Alexander von Humboldt.

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cowhouse, from wlucli he was led to prison. The in-



REMARKABLE ATMOSPHERIC PHENOMENA. 107

habitants showed the warmest concern for the strangers, chap. X.

and although Bonpland had a fever during the night he

speedily recovered. The object of the Zambo, who soon
afterwards succeeded in escaping from the castle of San
Antonio, was never satisfactorily made out.

Notwithstanding this untoward accident Humboldt Eclipse of
was enabled to observe the eclipse. The days which ^'^ '*^"-
preceded and followed it displayed very remarkable
atmospheric phenomena. It was what is called Avinter
in those countries. From the 10th of October to the
Sd of November a reddish vapour rose in the evening,
and in a few minutes covered the sky. The hygrometer
gave no indication of humidity. The diurnal heat was
from 82'4° to 89'6°. Sometimes in the midst of the
night the mist disappeared for a moment, when clouds Atmospheric
of a brilliant whiteness formed in the zenith, and ex- phenomena.
tended towards the horizon. On tlie 18th of October
they were so transparent that they did not conceal stars
even of the fourth magnitude, and the spots of the moon
were very clearly distinguished. They were arranged
in masses at equal distances, and seemed to be at a pro-
digious height. From the 28th of October to the 3d of
November the fog was thicker than it had yet been.
The heat at night was stifling, althougli the thermometer
indicated only 78'8'. The evening breeze was no longer
felt ; the sky appeared as if on fire, and the ground was
every where cracked and dusty. On the 4th of Novem-
ber, about two in the afternoon, large clouds of extra- „ i t,i
ordmary blackness enveloped the mountams of the clouds.
Brigantine and Tataraqual, extending gradually to the
zenith. About four, thunder was heard overhead, but
at an immense height, and with a dull and often inter-
rupted sound. At the moment of the strongest electric
explosion, two shocks of an earthquake, separated by an
interval of fifteen seconds, were felt. The people in the r;„jrt,„najjQ_
streets filled- the air with their cries. Bonpland, who
was examining plants, was nearly thrown on the floor,
and Humboldt, who was lying in his hammock, felt the
concussion strongly. Its direction was from north to



108



EARTHCIUAKE.



Setting sun.



Tbird shock.



CHAP. X. south. A few minutes before the first, there was a
violent gust of wind followed by large drojos of rain.
The sky remained cloudy, and the blast was succeeded
by a dead calm which continued all night. Tlie setting
of the sun presented a scene of great magnificence. Tiie
dark atmospheric shroud was rent asunder close to the
horizon, and the sun appeared at ]2° of altitude on an
indigo ground, its disk enormously enlarged and distorted.
The clouds were gilded on the edges, and bundles of
rays reflecting the most brilliant prismatic colours ex-
tended over the heavens. Al)out nine in the evening
there was a third shock, which, although much slighter,
was evidently attended with a subterranean noise. The
barometer was a little lower tban usual, but the pro-
gress of the horary variations was in no way interrupted.
In the night, between the 8d and 4th of November, the
red vapour was so thick that the jjlace of the moon
could be distinguished only by a beautiful halo, 20' in
diameter.

Scarcely twenty-two months had elapsed since the
almost total destruction of Cumana by an earthquake ;
and as tlie people look on the vapours, and tlie failure
of the breeze during the night, as prognostics of disaster,
the travellers had frequent visits from persons desirous
of knowing whether their instruments indicated new
shocks on the morrow. On the 5th, precisely at the
same liour, the same phenomena recurred, but without
any agitation ; and the gust accompanied by thunder
returned periodically for five or six days.

This earthquake, being the first tiiat Humboldt ever
felt, made a strong impression upon him ; l)ut scenes of
this kind afterwards became so familiar as to excite
little apprehension. It appeared to have a sensible
influence on the niagnetical phenomena. Soon after his
arrival on tlie coasts of Cumana, he found the dip of the
needle 48-53° of the centesimal division. On the 1st of
November it was 43-65°. On the 7th, three days after
the concussion, lie was astonished to find it no more
than 42-75'^, or 90 centesimal minutes less. A year



Popular iip-
prehensioiL



Impression
on H lira-
bold L



LUMINOUS METEORS. 109

later, on his return from the Orinoco, he still found it chap. X.
42-80°, though the intensity of the magnetic forces jiarrj^c
remained the same after as before the event under con- piicnomena.
sidcration, being expressed by 229 oscillations in ten
minutes of time. On the 7th November he observed
the magnetic variation to be 4° 13' 50" E.

