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appears absolutely level; so that when at Lima it is difficult to
believe one has ascended even one hundred feet: Humboldt has
remarked on this singularly deceptive case. Steep barren hills rise
like islands from the plain, which is divided, by straight
mud-walls, into large green fields. In these scarcely a tree grows
excepting a few willows, and an occasional clump of bananas and of
oranges. The city of Lima is now in a wretched state of decay: the
streets are nearly unpaved; and heaps of filth are piled up in all
directions, where the black gallinazos, tame as poultry, pick up
bits of carrion. The houses have generally an upper story, built,
on account of the earthquakes, of plastered woodwork; but some of
the old ones, which are now used by several families, are immensely
large, and would rival in suites of apartments the most magnificent
in any place. Lima, the City of the Kings, must formerly have been
a splendid town. The extraordinary number of churches gives it,
even at the present day, a peculiar and striking character,
especially when viewed from a short distance.

One day I went out with some merchants to hunt in the immediate
vicinity of the city. Our sport was very poor; but I had an
opportunity of seeing the ruins of one of the ancient Indian
villages, with its mound like a natural hill in the centre. The
remains of houses, enclosures, irrigating streams, and burial
mounds, scattered over this plain, cannot fail to give one a high
idea of the condition and number of the ancient population. When
their earthenware, woollen clothes, utensils of elegant forms cut
out of the hardest rocks, tools of copper, ornaments of precious
stones, palaces, and hydraulic works, are considered, it is
impossible not to respect the considerable advance made by them in
the arts of civilisation. The burial mounds, called Huacas, are
really stupendous; although in some places they appear to be
natural hills encased and modelled.

There is also another and very different class of ruins which
possesses some interest, namely, those of old Callao, overwhelmed
by the great earthquake of 1746, and its accompanying wave. The
destruction must have been more complete even than at Talcahuano.
Quantities of shingle almost conceal the foundations of the walls,
and vast masses of brickwork appear to have been whirled about like
pebbles by the retiring waves. It has been stated that the land
subsided during this memorable shock: I could not discover any
proof of this; yet it seems far from improbable, for the form of
the coast must certainly have undergone some change since the
foundation of the old town; as no people in their senses would
willingly have chosen for their building place the narrow spit of
shingle on which the ruins now stand. Since our voyage, M. Tschudi
has come to the conclusion, by the comparison of old and modern
maps, that the coast both north and south of Lima has certainly

On the island of San Lorenzo there are very satisfactory proofs of
elevation within the recent period; this of course is not opposed
to the belief of a small sinking of the ground having subsequently
taken place. The side of this island fronting the Bay of Callao is
worn into three obscure terraces, the lower one of which is covered
by a bed a mile in length, almost wholly composed of shells of
eighteen species, now living in the adjoining sea. The height of
this bed is eighty-five feet. Many of the shells are deeply
corroded, and have a much older and more decayed appearance than
those at the height of 500 or 600 feet on the coast of Chile. These
shells are associated with much common salt, a little sulphate of
lime (both probably left by the evaporation of the spray, as the
land slowly rose), together with sulphate of soda and muriate of
lime. They rest on fragments of the underlying sandstone, and are
covered by a few inches thick of detritus. The shells higher up on
this terrace could be traced scaling off in flakes, and falling
into an impalpable powder; and on an upper terrace, at the height
of 170 feet, and likewise at some considerably higher points, I
found a layer of saline powder of exactly similar appearance, and
lying in the same relative position. I have no doubt that this
upper layer originally existed as a bed of shells, like that on the
eighty-five-feet ledge; but it does not now contain even a trace of
organic structure. The powder has been analysed for me by Mr. T.
Reeks; it consists of sulphates and muriates both of lime and soda,
with very little carbonate of lime. It is known that common salt
and carbonate of lime left in a mass for some time together partly
decompose each other; though this does not happen with small
quantities in solution. As the half-decomposed shells in the lower
parts are associated with much common salt, together with some of
the saline substances composing the upper saline layer, and as
these shells are corroded and decayed in a remarkable manner, I
strongly suspect that this double decomposition has here taken
place. The resultant salts, however, ought to be carbonate of soda
and muriate of lime, the latter is present, but not the carbonate
of soda. Hence I am led to imagine that by some unexplained means
the carbonate of soda becomes changed into the sulphate. It is
obvious that the saline layer could not have been preserved in any
country in which abundant rain occasionally fell: on the other hand
this very circumstance, which at first sight appears so highly
favourable to the long preservation of exposed shells, has probably
been the indirect means, through the common salt not having been
washed away, of their decomposition and early decay.

