John Charles Van Dyke.

The desert; further studies in natural appearances online

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of things. You hear no clash or crash or snarl.
The desert is overwhelmingly silent. There
is not a sound to be heard ; and not a thing
moves save the wind and the sands. But you
look up at the worn peaks and the jagged bar-
rancas, you look down at the wash-outs and
piled bowlders, you look about at the wind-
tossed, half -starved bushes ; and, for all the
silence, you know that there is a struggle for
life, a war for place, going on day by day.

How is it possible under such conditions for
much vegetation to flourish ? The grasses are
scanty, the grease wood and cactus grow in
patches, the mesquite crops out only along the



The inces-
sant
struggle.



Elemental
warfare.



Desert
vegetation.



28



THE DESERT



Protruding



Shifting
sands.



dry river-beds. All told there is hardly enough
covering to hide the anatomy of the earth.
And the winds are always blowing it aside.
You have noticed how bare and bony the hills
of New England are in winter when the trees
are leafless and the grasses are dead ? You have
seen the rocks loom up harsh and sharp, the
ledges assume angles, and the backbone and ribs
of the open field crop out of the soil ? The
desert is not unlike that all the year round.
To be sure there are snow-like drif tings of sand
that muffle certain edges. Valleys, hills, and
even mountains are turned into rounded lines
by it at times. But the drift rolled high in
one place was cut out from some other place ;
and always there are vertebrce showing elbows
and shoulders protruding through the yellow
byssus of sand.

The shifting sands ! Slowly they move, wave
upon wave, drift upon drift ; but by day and
by night they gather, gather, gather. They
overwhelm, they bury, they destroy, and then
a spirit of restlessness seizes them and they
move off elsewhere, swirl upon swirl, line upon
line, in serpentine windings that enfold some
new growth or fill in some new valley in the
waste. So it happens that the surface of the



THE MAKE OF THE DESERT



desert is far from being a permanent affair.
There is hardly enough vegetation to hold the
sands in place. With little or no restraint upon
them they are transported hither and yon at
the mercy of the winds.

Yet the desert winds hardly blow where they
list. They follow certain channels or " draws "
through the mountain ranges ; and the reason
for their doing so is plain enough. During the
day the intense heat of the desert, meeting with
only a thin dry air above it, rises rapidly sky-
ward leaving a vast vacuum below that must be
filled with a colder air from without. This
colder air on the southern portion of the Colo-
rado Desert comes in from the Gulf region.
One can feel it in the passes of the mountains
about Baboquivari, rushing up toward the
heated portions of Arizona around Tucson.
And the hotter the day the stronger the inward
rush of the wind. Some days it will blow at
the rate of fifty miles an hour until sunset, and
then with a cessation of radiation the wind
stops and the night is still.

On the western portions of the Colorado the
wind comes from the Pacific across Southern
California. The hot air from the desert goes
up and out over the Coast Range, reaching sea-



Desert
winds.



Radiation
of heat.



30



THE DESEET



Prevailing
winds.



Wear of
the winds.



ward. How far out it goes is unknown, but
when it has cooled off it descends and flows
back toward the land as the daily sea-breeze.
It re-enters the desert through such loop holes
in the Coast Eange as the San Gorgonio Pass
the old Puerta de San Carlos above Indio.
The rush of it through that pass is quite vio-
lent at times. For wind is very much like
water and seeks the least obstructed way. Its
goal is usually the hottest and the lowest place
on the desert such a place, for example, as
Salton, though I am not prepared to point out
the exact spot on the desert that the winds
choose as a target. On the Mojave Desert at
the north their action is similar, though there
they draw down from the Mount Whitney re-
gion as well as from the Pacific.

In open places these desert winds are some-
times terrific in force though usually they are
moderate and blow with steadiness from certain
directions. As you feel them softly blowing
against your cheek it is hard to imagine that they
have any sharp edge to them. Yet about you
on every side is abundant evidence of their
works. The sculptor's sand-blast works swifter
but not surer. Granite and porphyry cannot
withstand them, and in time they even cut



THE MAKE OF THE DESERT



31



through the glassy surface of lava. Their wear
is not here nor there, but all over, everywhere.
The edge of the wind is always against the stone.
Continually there is the slow erosion of canyon,
crag, and peak ; forever there is a gnawing at
the bases and along the face- walls of the great
sierras. Grain by grain, the vast foundations,
the beetling escarpments, the high domes in air
are crumbled away and drifted into the valleys.
Nature heaved up these mountains at one time
to fulfil a purpose : she is now taking them
down to fulfil another purpose. If she has
not water to work with here as elsewhere she is
not baffled of her purpose. Wind and sand an-
swer quite as well.

