Alexander von Humboldt.

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which has prol)ably l)een raised by volcanic agency.
'Jacking during tlie night between Montana Clara and
this islet, tliey were several times in great danger among
«hi;lve8 towards which they were drawn by the motion

Clianfjc of



of the water ; but the wind freshening in the morning, CHAP. ii.
they succeeded in passing the channel, and sailed along ^^^{^^
the coasts of Lancerota, Lobos, and Forteventura. of atmos-

The haziness of the atmosphere prevented them from ^ '*"'■
seeing the Peak of TenerifFe during the whole of their
passage from Lancerota ; but our traveller, hi his nar-
rative, states the following interesting circumstances
relative to the distance at which mountains may be seen.
If the height of the Peak, he says, is 12,182 feet, as indi-
cated by the last trigonometrical measurement of Borda,
its summit ought to be visible at the distance of 148
miles, supposing the eye at the level of the ocean, and
the refraction equal to 0*079 of the distance. Navigators
who frequent these latitudes find that the Peaks of Te- Peaks of
nerifFe and the Azores are sometimes observed at very
great distances, while at other times they cannot be seen
when the interval is considerably less, although the sky
is clear. Such circumstances are of importance to navi-
gators, who, in returning to Europe, impatiently wait
for a sight of these mountains to rectify their longitude.
The constitution of the atmosphere has a great influence
on the visibility of distant objects, the transparency of
the air being much increased when a certain quantity of
water is uniformly diffused through it.

It is not surprising that the Peak of Teneriffe should Causes of
be less frequently visible at a great distance than the Jjfvi^luf
tops of the Andes, not being like them invested with
perpetual snow. The Sugar-loaf, which constitutes the
summit of the former, no doubt reflects a great degree
of light, on account of the white colour of the pumice
with which it is covered ; but its height does not form
a twenty-secondth part of the total elevation, and the
sides of the volcano are coated with blocks of dark-
coloured lava, or with luxuriant vegetation, the masses
of which reflect little light, the leaves of the trees being
separated by shadows of greater extent than the illu-
minated parts.

Hence the Peak of TenerifFe is to be referred to the
class of mountains which are seen at great distances only



ciiAi'. u ill what Bouguer calls a negative manner, or because
Cia<sificrttioii ^^^*-'y intercept the light transmitted from the extreme
oiiiioiuiuiiis. limits of tlie atmosphere ; and we perceive their ex-
istence only by means of the difference of intensity that
subsists between the liglit which surrounds them, and
that reflected by the particles of air placed between the
object of vision and the, observer. In receding from
Teneriffe, the Sugar-loaf is long seen in a positive
Tlic sugai- manner, as it reflects a whitish light, and detaches
luaf. itself clearly from the sky ; but as this terminal cone is

only 512 feet high, by 250 in breadth at its summit, it
hiis been questioned whether it can be visible beyond
the distance of 139 miles. If it be admitted that the
mean breadth of tiie Sugar-loaf is G395 feet, it will still
subtend, at the distance now named, an angle of more
than three minutes, which is enough to render it visible ;
and were the height of the cone greatly to exceed its
basis, the angle might be still less, and the mass yet
make an impression on our organs ; for it has been
jiruved by micrometrical observations, that the limit of
vi.>ion is one minute only when the dimensions of objects
are the same in all directions.
EffcTtof As the visibility of an object, which detaches itself

ros'iilm" from the sky of a brown colour, depends on the quan-
tities of light the eye meets in two lines, of which one
ends at the mountain and the other is prolonged to the
surface of tlie aerial ocean, it follows that the farther
we remove from the o])ject, the less also becomes the
ditt"erence between tlie light of the surrounding atmos-
phere and that of the strata of air placed before the
niountain. For this reason, when summits of love
elevation begin to appear above the horizon, they are of
a darker tint than those more elevated ones which we
discover at very great distances. In like manner, the
vi-<ibility of mountains which are only negatively per-
ceived, does not depend solely upon the state of the low
regions of the air, to which our meteorological observa-
tions are confined, l)ut also upon its transparency and
phvbicul coubtitutiou in the most elevated parts ; for the


image is more distinctly detached, tlie more intense ihe chap. ir.