I was much interested by finding on the terrace, at the height of
eighty-five feet, EMBEDDED amidst the shells and much sea-drifted
rubbish, some bits of cotton thread, plaited rush, and the head of
a stalk of Indian corn: I compared these relics with similar ones
taken out of the Huacas, or old Peruvian tombs, and found them
identical in appearance. On the mainland in front of San Lorenzo,
near Bellavista, there is an extensive and level plain about a
hundred feet high, of which the lower part is formed of alternating
layers of sand and impure clay, together with some gravel, and the
surface, to the depth of from three to six feet, of a reddish loam,
containing a few scattered sea-shells and numerous small fragments
of coarse red earthenware, more abundant at certain spots than at
others. At first I was inclined to believe that this superficial
bed, from its wide extent and smoothness, must have been deposited
beneath the sea; but I afterwards found in one spot that it lay on
an artificial floor of round stones. It seems, therefore, most
probable that at a period when the land stood at a lower level
there was a plain very similar to that now surrounding Callao,
which, being protected by a shingle beach, is raised but very
little above the level of the sea. On this plain, with its
underlying red-clay beds, I imagine that the Indians manufactured
their earthen vessels; and that, during some violent earthquake,
the sea broke over the beach, and converted the plain into a
temporary lake, as happened round Callao in 1713 and 1746. The
water would then have deposited mud containing fragments of pottery
from the kilns, more abundant at some spots than at others, and
shells from the sea. This bed with fossil earthenware stands at
about the same height with the shells on the lower terrace of San
Lorenzo, in which the cotton-thread and other relics were embedded.
Hence we may safely conclude that within the Indo-human period
there has been an elevation, as before alluded to, of more than
eighty-five feet; for some little elevation must have been lost by
the coast having subsided since the old maps were engraved. At
Valparaiso, although in the 220 years before our visit the
elevation cannot have exceeded nineteen feet, yet subsequently to
1817 there has been a rise, partly insensible and partly by a start
during the shock of 1822, of ten or eleven feet. The antiquity of
the Indo-human race here, judging by the eighty-five feet rise of
the land since the relics were embedded, is the more remarkable, as
on the coast of Patagonia, when the land stood about the same
number of feet lower, the Macrauchenia was a living beast; but as
the Patagonian coast is some way distant from the Cordillera, the
rising there may have been slower than here. At Bahia Blanca the
elevation has been only a few feet since the numerous gigantic
quadrupeds were there entombed; and, according to the generally
received opinion, when these extinct animals were living man did
not exist. But the rising of that part of the coast of Patagonia is
perhaps no way connected with the Cordillera, but rather with a
line of old volcanic rocks in Banda Oriental, so that it may have
been infinitely slower than on the shores of Peru. All these
speculations, however, must be vague; for who will pretend to say
that there may not have been several periods of subsidence,
intercalated between the movements of elevation? for we know that
along the whole coast of Patagonia there have certainly been many
and long pauses in the upward action of the elevatory forces.





The whole group volcanic.
Number of craters.
Leafless bushes.
Colony at Charles Island.
James Island.
Salt-lake in crater.
Natural history of the group.
Ornithology, curious finches.
Great tortoises, habits of.
Marine Lizard, feeds on Sea-weed.
Terrestrial Lizard, burrowing habits, herbivorous.
Importance of reptiles in the Archipelago.
Fish, shells, insects.
American type of organisation.
Differences in the species or races on different islands.
Tameness of the birds.
Fear of man an acquired instinct.

SEPTEMBER 15, 1835.


