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Chapter XV
(PLATE 72. HIDE BRIDGE, SANTIAGO DE CHILE.)
Valparaiso.
Portillo Pass.
Sagacity of mules.
Mountain-torrents.
Mines, how discovered.
Proofs of the gradual elevation of the Cordillera.
Effect of snow on rocks.
Geological structure of the two main ranges, their distinct
origin and upheaval.
Great subsidence.
Red snow.
Winds.
Pinnacles of snow.
Dry and clear atmosphere.
Electricity.
Pampas.
Zoology of the opposite sides of the Andes.
Locusts.
Great Bugs.
Mendoza.
Uspallata Pass.
Silicified trees buried as they grew.
Incas Bridge.
Badness of the passes exaggerated.
Cumbre.
Casuchas.
Valparaiso.
PASSAGE OF THE CORDILLERA.
MARCH 7, 1835.
We stayed three days at Concepcion, and then sailed for Valparaiso.
The wind being northerly, we only reached the mouth of the harbour
of Concepcion before it was dark. Being very near the land, and a
fog coming on, the anchor was dropped. Presently a large American
whaler appeared close alongside of us; and we heard the Yankee
swearing at his men to keep quiet, whilst he listened for the
breakers. Captain Fitz Roy hailed him, in a loud clear voice, to
anchor where he then was. The poor man must have thought the voice
came from the shore: such a Babel of cries issued at once from the
ship--every one hallooing out, "Let go the anchor! veer cable!
shorten sail!" It was the most laughable thing I ever heard. If the
ship's crew had been all captains, and no men, there could not have
been a greater uproar of orders. We afterwards found that the mate
stuttered: I suppose all hands were assisting him in giving his
orders.
On the 11th we anchored at Valparaiso, and two days afterwards I
set out to cross the Cordillera. I proceeded to Santiago, where Mr.
Caldcleugh most kindly assisted me in every possible way in making
the little preparations which were necessary. In this part of Chile
there are two passes across the Andes to Mendoza: the one most
commonly used, namely, that of Aconcagua or Uspallata--is situated
some way to the north; the other, called the Portillo, is to the
south, and nearer, but more lofty and dangerous.
MARCH 18, 1835.
(PLATE 73. CHILENOS.)
We set out for the Portillo pass. Leaving Santiago we crossed the
wide burnt-up plain on which that city stands, and in the afternoon
arrived at the Maypu, one of the principal rivers in Chile. The
valley, at the point where it enters the first Cordillera, is
bounded on each side by lofty barren mountains; and although not
broad, it is very fertile. Numerous cottages were surrounded by
vines, and by orchards of apple, nectarine, and peach-trees--their
boughs breaking with the weight of the beautiful ripe fruit. In the
evening we passed the custom-house, where our luggage was examined.
The frontier of Chile is better guarded by the Cordillera than by
the waters of the sea. There are very few valleys which lead to the
central ranges, and the mountains are quite impassable in other
parts by beasts of burden. The custom-house officers were very
civil, which was perhaps partly owing to the passport which the
President of the Republic had given me; but I must express my
admiration at the natural politeness of almost every Chileno. In
this instance, the contrast with the same class of men in most
other countries was strongly marked. I may mention an anecdote with
which I was at the time much pleased: we met near Mendoza a little
and very fat negress, riding astride on a mule. She had a goitre so
enormous that it was scarcely possible to avoid gazing at her for a
moment; but my two companions almost instantly, by way of apology,
made the common salute of the country by taking off their hats.
Where would one of the lower or higher classes in Europe have shown
such feeling politeness to a poor and miserable object of a
degraded race?
At night we slept at a cottage. Our manner of travelling was
delightfully independent. In the inhabited parts we bought a little
firewood, hired pasture for the animals, and bivouacked in the
corner of the same field with them. Carrying an iron pot, we cooked
and ate our supper under a cloudless sky, and knew no trouble. My
companions were Mariano Gonzales, who had formerly accompanied me
in Chile, and an "arriero," with his ten mules and a "madrina." The
madrina (or godmother) is a most important personage: she is an old
steady mare, with a little bell round her neck; and wherever she
goes, the mules, like good children, follow her. The affection of
these animals for their madrinas saves infinite trouble. If several
large troops are turned into one field to graze, in the morning the
muleteers have only to lead the madrinas a little apart, and tinkle
their bells; and although there may be two or three hundred
together, each mule immediately knows the bell of its own madrina,
and comes to her. It is nearly impossible to lose an old mule; for
if detained for several hours by force, she will, by the power of
smell, like a dog, track out her companions, or rather the madrina,
for, according to the muleteer, she is the chief object of
affection. The feeling, however, is not of an individual nature;
for I believe I am right in saying that any animal with a bell will
serve as a madrina. In a troop each animal carries on a level road,
a cargo weighing 416 pounds (more than 29 stone), but in a
mountainous country 100 pounds less; yet with what delicate slim
limbs, without any proportional bulk of muscle, these animals
support so great a burden! The mule always appears to me a most
surprising animal. That a hybrid should possess more reason,
memory, obstinacy, social affection, powers of muscular endurance,
and length of life, than either of its parents, seems to indicate
that art has here outdone nature. Of our ten animals, six were
intended for riding, and four for carrying cargoes, each taking
turn about. We carried a good deal of food in case we should be
snowed up, as the season was rather late for passing the Portillo.
MARCH 19, 1835.
We rode during this day to the last, and therefore most elevated,
house in the valley. The number of inhabitants became scanty; but
wherever water could be brought on the land, it was very fertile.