aerial lieht which comes from the limits of the atmos- , —

1 1 • • 11 1 111 •, 1 1 , . . Plienomeiis

pliere lias originally been, or the less it has lost in its of vision

passage. This in a certain degree accounts for the cir-
cumstance, that the Peak is sometimes visible and
sometimes invisible to navigators who are equally
distant from it, when the state of tlie thermometer and
hygrometer is precisely the same in the lower stratum
of air. It is even probable, that the chance of perceiving
this volcano would not be greater, were the cone equal,
as in Vesuvius, to a fourth part of the whole height.
The ashes spread upon its surface do not reflect so much Reflected
light as the snow with which the summits of the Andes ''gf't-
are covered, but, on the contrary, make the mountain,
when seen from a great distance, become more obscurely
detached, and assume a brown tint. They contribute,
as it were, to equalize the portions of aerial light, the
variable difference of which renders the object morf
or less distinctly visible. Bare calcareous mountains,
summits covered with granitic sand, and the elevated
savannahs of the Andes, which are of a bright yellow
colour, are more clearly seen at small distances than
objects that are perceived only in a negative manner ;
but theory points out a limit beyond which the latter
are more distinctly detached from the azure vault of the

The aerial light projected on the tops of hills increases projected
the visibility of those which are seen positively, but '^^'""^' ''^"''
diminishes that of such as are detached with a brown
colour. Bouguer, proceeding on theoretical data, has
found that mountains which are seen negatively cannot
be perceived at distances exceeding 121 miles ; but ex-
perience goes against this conclusion. The Peak of
Teneriffe has often been observed at the distance of
124, 131, and even 1.38 miles; and the summit of
Mowna-Roa in the Sandwich Isles, which is probably
10,000 feet high, has been seen, at a period when it was
destitute of snow, skirting the horizon from a distance
of 183 miles. This is the most striking example yet


CHAP. II. known of the visiljility of high land, and is the more
MdnT^f remarkable that the object was negatively seen,
lirund The atmosjjheie continuing hazy, tlie navigators did

"^^'' not discover the island of Grand Canary, notwithstanding

its height, until the evening of the IBtii June. On the
following day tliey saw the point of Naga, but the Peak
of TenerifFe still remained invisible. After repeatedly
sounding, on account of the thickness of the mist, they
ancliored in the road of Santa Cruz, when, at the moment
tliey began to salute the place, the fog instantaneously
dispersed, and the Peak of Teyde, illuminated by the
first rays of tlie sun, appeared in a break above the clouds.
Our travellers betook themselves to the bow of the vessel
to enjoy the majestic spectacle, when, at the very moment,
four Euglisli ships were seen close astern. The anchor
was immediately got up, and the Pizarro stood in as close
as possible, to i)lace herself under the protection of the
Dctcmii- While waiting tlie governor's permission to land,

luiifiiude. Humboldt employed the time in making observations
for determining the longitude of the mole of Santa Cruz
and the dip of the needle. Berthoud's chronometer gave
18° 33' 10", the accuracy of which result, altliougli dif-
fering from the longitude assigned by Cook and otliers,
was afterwards confirmed by Krusenstern, who found
tliat port IG^ 12' 45" west of Greenwich, and conse-
quently 18° 33' 0" west of Paris. The dip of the
magnetic needle was 62° 24', although it varied con-
siderably in different places along the shore. After
undergoing the fatigue of answering the numberless
questions proposed by persons who visited them on board,
our travellers were at lengtli permitted to land.



Island of Teneriffe.

Santa Cruz— -Villa de la Laguna — Guanches — Present Inhabitants
of'TenerifFe— Climate — Scenery of the Coast — Orotava — Dragon-
tree — Ascent of the Peak — Its Geological Character — Ernptions
— Zones of Vegetation — Fires of St John.

Santa Cruz, the Anaza of the Guanches, which is a chap. ni.
neat town with a population of 8000 persons, may be santa"ci-iu
considered as a great caravansera situated on the road to
America and India, and has consequently been often
described. The recommendations of the court of Madrid
procured for our travellers the most satisfactory recep-
tion in tlie Canaries. The captain-general gave per-
mission to examine the island, and Colonel Armiaga,
who commanded a regiment of infantry, extended his
hospitality to them, and showed the most polite attention.
In his garden they admired the banana, the papaw, and
other plants cultivated in the open air, which they had
before seen only in hothouses.