This archipelago consists of ten principal islands, of which five
exceed the others in size. They are situated under the Equator, and
between five and six hundred miles westward of the coast of
America. They are all formed of volcanic rocks; a few fragments of
granite curiously glazed and altered by the heat can hardly be
considered as an exception. Some of the craters surmounting the
larger islands are of immense size, and they rise to a height of
between three and four thousand feet. Their flanks are studded by
innumerable smaller orifices. I scarcely hesitate to affirm that
there must be in the whole archipelago at least two thousand
craters. These consist either of lava and scoriae, or of
finely-stratified, sandstone-like tuff. Most of the latter are
beautifully symmetrical; they owe their origin to eruptions of
volcanic mud without any lava: it is a remarkable circumstance that
every one of the twenty-eight tuff-craters which were examined had
their southern sides either much lower than the other sides, or
quite broken down and removed. As all these craters apparently have
been formed when standing in the sea, and as the waves from the
trade wind and the swell from the open Pacific here unite their
forces on the southern coasts of all the islands, this singular
uniformity in the broken state of the craters, composed of the soft
and yielding tuff, is easily explained.

Considering that these islands are placed directly under the
equator, the climate is far from being excessively hot; this seems
chiefly caused by the singularly low temperature of the surrounding
water, brought here by the great southern Polar current. Excepting
during one short season very little rain falls, and even then it is
irregular; but the clouds generally hang low. Hence, whilst the
lower parts of the islands are very sterile, the upper parts, at a
height of a thousand feet and upwards, possess a damp climate and a
tolerably luxuriant vegetation. This is especially the case on the
windward sides of the islands, which first receive and condense the
moisture from the atmosphere.

In the morning (17th) we landed on Chatham Island, which, like the
others, rises with a tame and rounded outline, broken here and
there by scattered hillocks, the remains of former craters. Nothing
could be less inviting than the first appearance. A broken field of
black basaltic lava, thrown into the most rugged waves, and crossed
by great fissures, is everywhere covered by stunted, sunburnt
brushwood, which shows little signs of life. The dry and parched
surface, being heated by the noonday sun, gave to the air a close
and sultry feeling, like that from a stove: we fancied even that
the bushes smelt unpleasantly. Although I diligently tried to
collect as many plants as possible, I succeeded in getting very
few; and such wretched-looking little weeds would have better
become an arctic than an equatorial Flora. The brushwood appears,
from a short distance, as leafless as our trees during winter; and
it was some time before I discovered that not only almost every
plant was now in full leaf, but that the greater number were in
flower. The commonest bush is one of the Euphorbiaceae: an acacia
and a great odd-looking cactus are the only trees which afford any
shade. After the season of heavy rains, the islands are said to
appear for a short time partially green. The volcanic island of
Fernando Noronha, placed in many respects under nearly similar
conditions, is the only other country where I have seen a
vegetation at all like this of the Galapagos Islands.

The "Beagle" sailed round Chatham Island, and anchored in several
bays. One night I slept on shore on a part of the island where
black truncated cones were extraordinarily numerous: from one small
eminence I counted sixty of them, all surmounted by craters more or
less perfect. The greater number consisted merely of a ring of red
scoriae or slags cemented together: and their height above the
plain of lava was not more than from fifty to a hundred feet: none
had been very lately active. The entire surface of this part of the
island seems to have been permeated, like a sieve, by the
subterranean vapours: here and there the lava, whilst soft, has
been blown into great bubbles; and in other parts, the tops of
caverns similarly formed have fallen in, leaving circular pits with
steep sides. From the regular form of the many craters, they gave
to the country an artificial appearance, which vividly reminded me
of those parts of Staffordshire where the great iron-foundries are
most numerous. The day was glowing hot, and the scrambling over the
rough surface and through the intricate thickets was very
fatiguing; but I was well repaid by the strange Cyclopean scene. As
I was walking along I met two large tortoises, each of which must
have weighed at least two hundred pounds: one was eating a piece of
cactus, and as I approached, it stared at me and slowly walked
away; the other gave a deep hiss, and drew in its head. These huge
reptiles, surrounded by the black lava, the leafless shrubs, and
large cacti, seemed to my fancy like some antediluvian animals. The
few dull-coloured birds cared no more for me than they did for the
great tortoises.

