Alexander von Humboldt.

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vices, in which heat was perceptible. In fact, the E-uptto,'*
volcano has not been active at the summit for tliousands
of years, its eruptions having been from the sides, and
the depth of the crater is only about 106 feet. After
examining the objects tliat presented themselves in tliis
elevated spot, and enjoying the vast prospect, the
travellers commenced their descent, and towards evening
reached tlie port of Orotava.

The Peak of TenerifFe forms a pyramidal mass having Dimension*
a circumference at the base of more than 116,110 yards, "^'■'^p^^'^
and a height of 12,176 feet.* Two-thirds of the mass
are covered with vegetation, the remaining part being
steril, and occupying about ten square leagues of surface.
The cone is very small in proportion to the size of the
mountain, it having a height of only 637 feet, or ^^^ of
the whole. The lower part of the island is composed of Geological
basalt and other igneous rocks of ancient formation, and ''■*^'■''■"
is separated from the more recent lavas and the products
of the present volcano by strata of tufa, puzzolana, and
clay. The first that occur in ascending the Peak are of
a black colour, altered by decomposition, and sometimes
porous. Their basis is wacke, and has usually an irre-
gular, but sometimes a conchoidal fracture. They are
divided into very tliin layers, and contain olivine,
magnetic iron, and augite. On the first elevated plain,
that of Retama, the basaltic depositcs disappear beneath
heaps of ashes and pumice. Beyond this are lavas,

" Various measurements have been made of the heij^^Iit of the
Peak.of Tenerifte ; but Humboldt, after enumerating- fourteen, states
that the followint;- alone can be considered as deservinjr of confidence :

Borda's, by trigonometry, 1905 toises.

Borda's, by the barometer, 1976

Lamanou's, by the same, 1902

Cordier's, by the same, 1920

The average of these four observations makes the height 1926
toises; but if the barometric measurement of Borda be rejected, as
liable to objections particularh- stated by our author, the mean of
the remainmg measurement is 19119 toises, or 12.20!i Engli - h feet.
It is seen above, that the height adopted by Humboldt is 1904 toises,
or 12,176 English feet.



4(;



VOLCANIC KlUPTIONS.



Accounts of
eruptions.



CHAP. III. vitli a basis of pitch-stone and obsidian, of a blacl<isli-
~ brown or deep olive-green colour, and containing crystals
of felspar, which are seldom vitreous. In the middle of
the Malpays or second j)latform are found, amongst the
glassy kinds, blocks of greenish-gray clinkstone or
porphyry-slate. Obsidian of several varieties is exceed-
ingly abundant on the Peak, as well as pumice, the
latter being generally of a white colour ; and the crater
contains an enormous quantity of sulphur.

Tlie oldest written testimony, in regard to the activity
of the volcano, dates at the beginning of the sixteenth
century, and is contained in the narrative of Aloysio
Cadamusto, who landed in the Canaries in 1505. In
1558, 164(5, and 1677, eruptions took place in the isle of
Pal ma; and on the 31st December 1704, the Peak of
Tencriffe exlii])ited a lateral burst, preceded by tremen-
dous earthquakes. On the 5th of January 1705, another
opening occurred, the lavas produced by which filled
the whole valley of Fasnia. This aperture closed on
the 13th of January; but on the 2d of February, a
third furmcd in the Canada de Arafo, the stream from
which divided into three currents. On the 5th May
1706, another eruption supervened, which destroyed the
populous and opulent city of Garachico. In 1730, on
the 1st September, the island of Lancerota was violently
convulsed ; and on the 9th June 1798, the IVak emitted
a great quantity of matter, which continued to run three
months and six days.

The island of Teneriffe presents five zones of vegeta-
tion, arranged in stages one above another, and occupy-
ing a i)0<-pendicular height of 3730 yards.

1. The Region of Vines extends from the shores to an
elevation varying from 430 to 040 yards, and is the
only part carefully cultivated. It exhibits various
sjiecies of arl)orescent Eujihorbiae, Mesembryanthcma,
tlie Cacalia kleinia, tlie DraccEua, and other plants,
whose naked and tortuous trunks, succulent leaves, and
bluish-green tints, constitute features distinctive of the
viyctjition of Africa. In this zone are raised the datc-



7M\\ts of
I i;;;etution



ZONES OF VEGETATIOX. 47

tree, the plantain, tlie sugar-cane, the Indian-fig, the chap, ul
arum colocasia, the olive, the fruit-trees of Europe, the —
vine, and wheat.