In the evening they made a botanical excursion to- Botanical
wards the fort of Passo Alto, along the basaltic rocks '^''cursion.
which close the promontory of Naga, but had little
success, as the drought and dust had in a manner de-
stroyed the vegetation. The Cacalia kleinia, Euphorbia
canariensis, and other succulent plants, which derive
their nourishment more from the air than from the soil,
reminded them by their aspect that the Canaries belong to
Africa, and even to the most arid part of that continent.



I. The captain of tlie Pizarro having apprized them that,
on account of the blockade by the Eiiglisli, they ought
^'■' - '^- not to reckon upon a longer stay than four or five days,

tliey hastened to set out for the port of Orotava, where
tliey might find guides for the ascent of the Peak ; and
on tile 20th, before sunrise, the}' were on the way to
Villa de la Laguna, which is 1684 feet above the sea.
The road to this place is on the right of a torrent which
rsnii-i, and in the rainy season forms beautiful falls. Near the town
liursL-s. ^j^p^^^ j^^p^ with some white camels employed in trans-

porting merchandise. These animals, as well as horses,
were introduced into the Canary Islands in the fifteenth
century by the Norman conr^uerors, and were unknown
to the Guanches. Camels are more abundant in Lan-
cerota and Forteventura, which are nearer the continent,
than at TenerifFe, where they very seldom propagate.
G>» The hill on which the Villa de la Laguna stands be-

longs to the series of basaltic mountains, which forms a
girdle around the Peak, and is independent of the newer
volcanic rocks. The basalt on which the travellers
walked was blackish-brown, compact, and partially de-
composed. Tliey found in it hornblende, olivine, and
transparent pyroxene, with lamellar fracture, of an
olive-green tint, and often crystallized in six-sided
prisms. The rock of Laguna is not columnar, but
divided into thin beds, inclined at an angle of from 30''
to 40°, and has no appearance of having been formed by
a current of lava from the Peak. Some arborescent
Kupliorbiip, Cacalia kleinia, and Cacti, were the only
jilants observed on these parched acclivities. The mules
blijtped at every step on the inclined surfaces of the rock,
althougli traces of an old road were observable, which,
with tlie numerous other indications that occur in these
colonies, afford evidence of the activity displayed by the
Spanish nation in the sixteenth century.
ii'.-it nf The heat of Siuita Cruz, which is suffocating, is in a

«^ '"-"^ great niejisure to be attributed to the reverberation of
the rocks in its vicinity ; but as the travellers approached
Lagnim they became sensible of a very pleasant dimi-

GUANCiirs. .30

niition of temperature. In fact, tlie perpetual coolness chap, ul
which exists here renders it a delightful residence. It LaKuua
is situated in a small plain, surrounded by gardens, and
commanded by a hill crowned with the laurel, tlie myrth',
and the arbutus. The rain, in collecting, forms from
time to time a kind of large pool or marsh, which has
induced travellers to describe the capital of TenerifFe as
situated on the margin of a lake. Tlie town, which was
deprived of its opulence in consequence of the port of
Garachico having been destroyed by the lateral erup-
tions of the volcano, has only 9000 inhabitants, of which
aliout 400 are monks. It is surrounded by numerous com wind-
windmills for corn. Humboldt observes, that the cereal "''"*•
grasses were known to the original inhabitants, and that
parched barley flour and goat's milk formed their prin-
cipal meals. This food tends to show that they were
connected with the nations of the Old Continent, perhaps
even with those of the Caucasian race, and not with the
inhabitants of the New World, who, previous to the
arrival of the Europeans among them, had no knowledge
of grain, milk, or cheese.

The Canary Islands were originally inhabited by Guanches.
a people famed for their tall stature, and knovvn by the
name of Guanches. They have now entirely disappeared
under the oppression of a more powerful and more en-
lightened race, which, assuming the superiority supposed
to be sanctioned by civilisation and the profession of the
Christian faith, disposed of the natives in a manner little
accordant with the character of a true follower of the
cross. The archipelago of the Canaries was divided Tiieir
into small states hostile to eacli other ; and in the M- ment.
teenth century, the Spaniards and Portuguese made
voyages to these islands for slaves, as the Europeans
have latterly been accustomed to do to the coast of
Guinea. One Guanche then became the property of
another, who sold him to the dealers ; while many,
rather than become slaves, killed their children and
themselves. The natives had been greatly reduced in
this manner, when Alonzo de Lugo completed their