All the main valleys in the Cordillera are characterised by having,
on both sides, a fringe or terrace of shingle and sand, rudely
stratified, and generally of considerable thickness. These fringes
evidently once extended across the valleys and were united; and the
bottoms of the valleys in northern Chile, where there are no
streams, are thus smoothly filled up. On these fringes the roads
are generally carried, for their surfaces are even, and they rise
with a very gentle slope up the valleys: hence, also, they are
easily cultivated by irrigation. They may be traced up to a height
of between 7000 and 9000 feet, where they become hidden by the
irregular piles of debris. At the lower end or mouths of the
valleys they are continuously united to those land-locked plains
(also formed of shingle) at the foot of the main Cordillera, which
I have described in a former chapter as characteristic of the
scenery of Chile, and which were undoubtedly deposited when the sea
penetrated Chile, as it now does the more southern coasts. No one
fact in the geology of South America interested me more than these
terraces of rudely-stratified shingle. They precisely resemble in
composition the matter which the torrents in each valley would
deposit if they were checked in their course by any cause, such as
entering a lake or arm of the sea; but the torrents, instead of
depositing matter, are now steadily at work wearing away both the
solid rock and these alluvial deposits, along the whole line of
every main valley and side valley. It is impossible here to give
the reasons, but I am convinced that the shingle terraces were
accumulated, during the gradual elevation of the Cordillera, by the
torrents delivering, at successive levels, their detritus on the
beach-heads of long narrow arms of the sea, first high up the
valleys, then lower and lower down as the land slowly rose. If this
be so, and I cannot doubt it, the grand and broken chain of the
Cordillera, instead of having been suddenly thrown up, as was till
lately the universal, and still is the common opinion of
geologists, has been slowly upheaved in mass, in the same gradual
manner as the coasts of the Atlantic and Pacific have risen within
the recent period. A multitude of facts in the structure of the
Cordillera, on this view receive a simple explanation.
(PLATE 74. SOUTH AMERICAN BIT.)
The rivers which flow in these valleys ought rather to be called
mountain-torrents. Their inclination is very great, and their water
the colour of mud. The roar which the Maypu made, as it rushed over
the great rounded fragments, was like that of the sea. Amidst the
din of rushing waters, the noise from the stones, as they rattled
one over another, was most distinctly audible even from a distance.
This rattling noise, night and day, may be heard along the whole
course of the torrent. The sound spoke eloquently to the geologist;
the thousands and thousands of stones which, striking against each
other, made the one dull uniform sound, were all hurrying in one
direction. It was like thinking on time, where the minute that now
glides past is irrevocable. So was it with these stones; the ocean
is their eternity, and each note of that wild music told of one
more step towards their destiny.
It is not possible for the mind to comprehend, except by a slow
process, any effect which is produced by a cause repeated so often
that the multiplier itself conveys an idea not more definite than
the savage implies when he points to the hairs of his head. As
often as I have seen beds of mud, sand, and shingle, accumulated to
the thickness of many thousand feet, I have felt inclined to
exclaim that causes, such as the present rivers and the present
beaches, could never have ground down and produced such masses.
But, on the other hand, when listening to the rattling noise of
these torrents, and calling to mind that whole races of animals
have passed away from the face of the earth, and that during this
whole period, night and day, these stones have gone rattling
onwards in their course, I have thought to myself, can any
mountains, any continent, withstand such waste?
In this part of the valley, the mountains on each side were from
3000 to 6000 or 8000 feet high, with rounded outlines and steep
bare flanks. The general colour of the rock was dullish purple, and
the stratification very distinct. If the scenery was not beautiful,
it was remarkable and grand. We met during the day several herds of
cattle, which men were driving down from the higher valleys in the
Cordillera. This sign of the approaching winter hurried our steps,
more than was convenient for geologising. The house where we slept
was situated at the foot of a mountain, on the summit of which are
the mines of S. Pedro de Nolasko. Sir F. Head marvels how mines
have been discovered in such extraordinary situations, as the bleak
summit of the mountain of S. Pedro de Nolasko. In the first place,
metallic veins in this country are generally harder than the
surrounding strata: hence, during the gradual wear of the hills,
they project above the surface of the ground. Secondly, almost
every labourer, especially in the northern parts of Chile,
understands something about the appearance of ores. In the great
mining provinces of Coquimbo and Copiapó, firewood is very scarce,
and men search for it over every hill and dale; and by this means
nearly all the richest mines have there been discovered.
Chanuncillo, from which silver to the value of many hundred
thousand pounds has been raised in the course of a few years, was
discovered by a man who threw a stone at his loaded donkey, and
thinking that it was very heavy, he picked it up, and found it full
of pure silver: the vein occurred at no great distance, standing up
like a wedge of metal. The miners, also, taking a crowbar with
them, often wander on Sundays over the mountains. In this south
part of Chile the men who drive cattle into the Cordillera, and who
frequent every ravine where there is a little pasture, are the
usual discoverers.
MARCH 20, 1835.
As we ascended the valley, the vegetation, with the exception of a
few pretty alpine flowers, became exceedingly scanty; and of
quadrupeds, birds, or insects, scarcely one could be seen. The
lofty mountains, their summits marked with a few patches of snow,
stood well separated from each other; the valleys being filled up
with an immense thickness of stratified alluvium. The features in
the scenery of the Andes which struck me most, as contrasted with
the other mountain chains with which I am acquainted, were,--the
flat fringes sometimes expanding into narrow plains on each side of
the valleys,--the bright colours, chiefly red and purple, of the
utterly bare and precipitous hills of porphyry, the grand and
continuous wall-like dikes,--the plainly-divided strata which,
where nearly vertical, formed the picturesque and wild central
pinnacles, but where less inclined, composed the great massive
mountains on the outskirts of the range,--and lastly, the smooth
conical piles of fine and brightly coloured detritus, which sloped
up at a high angle from the base of the mountains, sometimes to a
height of more than 2000 feet.