SEPTEMBER 23, 1835.

The "Beagle" proceeded to Charles Island. This archipelago has long
been frequented, first by the Bucaniers, and latterly by whalers,
but it is only within the last six years that a small colony has
been established here. The inhabitants are between two and three
hundred in number; they are nearly all people of colour, who have
been banished for political crimes from the Republic of the
Equator, of which Quito is the capital. The settlement is placed
about four and a half miles inland, and at a height probably of a
thousand feet. In the first part of the road we passed through
leafless thickets, as in Chatham Island. Higher up the woods
gradually became greener; and as soon as we crossed the ridge of
the island we were cooled by a fine southerly breeze, and our sight
refreshed by a green and thriving vegetation. In this upper region
coarse grasses and ferns abound; but there are no tree-ferns: I saw
nowhere any member of the Palm family, which is the more singular,
as 360 miles northward, Cocos Island takes its name from the number
of cocoa-nuts. The houses are irregularly scattered over a flat
space of ground, which is cultivated with sweet potatoes and
bananas. It will not easily be imagined how pleasant the sight of
black mud was to us, after having been so long accustomed to the
parched soil of Peru and Northern Chile. The inhabitants, although
complaining of poverty, obtain, without much trouble, the means of
subsistence. In the woods there are many wild pigs and goats; but
the staple article of animal food is supplied by the tortoises.
Their numbers have of course been greatly reduced in this island,
but the people yet count on two days' hunting giving them food for
the rest of the week. It is said that formerly single vessels have
taken away as many as seven hundred, and that the ship's company of
a frigate some years since brought down in one day two hundred
tortoises to the beach.

SEPTEMBER 29, 1835.

We doubled the south-west extremity of Albemarle Island, and the
next day were nearly becalmed between it and Narborough Island.
Both are covered with immense deluges of black naked lava, which
have flowed either over the rims of the great caldrons, like pitch
over the rim of a pot in which it has been boiled, or have burst
forth from smaller orifices on the flanks; in their descent they
have spread over miles of the sea-coast. On both of these islands
eruptions are known to have taken place; and in Albemarle we saw a
small jet of smoke curling from the summit of one of the great
craters. In the evening we anchored in Bank's Cove, in Albemarle
Island. The next morning I went out walking. To the south of the
broken tuff-crater, in which the "Beagle" was anchored, there was
another beautifully symmetrical one of an elliptic form; its longer
axis was a little less than a mile, and its depth about 500 feet.
At its bottom there was a shallow lake, in the middle of which a
tiny crater formed an islet. The day was overpoweringly hot, and
the lake looked clear and blue: I hurried down the cindery slope,
and, choked with dust, eagerly tasted the water - but, to my sorrow,
I found it salt as brine.

The rocks on the coast abounded with great black lizards, between
three and four feet long; and on the hills, an ugly yellowish-brown
species was equally common. We saw many of this latter kind, some
clumsily running out of the way, and others shuffling into their
burrows. I shall presently describe in more detail the habits of
both these reptiles. The whole of this northern part of Albemarle
Island is miserably sterile.

OCTOBER 8, 1835.

We arrived at James Island: this island, as well as Charles Island,
were long since thus named after our kings of the Stuart line. Mr.
Bynoe, myself, and our servants were left here for a week, with
provisions and a tent, whilst the "Beagle" went for water. We found
here a party of Spaniards who had been sent from Charles Island to
dry fish and to salt tortoise-meat. About six miles inland and at
the height of nearly 2000 feet, a hovel had been built in which two
men lived, who were employed in catching tortoises, whilst the
others were fishing on the coast. I paid this party two visits, and
slept there one night. As in the other islands, the lower region
was covered by nearly leafless bushes, but the trees were here of a
larger growth than elsewhere, several being two feet and some even
two feet nine inches in diameter. The upper region, being kept damp
by the clouds, supports a green and flourishing vegetation. So damp
was the ground, that there were large beds of a coarse cyperus, in
which great numbers of a very small water-rail lived and bred.
While staying in this upper region, we lived entirely upon
tortoise-meat: the breast-plate roasted (as the Gauchos do carne
con cuero), with the flesh on it, is very good; and the young
tortoises make excellent soup; but otherwise the meat to my taste
is indifferent.