2. The Region of Laurels is that which forms the Laurels.
woody part of Tencriffe, where the surface of the ground

is always verdant, being plentifully watered by springs.
Four kinds of laurel, an oak, a wild olive, two species of
iron-tree, the arbutus callicarpa, and other evergreens,
adorn this zone. The trunks ai-e covered by the ivy of
the Canaries and various twining shrubs, and the woods
are filled with numerous species of fern. The hyperi-
cum, and other showy plants, enrich with their beautiful
flowers the verdant carpet of moss and grass.

3. The Region of Pines, which commences at the pines
height of 1920 yards, and has a breadth of 850, is
characterized by a vast forest of trees, resembling the
Scotch fir, intermixed with juniper.

4. The fourth zone is remarkable chiefly for the pro-
fusion of retaina, a species of broom, which forms oases
in the midst of a wiile sea of ashes. It grows to the
height of nine or ten feet, is ornamented with fragrant
flowers, and furnishes food to the goats, which have run
wild on the Peak from time immemorial.

5. The fifth zone is the Region of the Grasses, in cras-cK.
which some species of these supply a scanty covering to

the heaps of pumice, obsidian, and lava. A few crypto-
gamic plants are observed higher; but the summit is
entirely destitute of vegetation.*

* Tde above is the account of tlie Peak of Teneriffe given in
his text, by Humboldt after M. Brou.s.sonnet ; but in a later por-
tion of liis work he substitutes the foliowint;' divisions of M. Von
Bucii, wliich he considers as more correct : — Tliis illusti ious geologist
distinguishes, 1st, The Region of African forms — 41d yartis;
2d, The Region of Vines and Cereal Plants 416 — 916 yards; 3d,
The Region of Laurels 916 — 1450 yards ; 4th, The Region of Pines
1450-2090 yards ; 5th, The Region of the Retama 2090— 36f!7
yards. This last plant is onlj* (bund in Tenerift'e, none of the
mountains in the other islands rising within its inferior limit (2130
yards) e.\cepling Palma, and the summit of its Peak is only barren
and naked rocks. The gramiueou)' plants are very rare, and do not
form a particular zone.



48 riRES OF ST JOHN.

CHAP. III. Thus the wliole island may be considered as a forest
Gencrai ^^ laurels, avbutusrs, and pines, of which the external
iiiaiacter of margin only has boon in some measure cleared, while
the island, ^j^^ central part consi.sts of a rocky and steril soil, unfit

even for pasturage.
Eve of St. The following day was passed by our travellers in

JohiL visiting the neighbourhood of Orotava, and enjoying an

agreeable company at Mr Cologan's. On the eve of St
John, they were present at a pastoral fete in the garden
of Mr Little, who had reduced to cultivation a hill
covered with volcanic substances, from which there is a
magnificent view of the Peak, the villages along the
coist, and the isle of Palma. Early in the evening, the
volcano suddenly exhibited a most extraordinary spec-
tacle, the sheplierds having, in conformity to ancient
custom, lighted the fires of St John ; the scattered
masses of which, with the columns of smoke driven by
the wind, formed a fine contrast to the deep verdure of
tlie woods that covered the sides of the mountain, while
the silence of nature was broken at intervals hy tlie
bhouts of joy which came from afar.



DEPARTURE FROM SANTA CRUZ. 49



CHAPTER IV.

Passage from Teneriffe to Cumana.

Departure from Santa Cruz — Floating' Seaweeds — Flying-fish —
Stars — Malignant Fever — Island of" Tobag;o — Death of a Pas-
senger — Island of Coche — Port of Cumana — Observations made
during the Voyage; Temperature of the Air; Temperature ot
the Sea ; Hygrometrical State of the Air ; Colour of the Sky and
Ocean.

Having sailed from Santa Cruz on the evening of the chap, iv
25th of June, with a strong wind from the north-east, i^^^y^
our travellers soon lost sight of the Canary Islands, the Santa Cruz.
mountains of which were covered with reddish vapour,
the Peak alone appearing at intervals in the breaks.
The passage from Teneriffe to Cumana was performed
in twenty days, the distance being 3106 miles.

The wind gradually subsided as they retired from the changes of
African coast. Short calms of several hours occasionally '*^'"'^-
took place, which were regularly interrupted by slight
squalls, accompanied by masses of dark clouds, emitting
a few large drops of rain, but without thunder. To the
north of the Cape Verd Islands they met with large
patches of floating seaweed (^Fucus natans), which Fioatincr
grows on submarine rocks, from the equator to forty
degrees of latitude on either side. These scattered
plants, however, must not be confounded with the vast
beds, said by Columbus to resemble extensive meadows,
and which inspired with terror the crew of the Santa
Maria. From a comparison of numerous journals, it
appears that there are two such fields of seaweed in the
c



;J0 FLOATING SEAWEEDS.