But the cutting of the wind is not always
even or uniform, owing to the inequalities in
the fibre of rock ; and often odd effects are pro-
duced by the softer pieces of rock wearing away
first and leaving the harder section exposed to
view. Frequently these remainders take on
fantastic shapes and are likened to things hu-
man, such as faces, heads, and hands. In the
San Gorgonio Pass the rock-cuttings are in
parallel lines, and occasionally a row of gar-
nets in the rock will make the jewel-pointed
fingers of a hand protruding from the parent



Erosion of
mountains.



Rock-
cutting.



THE DESERT



Fantastic
forms.



Wash-outs.



Sand-lines
in caves.



body.* Again shafts of hard granite may make
tall spires and turrets npon a mountain peak, a
vein of quartz may bulge out in a white or yel-
low or rose-colored band ; and a ridge of black
lava, reaching down the side of a foot-hill, may
creep and heave like the backbone of an enor-
mous dragon.

Perhaps the greatest erosion is in the passes
through which the winds rush into the desert.
Here they not only eat into the ledges and cut
away the rock faces, but they make great wash-
outs in the desert itself. These trenches look
in every respect as though caused by water. In
fact the effects of wind and water are often so
inextricably mixed that not even an expert geol-
ogist would be able to say where the one leaves
off and the other begins. The shallow caves of
the mountains too high up for any wave action
from sea or lake, and too deep to be reached
by rains have all the rounded appearance of
water-worn receptacles. One can almost see
the water-lines upon the walls. Bnt the sand-
heaped floor suggests that the agent of erosion
was the wind.

Yes ; there is some water on the deserts, some

* Professor Blake of the University of Arizona has
palled my attention to tliia,



THE MAKE OF THE DESEET



33



rainfall each year. Even Sahara gets its occa-
sional showers, and the Colorado and the Mo-
jave show many traces of the cloud-burst. The
dark thunder-clouds that occasionally gather
over the desert seem at times to reserve all their
stores of rain for one place. The fall is usually
short-lived but violent ; and its greatest force
is always on the mountains. There is no sod,
no moss, to check or retard the flood ; and the
result is a great rush of water to the low places.
In the canyons the swollen streams roll down
bowlders that weigh tons, and in the ravines
many a huge barranca is formed in a single
hour by these rushing waters. On the lomas
and sloping valleys they are not less destructive,
running in swift streams down the hollows, and
whirling stones, sand, and torn bushes into the
old river-beds.

In a very short time there is a great torrent
pouring down the valley a torrent composed
of water, sand, and gravel in about equal parts.
It is a yellow, thick stream that has nothing but
disaster for the man or beast that seeks to swim
it. Many a life has been lost there. The great
onset of the water destroys anything like buoy-
ancy, and the tendency is to drag down and
roll the swimmer like a bowlder. Even the



Cloud-
bursts.



Canyon
streams.



floods.



34



THE DESERT



JVb running
streams.



enormous strength of the grizzly bear has been
known to fail him in these desert rivers. They
boil and seethe as though they were hot ; and
they rush on against banks, ripping out the
long roots of mesquite, and swirling away tons
of undermined gravel as though it were only so
much snow. At last after miles of this mill-
racing the force begins to diminish, the streams
reach the flat lake-beds and spread into broad,
thin sheets ; and soon they have totally van-
ished, leaving scarce a rack behind.

The desert rainfall comes quickly and goes
quickly. The sands drink it up, and it sinks
to the rock strata, where, following the ledges, it
is finally shelved into some gravel-bed. There,
perhaps a hundred feet under the sand, it slow-
ly oozes away to the river or the Gulf. There
is none of it remains upon the surface except
perhaps a pool caugKt in a clay basin, or a
catch of water in a rocky bowl of some canyon.
Occasionally one meets with a little stream
where a fissure in the rock and a pressure from
below forces up some of the water ; but these
springs are of very rare occurrence. And they
always seem a little strange. A brook that ran
on the top of the ground would be an anomaly
here ; and after one lives many months on the



THE MAKE OF THE DESERT



35



desert and returns to a well- watered country,
the last thing he becomes accustomed to is the
sight of running water.

