The Voyage of the
Beagle by Charles Darwin Narrator: D.
Selzer-McKenzie
Video: http://youtu.be/RM6uceydXsE
been twice driven
back by heavy southwestern gales, Her Majesty's ship Beagle, a ten-gun brig,
under the command of Captain Fitz Roy, R. N., sailed from Devonport on the 27th
of December, 1831. The object of the expedition was to complete the survey of
Patagonia and Tierra del Fuego, commenced under Captain King in 1826 to 1830,
--to survey the shores of Chile, Peru, and of some islands in the Pacific --and
to carry a chain of chronometrical measurements round the World. On the 6th of
January we reached Teneriffe, but were prevented landing, by fears of our
bringing the cholera: the next morning we saw the sun rise behind the rugged
outline of the Grand Canary island, and suddenly illuminate the Peak of
Teneriffe, whilst the lower parts were veiled in fleecy clouds. This was the
first of many delightful days never to be forgotten. On the 16th of January,
1832, we anchored at Porto Praya, in St. Jago, the chief island of the Cape de
Verd archipelago.
The neighbourhood
of Porto Praya, viewed from the sea, wears a desolate aspect. The volcanic
fires of a past age, and the scorching heat of a tropical sun, have in most
places rendered the soil unfit for vegetation. The country rises in successive
steps of table-land, interspersed with some truncate conical hills, and the
horizon is bounded by an irregular chain of more lofty mountains. The scene, as
beheld through the hazy atmosphere of this climate, is one of great interest;
if, indeed, a person, fresh from sea, and who has just walked, for the first
time, in a grove of cocoa-nut trees, can be a judge of anything but his own
happiness. The island would generally be considered as very uninteresting, but
to anyone accustomed only to an English landscape, the novel aspect of an
utterly sterile land possesses a grandeur which more vegetation might spoil. A
single green leaf can scarcely be discovered over wide tracts of the lava
plains; yet flocks of goats, together with a few cows, contrive to exist. It
rains very seldom, but during a short portion of the year heavy torrents fall,
and immediately afterwards a light vegetation springs out of every crevice.
This soon withers; and upon such naturally formed hay the animals live. It had
not now rained for an entire year. When the island was discovered, the immediate
neighbourhood of Porto Praya was clothed with trees [note 1], the reckless
destruction of which has caused here, as at St. Helena, and at some of the
Canary islands, almost entire sterility. The broad, flat-bottomed valleys, many
of which serve during a few days only in the season as water-courses, are
clothed with thickets of leafless bushes. Few living creatures inhabit these
valleys. The commonest bird is a kingfisher (Dacelo Iagoensis), which tamely
sits on the branches of the castor-oil plant, and thence darts on grasshoppers
and lizards. It is brightly coloured, but not so beautiful as the European
species: in its flight, manners, and place of habitation, which is generally in
the driest valley, there is also a wide difference.
One day, two of the
officers and myself rode to Ribeira Grande, a village a few miles eastward of
Porto Praya. Until we reached the valley of St. Martin, the country presented
its usual dull brown appearance; but here, a very small rill of water produces
a most refreshing margin of luxuriant vegetation. In the course of an hour we
arrived at Ribeira Grande, and were surprised at the sight of a large ruined
fort and cathedral. This little town, before its harbour was filled up, was the
principal place in the island: it now presents a melancholy, but very
picturesque appearance. Having procured a black Padre for a guide, and a
Spaniard who had served in the Peninsular war as an interpreter, we visited a
collection of buildings, of which an ancient church formed the principal part.
It is here the governors and captain-generals of the islands have been buried.
Some of the tombstones recorded dates of the sixteenth century [note 2].
The heraldic
ornaments were the only things in this retired place that reminded us of
Europe. The church or chapel formed one side of a quadrangle, in the middle of
which a large clump of bananas were growing. On another side was a hospital,
containing about a dozen miserable-looking inmates.
We returned to
the Venda to eat our dinners. A considerable number of men, women, and
children, all as black as jet, collected to watch us. Our companions were
extremely merry; and everything we said or did was followed by their hearty
laughter. Before leaving the town we visited the cathedral. It does not appear
so rich as the smaller church, but boasts of a little organ, which sent forth
singularly inharmonious cries. We presented the black priest with a few
shillings, and the Spaniard, patting him on the head, said, with much candour,
he thought his colour made no great difference. We then returned, as fast as
the ponies would go, to Porto Praya.
Another day we
rode to the village of St. Domingo, situated near the centre of the island. On
a small plain which we crossed, a few stunted acacias were growing; their tops
had been bent by the steady trade-wind, in a singular manner --some of them
even at right angles to their trunks. The direction of the branches was exactly
N. E. by N., and S. W. by S., and these natural vanes must indicate the
prevailing direction of the force of the trade-wind. The travelling had made so
little impression on the barren soil, that we here missed our track, and took
that to Fuentes. This we did not find out till we arrived there; and we were
afterwards glad of our mistake. Fuentes is a pretty village, with a small
stream; and everything appeared to prosper well, excepting, indeed, that which
ought to do so most --its inhabitants. The black children, completely naked,
and looking very wretched, were carrying bundles of firewood half as big as
their own bodies.
