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_th_, 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_th._—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 _goître_ 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.
[Illustration]
_March_ 19_th._—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.
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.
20_th._—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[1] has
observed the same fact in Spitzbergen. 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[2] than by rain,
and therefore that the appearance of a quicker disintegration of the
solid rock under the snow was deceptive. 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.
[1] Scoresby’s _Arctic Regions_, vol. i, p. 122.
[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 i, 1 p. 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.
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° 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° 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[3] to blow steadily from the
westward or Pacific side. 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 lat. 28°, 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.
[3] Dr. Gillies in _Journ. of Nat. and Geograph. Science_, Aug. 1830.
This author gives the heights of the Passes.
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_nd._—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,[4] which, as
they were high and close together, made it difficult for the cargo
mules to pass. 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.
[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 (_Journ. of Geograph. Soc._ vol. v, p. 12) on the
Neva. Mr. Lyell (_Principles_, vol. iv, p. 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._
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_rd._—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.[5]
[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_th._—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_th._—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_th._—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_th._—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.
30_th._—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_st._—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_th._—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.
Bridge of the Incas—Uspallata Pass
5_th._—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_th._—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.
8_th._—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.
[Illustration: Lima and San Lorenzo]