CHAP. IV. Atlantic. The largest occurs a little to the west of the
FicuiTof meridian of Fayal, one of the Azores, between 25° and
fcc.1 weed. 3(30 Qf latitude. The temperature of the ocean there is
between G0-8° and 68° ; and the north-west winds,
which blow sometimes with impetuosity, drive floating
islands of those weeds into low latitudes, as far as the
parallels of 24^ and even 20°. Vessels returning to
Europe from ]Monte Video, or the Cape of Good Hope,
pass througli this marine meadow, which the Spanish
pilots consider as lying half-way between the West
Indies and the Canaries. The other section is not so
well known, and occupies a smaller space between lat.
22° and 2G° of N., two hundred and seventy-six miles
eastward of the Bahama Islands.
r ouing Although a species of seaweed, the Laminaria py-

rifera of Lamouroux, has been observed with stems 850
feet in length, and although the growth of these plants
is exceedingly rapid, it is yet certain that in those seas
the fuci are not fixed to the bottom, but float in de-
tached parcels at the surface. In this state vegetation,
it is obvious, cannot continue longer than in the branch
of a tree separated from the trunk ; and it may there-
fore be supposed, that floating masses of these weeds
occurring for ages in the same position owe their origin
to submarine rocks, which continually supply what has
been carried ott" by the equinoctial currents. But the
causes by which tliese ])lants are detached are not yet
sufficiently known, although the author just named has
shown that fuci in general separate with great facility
after the period of fructification.
FiylDg-fisli. Beyond 22^ of latitude they found the surfoce of the
sea covered with flying-fish (Exocetus volitaiis), which
sprung into the air to a height of twelve, fifteen, and
even eighteen feet, and sometimes fell on the deck.
The great size of the swimming-bladder in these ani-
mals, being more than one-half of their body, as well as
that of the j)ectoral fins, enaldc them to traverse in the
air a space of twenty-four feet horizontal distance before
falling again into the water. They are incessantly



FLYING-FISH — CONSTELLATIONS. 51

pursued by doljihins while under the surface, and when chap. iv.
flying are attacked by frigate-birds and other predatory ^^. 7T~,
species. Yet it does not seem that they leap into the frigate birds,
atmosphere merely to avoid their enemies ; for, like
swallows, they move by thousands in a right line, and
always in a direction opposite to that of the waves.
The air contained in the swimming-bladder had been
supposed to be pure oxygen ; but Humboldt found it to
consist of ninety-four parts of azote, four of oxj^gen,
and two of carbonic acid.

On the 1st of July they met with the Avreck of a wreck- of a
vessel, and on the 3d and 4th crossed that part of the vessel.
ocean where the charts indicate the bank of the Maal-
Stroom, which, however, is of very doubtful existence.
As they approached this imaginary whirlpool they ob-
served no other motion in the waters than that produced
by a current bearing to the north-west.

From tlie time when they entered the torrid zone Nocturnal
(the 27th June) they never ceased to admire the noc- ^w"'^ °^
turnal beauty of the southern sky, which gradually
disclosed new constellations to their view. " One ex-
periences an indescribable sensation," says Humboldt,
" when, as he approaches the equator, and especially in
passing from the one hemisphere to the other, he sees
the stars with which he has been familiar from infancy
gradually approach the horizon and finally disappear.
Nothing impresses more vividly on the inind of the
traveller the vast distance to which he has been re-
moved from his native country than the sight of a new
firmament. The grouping of the larger stars, the Aspect of tlit
scattered nebulse rivalling in lustre the milky- way, and ^'g^vg^
spaces remarkable for their extreme darkness, give the
southern heavens a peculiar aspect. The sight even
strikes the imagination of those who, although ignorant
of astronomy, find pleasure in contemplating the celestial
vault, as one admires a fine landscape or a majestic site.
Without being a botanist, the traveller knows the torrid
zone by the mere sight of its vegetation ; and without
the possession of astronomical knowledge, perceives that



52 MALIGNANT FEVER ON BOARD,

CHAP. IV. he is not iu Europe, -when he sees rising in the horizon
^ — ^ the great constellation of the Ship, or the phosphores-

stcUutions. cent clouds of ^Magellan. In the equinoctial regions, the
earth, the sky, and all their garniture, assume an exotic
character."

