinders marks the later stage of the eruption, when 
the vent sputtered out a shower of cinders and fragments of lava 
frothing with steam bubbles. At the same time there were ejected 
pritit'Sand and gravel ..., 
ARE ly nn Trt : 
FIGURE 38.—Ideal ti I gl 1 M vent. 
occasional bombs of more or less completely consolidated lava, which 
are now embedded in the cinder. This volcano and the one at Pisgah, 
43 miles farther west, are exceptionally good examples of a modern 
lava flow, and many features of both are visible from the train. The 
structural relations of flows of this character are shown in figure 38. 
From Amboy to Bagdad the railway line begins to rise gradually 
on the west slope of the basin. 
All trains stop at Bagdad for water and fuel oil. The water is 
brought daily on a train of 20 tank cars filled from springs at New- 
berry, 56 miles to the west. Deep borings at Bag- 
pee: dad and at other points in the basin have obtained 
Elevation 787 feet. only salt water.!_ A short distance north of Bagdad 
KansasCity 1,500miles. - | low ridge which extends far to the northwest. 
It consists of dark massive igneous rock (quartz monzonite), overlain 
by volcanic tuffs and sheets of lava (rhyolite). About 9 miles north 
of.Bagdad are the Marble Mountains, already mentioned. In this 
range is located the Orange Blossom mine (in granite aplite), which 
has yielded copper ore carrying more or less gold. 
1In preserving for the traveler the | inches below the surface, so that they 
water supply of this desert country the | suck up a quantity of water from the soil 
cactus plays an interesting part. The | very quickly after a rain. Once sto 
roots of this distinctly American plant | in its tissues, this water 1s retained by 
extend widely, for the most part at 2 to 4 | the cactus with great tenacity. Water 