In every desert there are isolated places
where water stands in pools, fed by under-
ground springs, where mesquite and palms
grow, and where there is a show of coarse
grass over some acres. These are the so-called
oases in the waste that travellers have pictured
as Gardens of Paradise, and poets have used
for centuries as illustrations of happiness sur-
rounded by despair. To tell the truth they
are wretched little mud-holes ; and yet because
of their few trees and their pockets of yellow
brackish water they have an appearance of un-
reality. They are strange because bright-green
foliage and moisture of any kind seem out of
place on the desert.

Yet surely there was plenty of water here at
one time. Everywhere you meet with the dry
lake-bed its flat surface devoid of life and of-
ten glimmering white with salt. These beds
are no doubt of recent origin geologically, and
were never more than the catch-basins of sur-
face water; but long before ever they were
brought forth the whole area of the desert
was under the sea. To-day one may find on



Oases in the
waste.



Catch-
basins.



36



THE DESEKT



the high table-lands sea-shells in abundance.
The petrified clams are precisely like the live
clams that one picks np on the western coast
of Mexico. The corals, barnacles, dried sponge
forms, and cellular rocks do not differ from
those in the Gulf of California. The change
from sea to shore, and from shore to table-land
and mountain, no doubt took place very slow-
ly. Just how many centuries ago who shall
say ? Geologists may guess and laymen may
doubt, but the Keeper of the Seals says noth-
ing.

Nor is it known just when the porphyry
mountains were roasted to a dark wine-red,
and the foot-hills burnt to a terra-cotta orange.
Fire has been at work here as well as wind
and water. The whole country has a burnt
and scorched look proceeding from something
more fiery than sunlight. Volcanoes have left
their traces everywhere. You can still see the
streams of lava that have chilled as they ran.
The blackened cones with their craters exist ;
and about them, for many miles, there are
great lakes and streams of reddish-black lava,
frozen in swirls and pools, cracked like glass,
broken into blocks like a ruined pavement.
Wherever you go on the desert you meet with



THE MAKE OF THE DESERT



37



chips and breaks of lava, showing that at one
time there must have been quantities of it
belched out of the volcanoes.

There were convulsions in those days when
the sea washed close to the bases of the moun-
tains. Through the crevasses and fissures in the
rocks the water crept into the fires of the earth,
and explosions volcanic eruptions were the
result. Wandering over these stony tracks you
might fancy that all strata and all geological
ages were blown into discord by those explo-
sions. For here are many kinds of splintered
and twisted rocks rocks aqueous and igne-
ous, gritstones, conglomerates, shales, slates,
syenite, basalt. And everywhere the white
coatings of carbonate of lime that look as
though they were run hot from a puddling fur-
nace ; and the dust of sulphur, copper, and
iron blown upon granite as though oxidized by
fire.

The evidence for glaciers is not so convinc-
ing. There is no apparent sign of an ice age.
Occasionally one sees scratches upon mountain
walls that are suspicious, or heaps of sand and
gravel that look as though pushed into the
small valleys by some huge force. And again
there are places on the Mojave where windrows



Geological
ages.



Kinds of
rock.



Glaciers.



38



THE DESERT



Land slips.



Movement
of stones.



The talus.



of heavy bowlders are piled on either side of
mountain water-courses, looking as though ice
may have caused their peculiar placing. But
there is no certainty about any of these. Land
slips may have made the windrows as easily as
ice slips ; and water can heap mounds of sand
and gravel as readily as glaciers. One cannot
trace the geological ages with such facility.
Things sometimes " just happen," in spite of
scientific theories.

Besides, the movement of the stones into the
valleys is going on continuously, irrespective of
glaciers. They are first broken from the peaks
by erosion, and then they fall into what is called
a talus a great slope of stone blocks beginning
half way down the mountain and often reaching
to the base or foot. Many of them, of course,
are rolled over steep declivities into the canyons
and thence carried down by flood waters ; but
the talus is the more uniform method for bowl-
ders reaching the plain.