Near Fuentes we
saw a large flock of guinea-fowl --probably fifty or sixty in number. They were
extremely wary, and could not be approached. They avoided us, like partridges
on a rainy day in September, running with their heads cocked up; and if
pursued, they readily took to the wing.
The scenery of
St. Domingo possesses a beauty totally unexpected, from the prevalent gloomy
character of the rest of the island. The village is situated at the bottom of a
valley, bounded by lofty and jagged walls of stratified lava. The black rocks
afford a most striking contrast with the bright green vegetation, which follows
the banks of a little stream of clear water. It happened to be a grand
feast-day, and the village was full of people. On our return we overtook a
party of about twenty young black girls, dressed in excellent taste; their
black skins and snow-white linen being set off by coloured turbans and large
shawls. As soon as we approached near, they suddenly all turned round, and
covering the path with their shawls, sung with great energy a wild song,
beating time with their hands upon their legs. We threw them some vintems,
which were received with screams of laughter, and we left them redoubling the
noise of their song.
One morning the view
was singularly clear; the distant mountains being projected with the sharpest
outline on a heavy bank of dark blue clouds. Judging from the appearance, and
from similar cases in England, I supposed that the air was saturated with
moisture. The fact, however, turned out quite the contrary. The hygrometer gave
a difference of 29.6 degs., between the temperature of the air, and the point
at which dew was precipitated. This difference was nearly double that which I
had observed on the previous mornings. This unusual degree of atmospheric
dryness was accompanied by continual flashes of lightning. Is it not an
uncommon case, thus to find a remarkable degree of aerial transparency with
such a state of weather?
Generally the
atmosphere is hazy; and this is caused by the falling of impalpably fine dust,
which was found to have slightly injured the astronomical instruments. The
morning before we anchored at Porto Praya, I collected a little packet of this
brown-coloured fine dust, which appeared to have been filtered from the wind by
the gauze of the vane at the masthead. Mr. Lyell has also given me four packets
of dust which fell on a vessel a few hundred miles northward of these islands.
Professor Ehrenberg [note 3] finds that this dust consists in great part of
infusoria with siliceous shields, and of the siliceous tissue of plants. In
five little packets which I sent him, he has ascertained no less than
sixty-seven different organic forms! The infusoria, with the exception of two
marine species, are all inhabitants of fresh-water. I have found no less than
fifteen different accounts of dust having fallen on vessels when far out in the
Atlantic. From the direction of the wind whenever it has fallen, and from its
having always fallen during those months when the harmattan is known to raise
clouds of dust high into the atmosphere, we may feel sure that it all comes
from Africa. It is, however, a very singular fact, that, although Professor
Ehrenberg knows many species of infusoria peculiar to Africa, he finds none of
these in the dust which I sent him. On the other hand, he finds in it two
species which hitherto he knows as living only in South America. The dust falls
in such quantities as to dirty everything on board, and to hurt people's eyes;
vessels even have run on shore owing to the obscurity of the atmosphere. It has
often fallen on ships when several hundred, and even more than a thousand miles
from the coast of Africa, and at points sixteen hundred miles distant in a
north and south direction. In some dust which was collected on a vessel three
hundred miles from the land, I was much surprised to find particles of stone
above the thousandth of an inch square, mixed with finer matter. After this
fact one need not be surprised at the diffusion of the far lighter and smaller
sporules of cryptogamic plants.
The geology of
this island is the most interesting part of its natural history. On entering
the harbour, a perfectly horizontal white band, in the face of the sea cliff,
may be seen running for some miles along the coast, and at the height of about
forty-five feet above the water. Upon examination this white stratum is found
to consist of calcareous matter with numerous shells embedded, most or all of
which now exist on the neighbouring coast. It rests on ancient volcanic rocks,
and has been covered by a stream of basalt, which must have entered the sea
when the white shelly bed was lying at the bottom. It is interesting to trace
the changes produced by the heat of the overlying lava, on the friable mass,
which in parts has been converted into a crystalline limestone, and in other
parts into a compact spotted stone Where the lime has been caught up by the
scoriaceous fragments of the lower surface of the stream, it is converted into
groups of beautifully radiated fibres resembling arragonite. The beds of lava
rise in successive gently-sloping plains, towards the interior, whence the
deluges of melted stone have originally proceeded. Within historical times, no
signs of volcanic activity have, I believe, been manifested in any part of St.
Jago. Even the form of a crater can but rarely be discovered on the summits of
the many red cindery hills; yet the more recent streams can be distinguished on
the coast, forming lines of cliffs of less height, but stretching out in advance
of those belonging to an older series: the height of the cliffs thus affording
a rude measure of the age of the streams.
During our stay,
I observed the habits of some marine animals. A large Aplysia is very common.