I frequently observed, both in Tierra del Fuego and within the
Andes, that where the rock was covered during the greater part of
the year with snow, it was shivered in a very extraordinary manner
into small angular fragments. Scoresby has observed the same fact
in Spitzbergen. (15/1. Scoresby's "Arctic Regions" volume 1 page
122.) The case appears to me rather obscure: for that part of the
mountain which is protected by a mantle of snow must be less
subject to repeated and great changes of temperature than any other
part. I have sometimes thought that the earth and fragments of
stone on the surface were perhaps less effectually removed by
slowly percolating snow-water than by rain, and therefore that the
appearance of a quicker disintegration of the solid rock under the
snow was deceptive. (15/2. I have heard it remarked in Shropshire
that the water, when the Severn is flooded from long-continued
rain, is much more turbid than when it proceeds from the snow
melting on the Welsh mountains. D'Orbigny tome 1 page 184, in
explaining the cause of the various colours of the rivers in South
America, remarks that those with blue or clear water have their
source in the Cordillera, where the snow melts.) Whatever the cause
may be, the quantity of crumbling stone on the Cordillera is very
great. Occasionally in the spring great masses of this detritus
slide down the mountains, and cover the snow-drifts in the valleys,
thus forming natural ice-houses. We rode over one, the height of
which was far below the limit of perpetual snow.
As the evening drew to a close, we reached a singular basin-like
plain, called the Valle del Yeso. It was covered by a little dry
pasture, and we had the pleasant sight of a herd of cattle amidst
the surrounding rocky deserts. The valley takes its name of Yeso
from a great bed, I should think at least 2000 feet thick, of
white, and in some parts quite pure, gypsum. We slept with a party
of men, who were employed in loading mules with this substance,
which is used in the manufacture of wine. We set out early in the
morning (21st), and continued to follow the course of the river,
which had become very small, till we arrived at the foot of the
ridge that separates the waters flowing into the Pacific and
Atlantic Oceans. The road, which as yet had been good with a steady
but very gradual ascent, now changed into a steep zigzag track up
the great range dividing the republics of Chile and Mendoza.
I will here give a very brief sketch of the geology of the several
parallel lines forming the Cordillera. Of these lines, there are
two considerably higher than the others; namely, on the Chilian
side, the Peuquenes ridge, which, where the road crosses it, is
13,210 feet above the sea; and the Portillo ridge, on the Mendoza
side, which is 14,305 feet. The lower beds of the Peuquenes ridge,
and of the several great lines to the westward of it, are composed
of a vast pile, many thousand feet in thickness, of porphyries
which have flowed as submarine lavas, alternating with angular and
rounded fragments of the same rocks, thrown out of the submarine
craters. These alternating masses are covered in the central parts
by a great thickness of red sandstone, conglomerate, and calcareous
clay-slate, associated with, and passing into, prodigious beds of
gypsum. In these upper beds shells are tolerably frequent; and they
belong to about the period of the lower chalk of Europe. It is an
old story, but not the less wonderful, to hear of shells which were
once crawling on the bottom of the sea, now standing nearly 14,000
feet above its level. The lower beds in this great pile of strata
have been dislocated, baked, crystallised and almost blended
together, through the agency of mountain masses of a peculiar white
soda-granitic rock.
The other main line, namely, that of the Portillo, is of a totally
different formation: it consists chiefly of grand bare pinnacles of
a red potash-granite, which low down on the western flank are
covered by a sandstone, converted by the former heat into a
quartz-rock. On the quartz there rest beds of a conglomerate
several thousand feet in thickness, which have been upheaved by the
red granite, and dip at an angle of 45 degrees towards the
Peuquenes line. I was astonished to find that this conglomerate was
partly composed of pebbles, derived from the rocks, with their
fossil shells, of the Peuquenes range; and partly of red
potash-granite, like that of the Portillo. Hence we must conclude
that both the Peuquenes and Portillo ranges were partially upheaved
and exposed to wear and tear when the conglomerate was forming; but
as the beds of the conglomerate have been thrown off at an angle of
45 degrees by the red Portillo granite (with the underlying
sandstone baked by it), we may feel sure that the greater part of
the injection and upheaval of the already partially formed Portillo
line took place after the accumulation of the conglomerate, and
long after the elevation of the Peuquenes ridge. So that the
Portillo, the loftiest line in this part of the Cordillera, is not
so old as the less lofty line of the Peuquenes. Evidence derived
from an inclined stream of lava at the eastern base of the Portillo
might be adduced to show that it owes part of its great height to
elevations of a still later date. Looking to its earliest origin,
the red granite seems to have been injected on an ancient
pre-existing line of white granite and mica-slate. In most parts,
perhaps in all parts, of the Cordillera, it may be concluded that
each line has been formed by repeated upheavals and injections; and
that the several parallel lines are of different ages. Only thus
can we gain time at all sufficient to explain the truly astonishing
amount of denudation which these great, though comparatively with
most other ranges recent, mountains have suffered.
Finally, the shells in the Peuquenes or oldest ridge prove, as
before remarked, that it has been upraised 14,000 feet since a
Secondary period, which in Europe we are accustomed to consider as
far from ancient; but since these shells lived in a moderately deep
sea, it can be shown that the area now occupied by the Cordillera
must have subsided several thousand feet--in northern Chile as much
as 6000 feet--so as to have allowed that amount of submarine strata
to have been heaped on the bed on which the shells lived. The proof
is the same with that by which it was shown that, at a much later
period since the tertiary shells of Patagonia lived, there must
have been there a subsidence of several hundred feet, as well as an
ensuing elevation. Daily it is forced home on the mind of the
geologist that nothing, not even the wind that blows, is so
unstable as the level of the crust of this earth.
I will make only one other geological remark: although the Portillo
chain is here higher than the Peuquenes, the waters, draining the
intermediate valleys, have burst through it. The same fact, on a
grander scale, has been remarked in the eastern and loftiest line
of the Bolivian Cordillera, through which the rivers pass:
analogous facts have also been observed in other quarters of the
world. On the supposition of the subsequent and gradual elevation
of the Portillo line, this can be understood; for a chain of islets
would at first appear, and, as these were lifted up, the tides
would be always wearing deeper and broader channels between them.
At the present day, even in the most retired Sounds on the coast of
Tierra del Fuego, the currents in the transverse breaks which
connect the longitudinal channels are very strong, so that in one
transverse channel even a small vessel under sail was whirled round
and round.