In the first stage of the talus the blocks are
ragged-edged and as large as a barrel. Nothing
whatever grows upon the slope. It is as bare as
the side of a volcanic crater. And just as diffi-
cult to walk over. The talus is added to at the
top by the falling rock of the face-wall, and it



THE MAKE OF THE DESERT



39



is losing at the bottom by the under blocks
grinding away to stone and gravel. The flat-
tening out at the bottom, the breaking up of
the blocks, and the push-out of the mountain
foot upon the plain is the second stage of the
talus. In almost all the large valleys of the
desert the depressed talus extends, sometimes
miles in length, out from the foot of the moun-
tain range. When it finally slips down into the
valley and becomes a flat floor it has entered
upon its third and last stage. It is then the
ordinary valley-bed covered with its cactus and
cut by its arroyos. Yet this valley-floor instead
of being just one thing is really many things
or rather made up of many different materials
and showing many different surfaces.

You may spend days and weeks studying the
make-up of these desert-floors. Beyond Yuma
on the Colorado there are thousands of acres of
mosaic pavement, made from tiny blocks of
jasper, carnelian, agate a pavement of pebbles
so hard that a horse's hoof will make no im-
pression upon it wind-swept, clean, compact
as though pressed down by a roller. One can
imagine it made by the winds that have cut
and drifted away the light sands and allowed
the pebbles to settle close together until they



Stages of
the talus.



Desert-
floors.



40



THE DESERT



Sandstone
blocks.



Saltbeds.



Sand-beds.



have become wedged in a solid surface. For no
known reason other portions of the desert are
covered with blocks of red-incrusted sandstone
the incrustation being only above the sand-
line. In the lake-beds there is usually a surface
of fine silt. It is not a hard surface though it
often has a crust upon it that a wildcat can
walk upon, but a horse or a man would pound
through as easily as through crusted snow.
The salt-beds are of sporadic appearance and
hardly count as normal features of the desert.
They are often quite beautiful in appearance.
The one on the Colorado near Salton is hard as
ice, white, and after sunset it often turns blue,
yellow, or crimson, dependent upon the sky
overhead which it reflects. Borax and gypsum-
beds are even scarcer than the salt-beds. They
are also white and often very brilliant reflectors
of the sky. The sand-beds are, of course, more
frequently met with than any others ; and yet
your horse does not go knee-deep in sand for
any great distance. It is too light, and is
drifted too easily by the winds. Bowlders,
gravel, and general mountain wash is the most
common flooring of all.

The mountains whence all the wash comes,
are mere ranges of rock. In the canyons, where



THE MAKE OF THE DESERT



41



there is perhaps some underground water, there
are occasionally found trees and large bushes,
and the very high sierras have forests of pine
belted about their tops ; but usually the desert
ranges are barren. They never bore fruit. The
washings from them are grit and fry of rock
but no vegetable mould. The black dirt that
lies a foot or more in depth upon the surface of
the eastern prairies, showing the many years
accumulations of decayed grasses and weeds, is
not known anywhere on the desert. The slight
vegetation that grows never has a chance to turn
into mould. And besides, nothing ever rots or
decays in these sands. Iron will not rust, nor
tin tarnish, nor flesh mortify. The grass and
the shrub wither and are finally cut into pieces
by flying sands. Sometimes you may see small
particles of grass or twigs heaped about an ant-
hill, or find them a part of a bird's nest in a
cholla ; but usually they turn to dry dust and
blow with the wind at the wind's will.

The desert mountains gathered in clusters
along the waste, how old and wrinkled, how set
and determined they look ! Somehow they
remind you of a clinched hand with the
knuckles turned skyward. They have strength
and bulk, the suggestion of quiescent force.



Mountain
vegetation.



Withered
grasses.



42



THE DESERT



Barren
rock.



Mountain
colors.



Saw-toothed
ridges.



Barren rock and nothing more ; but what could
better epitomize power ! The heave of the
enormous ridge, the loom of the domed top,
the bulk and body of the whole are colossal.
Rising as they do from flat sands they give the
impression of things deep-based veritable isl-
ands of porphyry bent upward from a yellow
sea. They are so weather-stained, so worn,
that they are not bright in coloring. Usually
they assume a dull garnet-red, or the red of
peroxide of iron ; but occasionally at sunset
they warm in color and look fire-red through
the pink haze.

The more abrupt ranges that appear younger
because of their saw-toothed ridges and broken
peaks, are often much finer in coloring. They
have needles that are lifted skyward like Mos-
lem minarets or cathedral spires ; and at even-
ing, if there is a yellow light, they shine like
brazen spear-points set against the sky. It is
astonishing that dull rock can disclose such
marvellous coloring. The coloring is not local
in the rock, nor yet again entirely reflected.
Desert atmosphere, with which we shall have to
reckon hereafter, has much to do with it.