This sea-slug is about five inches long; and is of a dirty yellowish colour
veined with purple. On each side of the lower surface, or foot, there is a
broad membrane, which appears sometimes to act as a ventilator, in causing a
current of water to flow over the dorsal branchiae or lungs. It feeds on the
delicate sea-weeds which grow among the stones in muddy and shallow water; and
I found in its stomach several small pebbles, as in the gizzard of a bird. This
slug, when disturbed, emits a very fine purplishred fluid, which stains the water
for the space of a foot around. Besides this means of defence, an acrid
secretion, which is spread over its body, causes a sharp, stinging sensation,
similar to that produced by the Physalia, or Portuguese man-of-war.
I was much
interested, on several occasions, by watching the habits of an Octopus, or
cuttle-fish. Although common in the pools of water left by the retiring tide,
these animals were not easily caught. By means of their long arms and suckers,
they could drag their bodies into very narrow crevices; and when thus fixed, it
required great force to remove them. At other times they darted tail first,
with the rapidity of an arrow, from one side of the pool to the other, at the
same instant discolouring the water with a dark chestnut-brown ink. These
animals also escape detection by a very extraordinary, chameleonlike power of
changing their colour. They appear to vary their tints according to the nature
of the ground over which they pass: when in deep water, their general shade was
brownish purple, but when placed on the land, or in shallow water, this dark
tint changed into one of a yellowish green. The colour, examined more
carefully, was a French grey, with numerous minute spots of bright yellow: the
former of these varied in intensity; the latter entirely disappeared and
appeared again by turns. These changes were effected in such a manner, that
clouds, varying in tint between a hyacinth red and a chestnutbrown [note 4],
were continually passing over the body. Any part, being subjected to a slight
shock of galvanism, became almost black: a similar effect, but in a less
degree, was produced by scratching the skin with a needle. These clouds, or
blushes as they may be called, are said to be produced by the alternate
expansion and contraction of minute vesicles containing variously coloured
fluids [note 5].
This cuttle-fish
displayed its chameleon-like power both during the act of swimming and whilst
remaining stationary at the bottom. I was much amused by the various arts to
escape detection used by one individual, which seemed fully aware that I was
watching it. Remaining for a time motionless, it would then stealthily advance
an inch or two, like a cat after a mouse; sometimes changing its colour: it
thus proceeded, till having gained a deeper part, it darted away, leaving a
dusky train of ink to hide the hole into which it had crawled.
While looking for
marine animals, with my head about two feet above the rocky shore, I was more
than once saluted by a jet of water, accompanied by a slight grating noise. At
first I could not think what it was, but afterwards I found out that it was
this cuttle-fish, which, though concealed in a hole, thus often led me to its
discovery. That it possesses the power of ejecting water there is no doubt, and
it appeared to me that it could certainly take good aim by directing the tube
or siphon on the under side of its body. From the difficulty which these
animals have in carrying their heads, they cannot crawl with ease when placed
on the ground. I observed that one which I kept in the cabin was slightly
phosphorescent in the dark.
St. Paul's Rocks
In crossing the
Atlantic we hove-to during the morning of February 16th, close to the island of
St. Paul's. This cluster of rocks is situated in 0 degs. 58' north latitude,
and 29 degs. 15' west longitude. It is 540 miles distant from the coast of
America, and 350 from the island of Fernando Noronha. The highest point is only
fifty feet above the level of the sea, and the entire circumference is under
three-quarters of a mile. This small point rises abruptly out of the depths of
the ocean. Its mineralogical constitution is not simple; in some parts the rock
is of a cherty, in others of a felspathic nature, including thin veins of
serpentine. It is a remarkable fact, that all the many small islands, lying far
from any continent, in the Pacific, Indian, and Atlantic Oceans, with the
exception of the Seychelles and this little point of rock, are, I believe,
composed either of coral or of erupted matter. The volcanic nature of these
oceanic islands is evidently an extension of that law, and the effect of those
same causes, whether chemical or mechanical, from which it results that a vast
majority of the volcanoes now in action stand either near sea-coasts or as
islands in the midst of the sea.
The rocks of St. Paul appear from a distance of a brilliantly white
colour. This is partly owing to the dung of a vast multitude of seafowl, and
partly to a coating of a hard glossy substance with a pearly lustre, which is
intimately united to the surface of the rocks. This, when examined with a lens,
is found to consist of numerous exceedingly thin layers, its total thickness
being about the tenth of an inch. It contains much animal matter, and its
origin, no doubt, is due to the action of the rain or spray on the birds' dung.
Below some small masses of guano at Ascension, and on the Abrolhos Islets, I
found certain stalactitic branching bodies, formed apparently in the same
manner as the thin white coating on these rocks. The branching bodies so
closely resembled in general appearance certain nulliporae (a family of hard
calcareous seaplants), that in lately looking hastily over my collection I did
not perceive the difference. The globular extremities of the branches are of a
pearly texture, like the enamel of teeth, but so hard as just to scratch
plate-glass. I may here mention, that on a part of the coast of Ascension,
where there is a vast accumulation of shelly sand, an incrustation is deposited
on the tidal rocks by the water of the sea, resembling, as represented in the
woodcut, certain cryptogamic plants (Marchantiae) often seen on damp walls. The
surface of 
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