rion of the


CHAP. III. sulijugation. The residue of that unhappy people
perished by a terrible pestilence in 1494, which was
supposed to have originated from the bodies left exposed
by the Spaniards after the battle of Laguna. At the
present day, no individual of pure blood exists in these
islands, where all that remains of the aborigines are
certain mummies, reduced to an extraordinary de-
gree of desiccation, and found in the sepulchral caverns
which are cut in the rock on the eastern slope of the
Peak. These skeletons contain remains of aromatic
plants, especially the Chenopodium ambrosioides, and are
often decorated with small laces, to which are suspended
little cakes of baked earth.

The people who succeeded the Guanches were de-
scended from the Spaniards and Normans. The present
inhabitants are described by our author as being of a
moral and religious character, but of a roving and
enterprising disposition, and less industrious at home
than abroad. The population in 1790 was 174,000.
The produce of the several islands consists chiefly of
wheat, barley, maize, potatoes, wine, a great variety of
fruits, sugar, and other articles of food ; but the lower
orders are frequently obliged to have recourse to the
roots of a species of fern. The principal ol)jects of
commerce are wine, brandy, archil (a kind of lichen
used as a dye), and soda.

TeneritfV- has been praised for the salubrity of its
climate. The ground of the Canary Islands rises gra-
dually to a great heiglit, and presents, on a small scale,
the temperature of every zune, from the intense heat of
Africa to the cold of the Alpine regions ; so that a
person may have the benefit of whatever climate' best
suits his temperament or disease, A similar variety
exists as to the vegetation ; and no country seemed to
our traveik-rs more fitted to dissipate nn lancholy, and
restore j)eHce to an agitated mind, than Teneriffe and
Madeira, where the natural l)eauty of the situation, and
the salubrity of the air, conspire to quiet the anxieties
ji tlie spirit and invigorate the body, while the feelings


arc not harassed by the revolting sight of slavery, which chap, hi
exists in almost all the European colonies.

In winter the climate of Laguna is excessively foggy, Winter
and the inhabitants often complain of cold, although ^"^^
snow never falls. The lowest height at which it occurs
annually in TenerifFe has not been ascertained ; but it
has been seen in a place lying above Esperanza de la
Laguna, close to the town of that name, in the gar-
dens of which the breadfruit-tree {^Artocarpus incisa),
introduced by M. Broussonet, has been naturalized. In
connexion with this subject, Humboldt remarks, that
in hot countries the plants are so vigorous that they can
bear a greater degree of frost than might be expected,
provided it be of short duration. The banana is culti-
vated in Cuba, in places where the thermometer some-
times descends to very near the freezing-point ; and in
Spain and Italy, orange and date trees do not perish,
although the cold may be nearly four degrees below
that point. Trees growing in a fertile soil are remarked
by cultivators to be less delicate, and less affected by
changes of temperature, than those planted in land that
affords little nutriment.

From Laguna to the port of Orotava, and the western western
coast of Teneriffe, the route is at first over a hilly "^'^^
country covered by a black argillaceous soil. The sub-
jacent rock is concealed by layers of ferruginous earth ;
but in some of the ravines are seen columnar basalts,
with recent conglomerates, resembling volcanic tufas
lying over them, which contain fragments of the former,
and also, as is asserted, marine petrifactions. This
delightful country, of which travellers of all nations
speak with enthusiasm, is entered by the valley of
Tacoronte, and presents scenes of unrivalled beauty.
The seashore is ornamented with palms of the date and Palm trees
cocoa species. Farther up, groups of muste and dragon-
trees present themselves. The declivities are covered
with vines. Orange-trees, myrtles, and cypresses, sur-
round the chapels that have been raised on the little
hills. The lands are separated by enclosures formed of