One day we accompanied a party of the Spaniards in their whale-boat
to a salina, or lake from which salt is procured. After landing we
had a very rough walk over a rugged field of recent lava, which has
almost surrounded a tuff-crater at the bottom of which the
salt-lake lies. The water is only three or four inches deep and
rests on a layer of beautifully crystallised, white salt. The lake
is quite circular, and is fringed with a border of bright green
succulent plants; the almost precipitous walls of the crater are
clothed with wood, so that the scene was altogether both
picturesque and curious. A few years since the sailors belonging to
a sealing-vessel murdered their captain in this quiet spot; and we
saw his skull lying among the bushes.

During the greater part of our stay of a week the sky was
cloudless, and if the trade-wind failed for an hour the heat became
very oppressive. On two days the thermometer within the tent stood
for some hours at 93 degrees; but in the open air, in the wind and
sun, at only 85 degrees. The sand was extremely hot; the
thermometer placed in some of a brown colour immediately rose to
137 degrees, and how much above that it would have risen I do not
know for it was not graduated any higher. The black sand felt much
hotter, so that even in thick boots it was quite disagreeable to
walk over it.

The natural history of these islands is eminently curious, and well
deserves attention. Most of the organic productions are aboriginal
creations found nowhere else; there is even a difference between
the inhabitants of the different islands; yet all show a marked
relationship with those of America, though separated from that
continent by an open space of ocean, between 500 and 600 miles in
width. The archipelago is a little world within itself, or rather a
satellite attached to America, whence it has derived a few stray
colonists, and has received the general character of its indigenous
productions. Considering the small size of these islands, we feel
the more astonished at the number of their aboriginal beings, and
at their confined range. Seeing every height crowned with its
crater, and the boundaries of most of the lava-streams still
distinct, we are led to believe that within a period geologically
recent the unbroken ocean was here spread out. Hence, both in space
and time, we seem to be brought somewhat near to that great
fact - that mystery of mysteries - the first appearance of new beings
on this earth.

Of terrestrial mammals there is only one which must be considered
as indigenous, namely a mouse (Mus Galapagoensis) and this is
confined, as far as I could ascertain, to Chatham Island, the most
easterly island of the group. It belongs, as I am informed by Mr.
Waterhouse, to a division of the family of mice characteristic of
America. At James Island there is a rat sufficiently distinct from
the common kind to have been named and described by Mr. Waterhouse;
but as it belongs to the old-world division of the family, and as
this island has been frequented by ships for the last hundred and
fifty years, I can hardly doubt that this rat is merely a variety
produced by the new and peculiar climate, food, and soil, to which
it has been subjected. Although no one has a right to speculate
without distinct facts, yet even with respect to the Chatham Island
mouse, it should be borne in mind that it may possibly be an
American species imported here; for I have seen, in a most
unfrequented part of the Pampas, a native mouse living in the roof
of a newly built hovel, and therefore its transportation in a
vessel is not improbable: analogous facts have been observed by Dr.
Richardson in North America.

Of land-birds I obtained twenty-six kinds, all peculiar to the
group and found nowhere else, with the exception of one lark-like
finch from North America (Dolichonyx oryzivorus) which ranges on
that continent as far north as 54 degrees, and generally frequents
marshes. The other twenty-five birds consist, firstly, of a hawk,
curiously intermediate in structure between a Buzzard and the
American group of carrion-feeding Polybori; and with these latter
birds it agrees most closely in every habit and even tone of voice.
Secondly there are two owls, representing the short-eared and white
barn-owls of Europe. Thirdly a wren, three tyrant-flycatchers (two
of them species of Pyrocephalus, one or both of which would be
ranked by some ornithologists as only varieties), and a dove - all

Online LibraryCharles DarwinThe Voyage of the Beagle → online text (page 37 of 51)