Intertropical The intertropical seas being usually smooth, and the

Tciyage. vessel being impelled by the gentle breezes of the trade-
wind, the passage from the Cape Verd Islands to
Cumana was as pleasent as could be desired ; but as
they approached the West Indies a malignant fever
disclosed itself on board. The ship was very much
encumbered between decks, and from the time they
passed the tropic the thermometer stood from 93° to

Malignant 9G'8°. Two sailors, several passengers, two negroes

fever from the coast of Guinea, and a mulatto child, Avere

attacked. An ignorant Galician surgeon ordered bleed-
mgs, to obviate the " heat and corruption of the blood ;"
but little exertion had been made in attempting to
diminish the danger of infection, and there was not an
ounce of bark on board. A sailor, who had been on the
point of expiring, recovered his health in a singular

Onrativc manner. 11 is hammock having been so hung that the
sacrament could not be administered to him, he was
removed to an airy place near the hatchway, and left
there, his death being expected every moment. The
transition from a hot and stagnant to a fresher and
purer atmosphere gradually restored him, and his re-
covery i'urnislied the doctor with an additional proof of
the necessity of bleeding and evacuation, — a treatment
of which the iatal effects soon became perceptible.

n u;;Ji On the 13th, early in the morning, very high land

«».Mtlier ^y.j^^ gppjj_ rj,jj^ ^^.j^^j j^jg^^ j^^^.^^ ^j^^ g^^^ ^^.^g rough,

large drops of rain fell at intervals, and there was every
appearance of stormy weather. Consideraltle doubt
existed as to the latitude and longitude, which was
however, removed by observations made by our tra-
vellers, and the appearance of the island of Tobago.
Tills little i.sland is a heap of rocks, the dazzling white-
ness of which forms an agreeable contrast with the



MALIGNANT FEVER. 53

verdure of the scattered tufts of trees upon it. The chap, iv
mountains are covered with very tall opunticc, which isijmXof
alone are enough to apprize the navigator that he has Tobago,
arrived on an American coast.

After doul)ling the north cape of Tobago and the Optical
point of St Giles, they discovered from the mast-head '^'^•^1"'°°-
what they regarded as a hostile squadron ; which how-
ever turned out to be only a group of rocks. Crossing
the shoal which joins the former island to Grenada, they
found that, although the colour of the sea was not visibly
changed, the thermometer indicated a temperature
several degrees lower than that of the neighbouring
parts. The wind diminished after sunset, and the
clouds dispersed as the moon reached the zenith.
Numerous falling-stars were seen on this and the fol-
lowing nights.

On the 14th, at sunrise, they were in sight of the p.neca del-
Bocca del Drago, and distinguished the island of Chaca- J^rago.
chacarreo. When 17 miles distant from the coast, they
experienced, near Punta de la Baca, the effect of a
current which drew the ship southward. Heaving the
lead, they found from 230 to 275 feet, with a bottom of
very tine green clay, — a depth much less than, ac-
cording to Dampier's rule, might have been expected
in the vicinity of a shore formed of very elevated and
perpendicular mountains.

The disease which had broken out on board the prngress of
Pizarro made rapid progress from the time they ap- disease,
proached the coast. The thermometer kept steady at
night between 71'6° and 73*4°, and during the day rose
to between 75'2° and 80'6°. The determination to the
head, the extreme dryness of the skin, the prostration
of strength, and all the other symptoms became more
alarming : but it was hoped that the sick would recover
as soon as they were landed on the island of Margarita
or at the port of Cumana, both celebrated for their
great salubrity. This hope, however, was not entirely
realized, for one of the passengers fell a victim to the
distemper. He was an Asturian, nineteen years of age,



5-1 MALIGNANT FEVER.

CHAP. IV. the only son of a poor widow. Various circumstances
DeathTf a Combined to render the death of this young man affect-
passenger ing. He was of an exceedingly gentle disposition, bore
the marks of great sensibility, and had lei't his native
land against his inclination, with the view of earning an
independence and assisting his reluctant mother, under
the protection of a rich relation, who resided in the
island of Cuba. From the commencement of his illness
he had fallen into a lethargic state, interrupted by
accessions of delirum, and on the third day expired,
fidelity Another Asturian, who was still younger, did not leave
ment**^^' ^^^^ ^^^'^ of liis dying friend for a moment, and yet es-
caped tlie disea.se. He had intended to accomi)any his
countryman to Cuba, to be introduced by him to the
house of his relative, on whom all their hopes rested ;
and it was distressing to see his deep sorrow, and to hear
him curse the fatal counsels which had thrown him
into a foreign climate, where he found himself alone and
destitute.
Melancholy " We were assembled on the deck," says our eloquent
Impressions, author, " absorljed in melancholy reflections. It was
no longer doul)tful that the fever which j)revailed on
board had of late assumed a fatal character. Our eyes
were fixed on a mountainous and desert coast, on which
the moon shone at intervals through the clouds. The
sea, gently agitated, glowed with a feeble phosphoric
light. No sound came on tlie car save the monotonous
cry of some large sea-birds that seemed to be seeking
tile shore. A deep calm reignfd in these solitary
places ; but tliis calm of external nature accorded ill
witli tiie jjainful feelings wliich agitated us. About
Dcatli-bcU. eight tiie death-bell was slowly tolled. At this doleful
signal the sailors ceased from their work, and threw
themselves on their knees to offer up a short prayer, —
an afil-eting ceremony, which, while it recalls the times
when tlic primitive Ciiristians considered tliemselves as
members of tiie same family, seems to unite men by the
feeling of a common evil. In the course of the night
the body of the Asturian was brought upon deck, and