About noon we began the tedious ascent of the Peuquenes ridge, and
then for the first time experienced some little difficulty in our
respiration. The mules would halt every fifty yards, and after
resting for a few seconds the poor willing animals started of their
own accord again. The short breathing from the rarefied atmosphere
is called by the Chilenos "puna;" and they have most ridiculous
notions concerning its origin. Some say "All the waters here have
puna;" others that "where there is snow there is puna;"--and this
no doubt is true. The only sensation I experienced was a slight
tightness across the head and chest, like that felt on leaving a
warm room and running quickly in frosty weather. There was some
imagination even in this; for upon finding fossil shells on the
highest ridge, I entirely forgot the puna in my delight. Certainly
the exertion of walking was extremely great, and the respiration
became deep and laborious: I am told that in Potosi (about 13,000
feet above the sea) strangers do not become thoroughly accustomed
to the atmosphere for an entire year. The inhabitants all recommend
onions for the puna; as this vegetable has sometimes been given in
Europe for pectoral complaints, it may possibly be of real
service:--for my part I found nothing so good as the fossil shells!
When about half-way up we met a large party with seventy loaded
mules. It was interesting to hear the wild cries of the muleteers,
and to watch the long descending string of the animals; they
appeared so diminutive, there being nothing but the black mountains
with which they could be compared. When near the summit, the wind,
as generally happens, was impetuous and extremely cold. On each
side of the ridge we had to pass over broad bands of perpetual
snow, which were now soon to be covered by a fresh layer. When we
reached the crest and looked backwards, a glorious view was
presented. The atmosphere resplendently clear; the sky an intense
blue; the profound valleys; the wild broken forms: the heaps of
ruins, piled up during the lapse of ages; the bright-coloured
rocks, contrasted with the quiet mountains of snow, all these
together produced a scene no one could have imagined. Neither plant
nor bird, excepting a few condors wheeling around the higher
pinnacles, distracted my attention from the inanimate mass. I felt
glad that I was alone: it was like watching a thunderstorm, or
hearing in full orchestra a chorus of the Messiah.
On several patches of the snow I found the Protococcus nivalis, or
red snow, so well known from the accounts of Arctic navigators. My
attention was called to it by observing the footsteps of the mules
stained a pale red, as if their hoofs had been slightly bloody. I
at first thought that it was owing to dust blown from the
surrounding mountains of red porphyry; for from the magnifying
power of the crystals of snow, the groups of these microscopical
plants appeared like coarse particles. The snow was coloured only
where it had thawed very rapidly, or had been accidentally crushed.
A little rubbed on paper gave it a faint rose tinge mingled with a
little brick-red. I afterwards scraped some off the paper, and
found that it consisted of groups of little spheres in colourless
cases, each the thousandth part of an inch in diameter.
The wind on the crest of the Peuquenes, as just remarked, is
generally impetuous and very cold: it is said to blow steadily from
the westward or Pacific side. (15/3. Dr. Gillies in "Journal of
Natural and Geographical Science" August 1830. This author gives
the heights of the Passes.) As the observations have been chiefly
made in summer, this wind must be an upper and return current. The
Peak of Teneriffe, with a less elevation, and situated in latitude
28 degrees, in like manner falls within an upper return stream. At
first it appears rather surprising that the trade-wind along the
northern parts of Chile and on the coast of Peru should blow in so
very southerly a direction as it does; but when we reflect that the
Cordillera, running in a north and south line, intercepts, like a
great wall, the entire depth of the lower atmospheric current, we
can easily see that the trade-wind must be drawn northward,
following the line of mountains, towards the equatorial regions,
and thus lose part of that easterly movement which it otherwise
would have gained from the earth's rotation. At Mendoza, on the
eastern foot of the Andes, the climate is said to be subject to
long calms, and to frequent though false appearances of gathering
rain-storms: we may imagine that the wind, which coming from the
eastward is thus banked up by the line of mountains, would become
stagnant and irregular in its movements.
Having crossed the Peuquenes, we descended into a mountainous
country, intermediate between the two main ranges, and then took up
our quarters for the night. We were now in the republic of Mendoza.
The elevation was probably not under 11,000 feet, and the
vegetation in consequence exceedingly scanty. The root of a small
scrubby plant served as fuel, but it made a miserable fire, and the
wind was piercingly cold. Being quite tired with my days work, I
made up my bed as quickly as I could, and went to sleep. About
midnight I observed the sky became suddenly clouded: I awakened the
arriero to know if there was any danger of bad weather; but he said
that without thunder and lightning there was no risk of a heavy
snow-storm. The peril is imminent, and the difficulty of subsequent
escape great, to any one overtaken by bad weather between the two
ranges. A certain cave offers the only place of refuge: Mr.
Caldcleugh, who crossed on this same day of the month, was detained
there for some time by a heavy fall of snow. Casuchas, or houses of
refuge, have not been built in this pass as in that of Uspallata,
and therefore, during the autumn, the Portillo is little
frequented. I may here remark that within the main Cordillera rain
never falls, for during the summer the sky is cloudless, and in
winter snow-storms alone occur.
At the place where we slept water necessarily boiled, from the
diminished pressure of the atmosphere, at a lower temperature than
it does in a less lofty country; the case being the converse of
that of a Papin's digester. Hence the potatoes, after remaining for
some hours in the boiling water, were nearly as hard as ever. The
pot was left on the fire all night, and next morning it was boiled
again, but yet the potatoes were not cooked. I found out this by
overhearing my two companions discussing the cause, they had come
to the simple conclusion "that the cursed pot (which was a new one)
did not choose to boil potatoes."
MARCH 22, 1835.