The reddish vapour which appeared about sunset jieteora.
ceased on the 7th of November. The atmosphere then
assumed its former purity ; and the night of the 11th
was cool and extremely beautiful. Towards morning a
very extraordinary display of luminous meteors was
observed in the east by M. Bonpland, who had risen to
enjoy the freshness of the air in the gallery. Thousands
of fire-balls and falling-stars succeeded each other during
four hours, having a direction from north to south, and course of
filling a space of the sky extending from the true east fire-baUs.
30 degrees on either side. They rose above the horizon
at E.N.E. and at E., described arcs of various sizes, and
fell toward S., some attaining a height of 40°, and all
exceeding 25° or 30°. No trace of clouds was to be
seen, and a very slight easterly wind blew in the lower
regions of the atmosphere. All the meteors left lumi-
nous traces from five to ten degrees in length, the phos-
phorescence of which lasted seven or eight seconds.
The fire-balls seemed to explode, but the largest disap-
peared without scintillation ; and many of the falling-
stars had a very distinct nucleus, as large as the disk of
Jupiter, from which sparks were emitted. The light L;o-i;t,
occasioned by them was white, — an effect which must
be attributed to the absence of vapours ; stars of the
first magnitude having, within the tropics, a much paler
hue at their rising than in Europe.

As the inhabitants of Cumana leave their houses
before four to attend the first morning mass, most of
them were witnesses of this phenomenon, which gra-
dually ceased soon after, although some were still
perceived a quarter of an hour after sunrise.

The day of the 12th November was exceedingly hot,
and in the evening the reddish vapour reappeared in the



110



LUMINOUS METEORS.



Ilesearches
regarding
tlie meteors



CHAP. X. horizon, and rose to the height of 14°. This was the
last time it was seen that year.

The researches of M. Chladni having directed the
attention of the scientific world to fire-balls and falling-
stars at the period of Humboldt's departure from home,
he did not fail to inquire, during his journey from
Caraccas to the Rio Negro, whether the meteors of the
12th November had been seen. lie found that they
had been observed by various individuals in places very
remote from each other ; and on returning to Europe
was astonished to find that they had been seen there
also. The following is a brief account of the facts
relating to these phenomena: — 1st, The luminous me-
Facts noted, teors were seen in the E. and E.N.E. at 40° of elevation,
from two to six a.m., at Cumana, in lat 10^ 27' 52",
long. 64° 10' ; at Porto Cabcllo, in lat. 10° 6' 62", long.
64° 45' ; and on the frontiers af Brazil, near the equator,
in long. 67° 40' west. 2dly, The Count de jNIarbois
observed them in French Guiana, lat. 4° 50', long. 62°
15'. 3dly, Mr Ellicot, astronomer to the United States,
being in the Gulf of Florida on the 12th November,
saw an immense number of meteors, some of wliich
appeared to fall perpendicularly ; and the same pheno-
menon was perceived on the American continent as far
as lat. 30° 42'. 4thly, In Labrador, in lat. 50° 55', and
lat. 58° 4'; in Greenland, in latitudes 61° 5' and 64°
14', the natives were frightened by the vast quantity of
fire-balls that fell during twilight, some of them of
great size. 6thly, In Germany, Mi- Zeissing, vicar of
Itterstadt near Weimar, in lat. *50° 59', long. 11° 21' E.,
observed, between six and seven in the morning of the
12th November, some falling-stars having a very white
light. Soon after reddish streaks ajjpeared in the S.
and S.W. ; and at dawn the south-western part of the
sky was from time to time illuminated by white light-
ning running in serpentine lines along the horizon.

Calculating from these facts, it is manifest that the
height of the meteors was at least 1419 miles ; and, as
near AVcimar they were seen in the S. and S.W., while



CiilcalatioQS.



LUMINOUS METEORS. Ill

at Cumana they were observed in the E. and N.E., we CHAP. X.

must conclude that they fell into the sea between
Africa and South America, to the west of the Cape
Verd Islands.