MALIGNANT FEVEU. 55

the priest prevailed upon them not to throw it into the ciIAP. rv.

sea until after sunrise, in order that he might render to

it the last rites, in conformity to the practice of the rites. '
Romish church. There was not an individual on board
who did not feel for the fate of this young man, whom
we had seen a few days before full of cheerfulness and
health."

The passengers who had not been affected by the Quittine
disease resolved to leave the ship at the first place the ship,
where she should touch, and there wait the arrival of
another packet to convey them to Cuba and Mexico.
Our travellers also thought it prudent to land at Cumana,
more especially as they wished not to visit New Spain ,
until they had remained for some time on the coasts of
Venezuela and Paria, and examined the beautiful plants
of which Bosc and Bredemeyer collected specimens on
their voyage to Terra Firma, and which Humboldt had
seen in the gardens of Schonbrunn and Vienna. Tliis re- porhmate
solution had a liappy influence upon the direction of their results.
joumej'-, as will subsequently be seen, and perhaps was
the occasion of securing for them the health wliich they
enjoyed during a long residence in the equinoctial
regions. They were by this means fortunate enough to
pass the time when a European recently landed runs
the greatest danger of being affected by the yellow
fever, in the hot but dry and salubrious climate o
Cumana.

As the coast of Paria stretches to the west, in the q^^^^. q^
form of perpendicular cliffs of no great height, they Paria.
were long without perceiving the bold shores of the
island of Margarita, where they intended to stop for the
purpose of obtaining information respecting the English
cruisers. Toward eleven in the morning of the 15th,
they observed a very low islet covered with sand, and
destitute of any trace of culture or habitation. Cactuses vegetation,
rose here and there, from a scanty soil which seemed to
have an undulating motion, in consequence of the extra-
ordinary refraction the solar rays undergo in passing
through the strata of air in contact with a strongly-



5G



COAST OF NEAr ANDALUSIA.



CHAP. IV.

Peri'ltJ'ity
of the
voyugcrs.



Native
luduius.



Caman,^



Plants and



Tempera-
ture.



heated surface. The deserts and sandy shores of all
countries present this appearance. The aspect of this
phice not corresponding with the ideas which they had
ibrnu'd of the island of Margarita, and the greatest per-
plexity existing as to their position and course, tliey
cast anchor in shallow water, and were visited by some
Guayquerias in two canoes, constructed each of the
single trunk of a tree. These Indians, who were of a
coppery colour and very tall, informed them that they
had kept too far south, that the low islet near which
they were at anchor was tlie island of Coche, and that
Spanish vessels coining from Europe usually passed to
the northward of it. The master of one of the canoes
offered to remain on board as coasting pilot, and towards
evening the captain set sail.

On the IGtli they beheld a verdant coast of picturesque
appearance ; the mountains of New Andalusia bounded
the southern horizon, and the city of Cumana and its
castle appeared among groups of trees. They anchored
in the port al)out nine in the morning, when the sick
crawled on deck to enjoy the sight. The river was
bordered with cocoa-trees more than sixty feet high, —
the plain was covered witli tuits of cassias, capers, and
arborescent mhnosas, while the pinnated leaves of the
palms were conspicuous on the azure of a sky unsullied
by the least trace of vapour. A dazzling light was
spread along the white liills clothed with cylindrical
cactuses, and over the smooth sea, the shores of which
were peopled by pelicans, egrets, and flamingoes. Everj>
thing announced the magnificence of nature in the
equinoctial regions.

Before accompanying our learned friends to the city
of Cumana, we may here take a glance of the physical
observations made by them during the voyage, and
whicii refer to tlie temperature of the air and sea, and
other subj<-cts of general interest.



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