After eating our potato-less breakfast, we travelled across the
intermediate tract to the foot of the Portillo range. In the middle
of summer cattle are brought up here to graze; but they had now all
been removed: even the greater number of the guanacos had decamped,
knowing well that if overtaken here by a snow-storm, they would be
caught in a trap. We had a fine view of a mass of mountains called
Tupungato, the whole clothed with unbroken snow, in the midst of
which there was a blue patch, no doubt a glacier;--a circumstance
of rare occurrence in these mountains. Now commenced a heavy and
long climb, similar to that of the Peuquenes. Bold conical hills of
red granite rose on each hand; in the valleys there were several
broad fields of perpetual snow. These frozen masses, during the
process of thawing, had in some parts been converted into pinnacles
or columns, which, as they were high and close together, made it
difficult for the cargo mules to pass. (15/4. This structure in
frozen snow was long since observed by Scoresby in the icebergs
near Spitzbergen, and, lately, with more care, by Colonel Jackson
"Journal of Geographical Society" volume 5 page 12, on the Neva.
Mr. Lyell "Principles" volume 4 page 360, has compared the
fissures, by which the columnar structure seems to be determined,
to the joints that traverse nearly all rocks, but which are best
seen in the non-stratified masses. I may observe that in the case
of the frozen snow the columnar structure must be owing to a
"metamorphic" action, and not to a process during DEPOSITION.) On
one of these columns of ice a frozen horse was sticking as on a
pedestal, but with its hind legs straight up in the air. The
animal, I suppose, must have fallen with its head downward into a
hole, when the snow was continuous, and afterwards the surrounding
parts must have been removed by the thaw.
When nearly on the crest of the Portillo, we were enveloped in a
falling cloud of minute frozen spicula. This was very unfortunate,
as it continued the whole day, and quite intercepted our view. The
pass takes its name of Portillo from a narrow cleft or doorway on
the highest ridge, through which the road passes. From this point,
on a clear day, those vast plains which uninterruptedly extend to
the Atlantic Ocean can be seen. We descended to the upper limit of
vegetation, and found good quarters for the night under the shelter
of some large fragments of rock. We met here some passengers, who
made anxious inquiries about the state of the road. Shortly after
it was dark the clouds suddenly cleared away, and the effect was
quite magical. The great mountains, bright with the full moon,
seemed impending over us on all sides, as over a deep crevice: one
morning, very early, I witnessed the same striking effect. As soon
as the clouds were dispersed it froze severely; but as there was no
wind, we slept very comfortably.
The increased brilliancy of the moon and stars at this elevation,
owing to the perfect transparency of the atmosphere, was very
remarkable. Travellers having observed the difficulty of judging
heights and distances amidst lofty mountains, have generally
attributed it to the absence of objects of comparison. It appears
to me, that it is fully as much owing to the transparency of the
air confounding objects at different distances, and likewise partly
to the novelty of an unusual degree of fatigue arising from a
little exertion,--habit being thus opposed to the evidence of the
senses. I am sure that this extreme clearness of the air gives a
peculiar character to the landscape, all objects appearing to be
brought nearly into one plane, as in a drawing or panorama. The
transparency is, I presume, owing to the equable and high state of
atmospheric dryness. This dryness was shown by the manner in which
woodwork shrank (as I soon found by the trouble my geological
hammer gave me); by articles of food, such as bread and sugar,
becoming extremely hard; and by the preservation of the skin and
parts of the flesh of the beasts which had perished on the road. To
the same cause we must attribute the singular facility with which
electricity is excited. My flannel-waistcoat, when rubbed in the
dark, appeared as if it had been washed with phosphorus,--every
hair on a dog's back crackled;--even the linen sheets, and leathern
straps of the saddle, when handled, emitted sparks.
MARCH 23, 1835.
The descent on the eastern side of the Cordillera is much shorter
or steeper than on the Pacific side; in other words, the mountains
rise more abruptly from the plains than from the alpine country of
Chile. A level and brilliantly white sea of clouds was stretched
out beneath our feet, shutting out the view of the equally level
Pampas. We soon entered the band of clouds, and did not again
emerge from it that day. About noon, finding pasture for the
animals and bushes for firewood at Los Arenales, we stopped for the
night. This was near the uppermost limit of bushes, and the
elevation, I suppose, was between seven and eight thousand feet.
I was much struck with the marked difference between the vegetation
of these eastern valleys and those on the Chilian side: yet the
climate, as well as the kind of soil, is nearly the same, and the
difference of longitude very trifling. The same remark holds good
with the quadrupeds, and in a lesser degree with the birds and
insects. I may instance the mice, of which I obtained thirteen
species on the shores of the Atlantic, and five on the Pacific, and
not one of them is identical. We must except all those species
which habitually or occasionally frequent elevated mountains; and
certain birds, which range as far south as the Strait of Magellan.
This fact is in perfect accordance with the geological history of
the Andes; for these mountains have existed as a great barrier
since the present races of animals have appeared; and therefore,
unless we suppose the same species to have been created in two
different places, we ought not to expect any closer similarity
between the organic beings on the opposite sides of the Andes than
on the opposite shores of the ocean. In both cases, we must leave
out of the question those kinds which have been able to cross the
barrier, whether of solid rock or salt-water. (15/5. This is merely
an illustration of the admirable laws, first laid down by Mr.
Lyell, on the geographical distribution of animals, as influenced
by geological changes. The whole reasoning, of course, is founded
on the assumption of the immutability of species; otherwise the
difference in the species in the two regions might be considered as
superinduced during a length of time.)
A great number of the plants and animals were absolutely the same
as, or most closely allied to, those of Patagonia. We here have the
agouti, bizcacha, three species of armadillo, the ostrich, certain
kinds of partridges and other birds, none of which are ever seen in
Chile, but are the characteristic animals of the desert plains of
Patagonia. We have likewise many of the same (to the eyes of a
person who is not a botanist) thorny stunted bushes, withered
grass, and dwarf plants. Even the black slowly crawling beetles are
closely similar, and some, I believe, on rigorous examination,
absolutely identical. It had always been to me a subject of regret
that we were unavoidably compelled to give up the ascent of the S.