CHAP. iiL the agave and cactus. Multitudes of cryptogamic plants,
rian~ i-specially ferns, cover the walls. In winter, while tlie
volcano is wrajiped in snow, there is continued spring in
this beautiful ciistrict ; and in summer, towards evening,
the sea-breezes diffuse a gentle coolness over it. From
Teguestc and Tacoronte to the village of San Juan de la
Ranibla, the coast is cultivated like a garden, and might
lie compared to the neighbourliood of Capua or Valcntia ;
but tlie western part of Teneriffe is much more beautiful,
on account of the proximity of the Peak, the sight of
Volcanic which has a most imposing effect, and excites the ima-
action gination to penetrate into the mysterious source of

volcanic action. For thousands of years no light has
been observed at the summit of the mountain, and yet
enormous lateral eruptions, the last of which happened
in 1798, prove tlie activity of a fire wiiicli is far from
being extinct. There is, besides, something melancholy
in the sight of a crater placed in the midst of a fertile
and highly cultivated country.
Mantanza Pursuing their course to the port of Orotava, the

ai.J \-ittoiij. travellers passed the beautiful hamlets of Matanza and
Vittoria (slaughter and victory), — names which occur
together in all the Spanish colonies, and present a dis-
agreeable contrast to the feelings of peace and quiet
which these countries inspire. On their way they
Prfitanic visited a botanic garden at Durasno, where they found
Lu. jyj_ T^^ Gros, the French vice-consul, who subsequently

served as an excellent guide to the Peak. The idea of
forming such an establishment at TenerifFe originated
witli the Marquis de Nava, who thought that the Canary
Inlands afford the most suital)]e place for naturalizing
tlie j)lants of the East and West Indies, previous to
their introduction to Europe. They arrived very late
nt the port, and next morning commenced their journey
to the Peak, accompanied by M. Le Gros, M. Lalande,
secretary of the French consulate at Santa Cruz, the
English gardener of Dura-sno, and a numl)er of guides.
Orjur.. Orotava, the 'I'aoro of the Guanches, is situated on a

verv hteej) declivity, and lias a pleasant aspect wlien



CHAT, in

Drafcon-trec of Orotava.

viewed from a distance, although the houses, when seen DragoTitree.

at hand, have a gloomy appearance. One of the most

remarkable objects in this place is the dragon-tree in

the garden of M. Franqui, of which an engraving is here

presented, and which our ti'avellers found to be about

60 feet high, with a circumference of 48 feet near tlie

roots. Tlie trunk divides into a great number of

branches, which rise in the form of a candelabrum, and

are terminated by tufts of leaves. This tree is said to Great ape.

have been revered by the Guanches as the ash of Ephesus

was by the Greeks ; and in 1402, at the time of the

first expedition of Bethencour, was as large and as

hollow as our travellers found it. As the species is of

very slow growth, the age of this individual must be


Leaving Orotava, they passed by a narrow and stony
path through a beautiful wood of chestnuts to a place
covered with brambles, laurels, and arborescent heaths,



Ascent of
tlic peu'ii.


I maces of

fAee of tt

I. where, under a solitary pine, known by the name of
I'ino del Doinajito, they procured a supply of water.
From this place to the crater they continued to ascend
without crossing a single valley, passing over several
regions distinguished by their peculiar vegetation, and
rested during part of the night in a very elevated position,
where they suffered severely from the cold. About
three in the morning they began to climb the Sugar-
loaf, or small terminal cone, by the dull light of fir-
torches, and examined a small subterranean glacier or
cave, whence the towns below are supplied with ice
througliout the summer.

In tlie twilight they observed a phenomenon not
unusual on high mountains, — a stratum of white clouds
spread out beneath, concealing the face of the ocean, and
presenting the appearance of a vast plain covered with
snow. Soon afterwards another very curious sight
occurred, namely, the semblance of small rockets
thrown into the air, and which they at first imagined to
be a certain indication of some new erujjtion of the great
volcano of Laneerota. But the illusion soon ceased,
and they found that the luminous points were only the
images of stars magnified and refracted by the vapours.
They remained motionless at intervals, then rose per-
pendicularly, descended sidewise, and returned to their
original position. After three hours' march over an
extremely rugged tract, the travellers readied a small
))lain called La Kambleta, from the centre of which
rises the Piton or Sugar-loaf. The slope of this cone,
covered with volcanic ashes and pumice, is so steep that
it would have been almost impossible to reach the
summit, had they not ascended by an old current of
lava, wliicli had in some measure resisted the action of
the atmosphere.

ic On attaining the top of this steep, they found them-
selves on the edge of the crater, from whicli they de-
s<'ended to the bottom of the funnel or caklera, the
tjreatcst diameter of wliich at the mouth seimed to be
020 feet. There were no large openings in the crater ;


hut aqueous vapours were emitted by some of the ere- chap. mi.

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