And whether at sunset, at sunrise, or at mid-
night, how like watch-towers these mountains



THE MAKE OF THE DESEKT



43



stand above the waste ! One can almost fancy
that behind each dome and rampart there are
clond-like Genii spirits of the desert keeping
guard over this kingdom of the snn. And what
a far-reaching kingdom they watch ! Plain npon
plain leads up and out to the horizon far as the
eye can see in undulations of gray and gold ;
ridge upon ridge melts into the blue of the
distant sky in lines of lilac and purple ; fold
upon fold over the mesas the hot air drops its
veilings of opal and topaz. Yes ; it is the
kingdom of sun-fire. For every color in the
scale is attuned to the key of flame, every air-
wave comes with the breath of flame, every
sunbeam falls as a shaft of flame. There is
no questioning who is sovereign in these do-
minions.



Seen from
the peaks.



Sun-fire
kingdom.



CHAPTEE III



Early

geological

days.



The former
Gulf.



THE BOTTOM OF THE BOWL

IN the ancient days when the shore of the
Pacific was young, when the white sierras had
only recently been heaved upward and the des-
ert itself was in a formative stage, the ocean
reached much farther inland than at the pres-
ent time. It pushed through many a pass and
flooded many a depression in the sands, as its
wave-marks upon granite bases and its numer-
ous beaches still bear witness. In those days
that portion of the Colorado Desert known as
the Salton Basin did not exist. The Gulf of
California extended as far north as the San
Bernardino Eange and as far west as the Pass
of San Gorgonio. Its waters stood deep where
now lies the road-bed of the Southern Pacific
railway, and all the country from Indio almost
to the Colorado Eiver was a blue sea. The
Bowl was full. No one knew if it had a bot-
tom or imagined that it would ever be emptied
of water and given over to the drifting sands.
44



THE BOTTOM OF THE BOWL



No doubt the tenure of the sea in this Salton
Basin was of long duration. The sand-dunes
still standing along the northern shore fifty
feet high and shining like hills of chalk
were not made in a month ; nor was the long
shelving beach beneath them still covered
with sea-shells and pebbles and looking as
though washed by the waves only yesterday
formed in a day. Both dunes and beach are
plainly visible winding across the desert for
many miles. The southwestern shore, stretch-
ing under a spur of the Coast Kange, shows the
same formation in its beach -line. The old
bays and lagoons that led inland from the sea,
the river-beds that brought down the surface
waters from the mountains, the inlets and nat-
ural harbors are all in place. Some of them
are drifted half full of sand, but they have not
lost their identity. And out in the sea-bed
still stand masses of cellular rock, honeycombed
and water- worn (and now for many years wind-
worn), showing the places where once rose the
reefs of the ancient sea.

These are the only records that tell of the
sea's occupation. The Indians have no tra-
dition about it. Yet when the sea was there
the Indian tribes were there also. Along the



Sea-beaches
on desert.



Harbors
and reef*.



46



THE DESERT



Indian
remains.



The
Cocopas.



The

Colorado

Eiver.



bases of the San Bernardino and San Jacinto
Ranges there are indications of cave-dwelling,
rock-built squares that doubtless were fortified
camps, heaps of stone that might have been
burial-mounds. Everywhere along the ancient
shores and beaches you pick up pieces of pot-
tery, broken ollas, stone pestels and mortars,
axe - heads, obsidian arrow - heads, flint spear-
points, agate beads. There is not the slightest
doubt that the shores were inhabited. It was
a warm nook, accessible to the mountains and
the Pacific; in fact, just the place where
tribes would naturally gather. Branches of
the Yuma Indians, like the Cocopas, overran
all this country when the Padres first crossed
the desert ; and it was probably their fore-
fathers who lived by the shores of this Upper
Gulf. No doubt they were fishermen, traders
and fighters, like their modern representatives
on Tiburon Island ; and no doubt they fished
and fought and were happy by the shores of
the mountain-locked sea.

But there came a time when there was a dis-
turbance of the existing conditions in the Up-
per Gulf. Century after century the Colorado
River had been carrying down to the sea its
burden of sedimental sand and silt. It had



THE BOTTOM OF THE BOWL



47



been entering the Gulf far down on the eastern
side at an acute angle. Gradually its deposits


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