Cruz river before reaching the mountains: I always had a latent
hope of meeting with some great change in the features of the
country; but I now feel sure that it would only have been following
the plains of Patagonia up a mountainous ascent.
MARCH 24, 1835.
Early in the morning I climbed up a mountain on one side of the
valley, and enjoyed a far extended view over the Pampas. This was a
spectacle to which I had always looked forward with interest, but I
was disappointed: at the first glance it much resembled a distant
view of the ocean, but in the northern parts many irregularities
were soon distinguishable. The most striking feature consisted in
the rivers, which, facing the rising sun, glittered like silver
threads, till lost in the immensity of the distance. At mid-day we
descended the valley, and reached a hovel, where an officer and
three soldiers were posted to examine passports. One of these men
was a thoroughbred Pampas Indian: he was kept much for the same
purpose as a bloodhound, to track out any person who might pass by
secretly, either on foot or horseback. Some years ago a passenger
endeavoured to escape detection by making a long circuit over a
neighbouring mountain; but this Indian, having by chance crossed
his track, followed it for the whole day over dry and very stony
hills, till at last he came on his prey hidden in a gully. We here
heard that the silvery clouds, which we had admired from the bright
region above, had poured down torrents of rain. The valley from
this point gradually opened, and the hills became mere water-worn
hillocks compared to the giants behind; it then expanded into a
gently sloping plain of shingle, covered with low trees and bushes.
This talus, although appearing narrow, must be nearly ten miles
wide before it blends into the apparently dead level Pampas. We
passed the only house in this neighbourhood, the Estancia of
Chaquaio: and at sunset we pulled up in the first snug corner, and
there bivouacked.
MARCH 25, 1835.
I was reminded of the Pampas of Buenos Ayres, by seeing the disk of
the rising sun intersected by an horizon level as that of the
ocean. During the night a heavy dew fell, a circumstance which we
did not experience within the Cordillera. The road proceeded for
some distance due east across a low swamp; then meeting the dry
plain, it turned to the north towards Mendoza. The distance is two
very long days' journey. Our first day's journey was called
fourteen leagues to Estacado, and the second seventeen to Luxan,
near Mendoza. The whole distance is over a level desert plain, with
not more than two or three houses. The sun was exceedingly
powerful, and the ride devoid of all interest. There is very little
water in this "traversia," and in our second day's journey we found
only one little pool. Little water flows from the mountains, and it
soon becomes absorbed by the dry and porous soil; so that, although
we travelled at the distance of only ten or fifteen miles from the
outer range of the Cordillera, we did not cross a single stream. In
many parts the ground was incrusted with a saline efflorescence;
hence we had the same salt-loving plants which are common near
Bahia Blanca. The landscape has a uniform character from the Strait
of Magellan, along the whole eastern coast of Patagonia, to the Rio
Colorado; and it appears that the same kind of country extends
inland from this river, in a sweeping line as far as San Luis, and
perhaps even farther north. To the eastward of this curved line
lies the basin of the comparatively damp and green plains of Buenos
Ayres. The sterile plains of Mendoza and Patagonia consist of a bed
of shingle, worn smooth and accumulated by the waves of the sea;
while the Pampas, covered by thistles, clover, and grass, have been
formed by the ancient estuary mud of the Plata.
After our two days' tedious journey, it was refreshing to see in
the distance the rows of poplars and willows growing round the
village and river of Luxan. Shortly before we arrived at this place
we observed to the south a ragged cloud of a dark reddish-brown
colour. At first we thought that it was smoke from some great fire
on the plains; but we soon found that it was a swarm of locusts.
They were flying northward; and with the aid of a light breeze,
they overtook us at a rate of ten or fifteen miles an hour. The
main body filled the air from a height of twenty feet to that, as
it appeared, of two or three thousand above the ground; "and the
sound of their wings was as the sound of chariots of many horses
running to battle:" or rather, I should say, like a strong breeze
passing through the rigging of a ship. The sky, seen through the
advanced guard, appeared like a mezzotinto engraving, but the main
body was impervious to sight; they were not, however, so thick
together, but that they could escape a stick waved backwards and
forwards. When they alighted, they were more numerous than the
leaves in the field, and the surface became reddish instead of
being green: the swarm having once alighted, the individuals flew
from side to side in all directions. Locusts are not an uncommon
pest in this country: already during this season several smaller
swarms had come up from the south, where, as apparently in all
other parts of the world, they are bred in the deserts. The poor
cottagers in vain attempted by lighting fires, by shouts, and by
waving branches, to avert the attack. This species of locust
closely resembles, and perhaps is identical with, the famous
Gryllus migratorius of the East.
We crossed the Luxan, which is a river of considerable size, though
its course towards the sea-coast is very imperfectly known: it is
even doubtful whether, in passing over the plains, it is not
evaporated and lost. We slept in the village of Luxan, which is a
small place surrounded by gardens, and forms the most southern
cultivated district in the Province of Mendoza; it is five leagues
south of the capital. At night I experienced an attack (for it
deserves no less a name) of the Benchuca, a species of Reduvius,
the great black bug of the Pampas. It is most disgusting to feel
soft wingless insects, about an inch long, crawling over one's
body. Before sucking they are quite thin, but afterwards they
become round and bloated with blood, and in this state are easily
crushed. One which I caught at Iquique (for they are found in Chile
and Peru) was very empty. When placed on a table, and though
surrounded by people, if a finger was presented, the bold insect
would immediately protrude its sucker, make a charge, and if
allowed, draw blood. No pain was caused by the wound. It was
curious to watch its body during the act of sucking, as in less
than ten minutes it changed from being as flat as a wafer to a
globular form. This one feast, for which the benchuca was indebted
to one of the officers, kept it fat during four whole months; but,
after the first fortnight, it was quite ready to have another suck.
MARCH 27, 1835.
We rode on to Mendoza. The country was beautifully cultivated, and
resembled Chile. This neighbourhood is celebrated for its fruit;
and certainly nothing could appear more flourishing than the
vineyards and the orchards of figs, peaches, and olives. We bought
water-melons nearly twice as large as a man's head, most
deliciously cool and well-flavoured, for a halfpenny apiece; and
for the value of threepence, half a wheelbarrowful of peaches. The
cultivated and enclosed part of this province is very small; there
is little more than that which we passed through between Luxan and
the Capital. The land, as in Chile, owes its fertility entirely to
artificial irrigation; and it is really wonderful to observe how
extraordinarily productive a barren traversia is thus rendered.
We stayed the ensuing day in Mendoza. The prosperity of the place
has much declined of late years. The inhabitants say "it is good to
live in, but very bad to grow rich in." The lower orders have the
lounging, reckless manners of the Gauchos of the Pampas; and their
dress, riding-gear, and habits of life, are nearly the same. To my
mind the town had a stupid, forlorn aspect. Neither the boasted
alameda, nor the scenery, is at all comparable with that of
Santiago; but to those who, coming from Buenos Ayres, have just
crossed the unvaried Pampas, the gardens and orchards must appear
delightful. Sir F. Head, speaking of the inhabitants, says, "They
eat their dinners, and it is so very hot, they go to sleep--and
could they do better?" I quite agree with Sir F. Head: the happy
doom of the Mendozinos is to eat, sleep and be idle.
MARCH 29, 1835.
We set out on our return to Chile by the Uspallata pass situated
north of Mendoza. We had to cross a long and most sterile traversia
of fifteen leagues. The soil in parts was absolutely bare, in
others covered by numberless dwarf cacti, armed with formidable
spines, and called by the inhabitants "little lions." There were,
also, a few low bushes. Although the plain is nearly three thousand
feet above the sea, the sun was very powerful; and the heat, as
well as the clouds of impalpable dust, rendered the travelling
extremely irksome. Our course during the day lay nearly parallel to
the Cordillera, but gradually approaching them. Before sunset we
entered one of the wide valleys, or rather bays, which open on the
plain: this soon narrowed into a ravine, where a little higher up
the house of Villa Vicencio is situated. As we had ridden all day
without a drop of water, both our mules and selves were very
thirsty, and we looked out anxiously for the stream which flows
down this valley. It was curious to observe how gradually the water
made its appearance: on the plain the course was quite dry; by
degrees it became a little damper; then puddles of water appeared;
these soon became connected; and at Villa Vicencio there was a nice
little rivulet.
MARCH 30, 1835.
The solitary hovel which bears the imposing name of Villa Vicencio
has been mentioned by every traveller who has crossed the Andes. I
stayed here and at some neighbouring mines during the two
succeeding days. The geology of the surrounding country is very
curious. The Uspallata range is separated from the main Cordillera
by a long narrow plain or basin, like those so often mentioned in
Chile, but higher, being six thousand feet above the sea. This
range has nearly the same geographical position with respect to the
Cordillera, which the gigantic Portillo line has, but it is of a
totally different origin: it consists of various kinds of submarine
lava, alternating with volcanic sandstones and other remarkable
sedimentary deposits; the whole having a very close resemblance to
some of the tertiary beds on the shores of the Pacific. From this
resemblance I expected to find silicified wood, which is generally
characteristic of those formations. I was gratified in a very
extraordinary manner. In the central part of the range, at an
elevation of about seven thousand feet, I observed on a bare slope
some snow-white projecting columns. These were petrified trees,
eleven being silicified, and from thirty to forty converted into
coarsely-crystallised white calcareous spar. They were abruptly
broken off, the upright stumps projecting a few feet above the
ground. The trunks measured from three to five feet each in
circumference. They stood a little way apart from each other, but
the whole formed one group. Mr. Robert Brown has been kind enough
to examine the wood: he says it belongs to the fir tribe, partaking
of the character of the Araucarian family, but with some curious
points of affinity with the yew. The volcanic sandstone in which
the trees were embedded, and from the lower part of which they must
have sprung, had accumulated in successive thin layers around their
trunks; and the stone yet retained the impression of the bark.
It required little geological practice to interpret the marvellous
story which this scene at once unfolded; though I confess I was at
first so much astonished that I could scarcely believe the plainest
evidence. I saw the spot where a cluster of fine trees once waved
their branches on the shores of the Atlantic, when that ocean (now
driven back 700 miles) came to the foot of the Andes. I saw that
they had sprung from a volcanic soil which had been raised above
the level of the sea, and that subsequently this dry land, with its
upright trees, had been let down into the depths of the ocean. In
these depths, the formerly dry land was covered by sedimentary
beds, and these again by enormous streams of submarine lava--one
such mass attaining the thickness of a thousand feet; and these
deluges of molten stone and aqueous deposits five times alternately
had been spread out. The ocean which received such thick masses
must have been profoundly deep; but again the subterranean forces
exerted themselves, and I now beheld the bed of that ocean, forming
a chain of mountains more than seven thousand feet in height. Nor
had those antagonistic forces been dormant, which are always at
work wearing down the surface of the land; the great piles of
strata had been intersected by many wide valleys, and the trees,
now changed into silex, were exposed projecting from the volcanic
soil, now changed into rock, whence formerly, in a green and
budding state, they had raised their lofty heads. Now, all is
utterly irreclaimable and desert; even the lichen cannot adhere to
the stony casts of former trees. Vast, and scarcely comprehensible
as such changes must ever appear, yet they have all occurred within
a period, recent when compared with the history of the Cordillera;
and the Cordillera itself is absolutely modern as compared with
many of the fossiliferous strata of Europe and America.
APRIL 1, 1835.
We crossed the Uspallata range, and at night slept at the
custom-house--the only inhabited spot on the plain. Shortly before
leaving the mountains, there was a very extraordinary view; red,
purple, green, and quite white sedimentary rocks, alternating with
black lavas, were broken up and thrown into all kinds of disorder
by masses of porphyry of every shade of colour, from dark brown to
the brightest lilac. It was the first view I ever saw, which really
resembled those pretty sections which geologists make of the inside
of the earth.
The next day we crossed the plain, and followed the course of the
same great mountain stream which flows by Luxan. Here it was a
furious torrent, quite impassable, and appeared larger than in the
low country, as was the case with the rivulet of Villa Vicencio. On
the evening of the succeeding day we reached the Rio de las Vacas,
which is considered the worst stream in the Cordillera to cross. As
all these rivers have a rapid and short course, and are formed by
the melting of the snow, the hour of the day makes a considerable
difference in their volume. In the evening the stream is muddy and
full, but about daybreak it becomes clearer and much less
impetuous. This we found to be the case with the Rio Vacas, and in
the morning we crossed it with little difficulty.
The scenery thus far was very uninteresting, compared with that of
the Portillo pass. Little can be seen beyond the bare walls of the
one grand, flat-bottomed valley, which the road follows up to the
highest crest. The valley and the huge rocky mountains are
extremely barren: during the two previous nights the poor mules had
absolutely nothing to eat, for excepting a few low resinous bushes,
scarcely a plant can be seen. In the course of this day we crossed
some of the worst passes in the Cordillera, but their danger has
been much exaggerated. I was told that if I attempted to pass on
foot, my head would turn giddy, and that there was no room to
dismount; but I did not see a place where any one might not have
walked over backwards, or got off his mule on either side. One of
the bad passes, called las Animas (the Souls), I had crossed, and
did not find out till a day afterwards that it was one of the awful
dangers. No doubt there are many parts in which, if the mule should
stumble, the rider would be hurled down a great precipice; but of
this there is little chance. I daresay, in the spring, the
"laderas," or roads, which each year are formed anew across the
piles of fallen detritus, are very bad; but from what I saw, I
suspect the real danger is nothing. With cargo-mules the case is
rather different, for the loads project so far, that the animals,
occasionally running against each other, or against a point of
rock, lose their balance, and are thrown down the precipices. In
crossing the rivers I can well believe that the difficulty may be
very great: at this season there was little trouble, but in the
summer they must be very hazardous. I can quite imagine, as Sir F.
Head describes, the different expressions of those who HAVE passed
the gulf, and those who ARE passing. I never heard of any man being
drowned, but with loaded mules it frequently happens. The arriero
tells you to show your mule the best line, and then allow her to
cross as she likes: the cargo-mule takes a bad line, and is often
lost.
APRIL 4, 1835.
From the Rio de las Vacas to the Puente del Incas, half a day's
journey. As there was pasture for the mules, and geology for me, we
bivouacked here for the night. When one hears of a natural Bridge,
one pictures to oneself some deep and narrow ravine, across which a
bold mass of rock has fallen; or a great arch hollowed out like the
vault of a cavern. Instead of this, the Incas Bridge consists of a
crust of stratified shingle cemented together by the deposits of
the neighbouring hot springs. It appears as if the stream had
scooped out a channel on one side, leaving an overhanging ledge,
which was met by earth and stones falling down from the opposite
cliff. Certainly an oblique junction, as would happen in such a
case, was very distinct on one side. The Bridge of the Incas is by
no means worthy of the great monarchs whose name it bears.
APRIL 5, 1835.
We had a long day's ride across the central ridge, from the Incas
Bridge to the Ojos del Agua, which are situated near the lowest
casucha on the Chilian side. These casuchas are round little
towers, with steps outside to reach the floor, which is raised some
feet above the ground on account of the snow-drifts. They are eight
in number, and under the Spanish government were kept during the
winter well stored with food and charcoal, and each courier had a
master-key. Now they only answer the purpose of caves, or rather
dungeons. Seated on some little eminence, they are not, however,
ill suited to the surrounding scene of desolation. The zigzag
ascent of the Cumbre, or the partition of the waters, was very
steep and tedious; its height, according to Mr. Pentland, is 12,454
feet. The road did not pass over any perpetual snow, although there
were patches of it on both hands. The wind on the summit was
exceedingly cold, but it was impossible not to stop for a few
minutes to admire, again and again, the colour of the heavens, and
the brilliant transparency of the atmosphere. The scenery was
grand: to the westward there was a fine chaos of mountains, divided
by profound ravines. Some snow generally falls before this period
of the season, and it has even happened that the Cordillera have
been finally closed by this time. But we were most fortunate. The
sky, by night and by day, was cloudless, excepting a few round
little masses of vapour, that floated over the highest pinnacles. I
have often seen these islets in the sky, marking the position of
the Cordillera, when the far-distant mountains have been hidden
beneath the horizon.
APRIL 6, 1835.
In the morning we found some thief had stolen one of our mules, and
the bell of the madrina. We therefore rode only two or three miles
down the valley, and stayed there the ensuing day in hopes of
recovering the mule, which the arriero thought had been hidden in
some ravine. The scenery in this part had assumed a Chilian
character: the lower sides of the mountains, dotted over with the
pale evergreen Quillay tree, and with the great chandelier-like
cactus, are certainly more to be admired than the bare eastern
valleys; but I cannot quite agree with the admiration expressed by
some travellers. The extreme pleasure, I suspect, is chiefly owing
to the prospect of a good fire and of a good supper, after escaping
from the cold regions above: and I am sure I most heartily
participated in these feelings.
APRIL 8, 1835.
We left the valley of the Aconcagua, by which we had descended, and
reached in the evening a cottage near the Villa de St. Rosa. The
fertility of the plain was delightful: the autumn being advanced,
the leaves of many of the fruit-trees were falling; and of the
labourers,--some were busy in drying figs and peaches on the roofs
of their cottages, while others were gathering the grapes from the
vineyards. It was a pretty scene; but I missed that pensive
stillness which makes the autumn in England indeed the evening of
the year. On the 10th we reached Santiago, where I received a very
kind and hospitable reception from Mr. Caldcleugh. My excursion
only cost me twenty-four days, and never did I more deeply enjoy an
equal space of time. A few days afterwards I returned to Mr.
Corfield's house at Valparaiso.
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