Without entering into the learned discussion, which Fnrtiiev
Humboldt submits to his readers, respecting the nature oMervations.
of these luminous bodies, we shall merely observe, that
he found falling-stars more frequent in the equinoctial
regions than in the temperate zone, and also that they
occurred oftener over continents and near certain coasts
than on the ocean. He states that on the platform ot
the Andes there was observed, upwards of thirty years
before, a phenomenon similar to that related above as
having occurred at Cumana. From the city of Quito
an immense number of meteors was seen rising over the
volcano of Cayambo, insomuch that the whole mountain
was thought to be on fire. They continued more than
an hour, and a religious procession was about to be
commenced, when the true nature of the luminous
appearance was discovered.



112 DEPARTUKE FROM CUMANA,



CHAPTER XL

Voyage from C'umana to Guayra.

e from Cumana to La Guayra — Phosphorescenco of the Sea —
Group of the Caraccas and Chinianas — Port of New Barcelona —
La Guayra — Yellow fever — Coast and Cape Blanco — Road from
La Guayra to Caraccas.

CHAP. XI. Having completed the partial investigations which their

rreparations short residence admitted, and having in some measirre

for kaviiig become acclimatized, the adventurous piiilosophers pre-

"^^'"'■^ pared to leave Cumana. Passing by sea to La Guayra,

they intended to take up their abode in the town of

Caraccas until the rainy season should be over ; from

thence to traverse the Llanos, or great plains, to the

missions of the Orinoco ; to go up that river as far as

the Rio Negro ; and to return to Cumana by Angostura,

tlie capital of Spanish Guiana.

Dortutuic On the 18th November, at eight in the evening, they

took their passage in one of the boats which trade

between these coasts and the West India Islands, They

arc thirty-two feet long, three feet high at the gunwale,

without decks, and generally carry from 200 to 250

quintals (181 to 226 cwts. avoirdupois). Although the

sea is very rough from Cape Codera to La Guayra, and

these boats have an enormous triangular sail, there liad

not been an instance for thirty years of tlie loss of one of

tliem on the passage from Cumana to Caraccas, so great

is the skill of the Guayqueria pilots. They descended

the Manzanares witli rajiidity, delighted witli the sight

- of its marginal cocoa-trees, and the glitter of the thorny



PHOSPHORESCENCE OF THE SEA. 1 15

I)ushes covered with noctilucous insects, and left with chap. XL

regret a country in which every thing had appeared ^ .

new and marvellous. Passing at high water the bar of tiie Man-
t]ie river, they entered the Gulf of Cariaco, the surface ^""^'"^*-
of which was gently rippled by the evening breeze. In
a short time the coasts were recognised only by the
scattered lights of the Indian fishermen.

As they advanced toward the shoal that surrounds c.^pe Arenas.
Cape Arenas, stretching as far as the petroleum springs
of Maniquarez, they enjoyed one of those beautiful
sights which the phosphorescence of the sea so often
displays in tropical climates. When tlie porpoises,
which followed the boat in bands of fifteen or sixteen,
struck the surface of the Avater witli their tails, they
produced a brilliant light resembling flames. Each
troop left behind it a luminous track ; and as few sparks
were caused by the motion of an oar or the track of the
l)oat, Humboldt conjectured that the vivid glow pro-
duced by these cetaceous animals was owing not to the
stroke of their tails alone, but also to the gelatinous
matter which envelops their bodies, and which is
detaclied by the waves.

At midnight they found themselves among some .j.,,^ carace.is
rocky islets, rising in the form of bastions, and consti- and ciii-
tuting the group of the Caraccas and Chimanas. Many "'^"'"'
of these eminences are visible from Cumana, and pre-
sent the most singular appearances under the effect of
mirage. Their heiglit, wliich is probably not more
tiian 960 feet, seemed much greater when enlightened
I)y the moon, wliich now shone in a clear sky. Tlie
travellers were becalmed in the ncighbourliood of these
islands, and at sunrise drifted towards Boracha, the j^pj.pjjj.p^
largest of them. The temperature had sensibly in- teiDperature.
creased, in consequence of the rocks giving out by
radiation a portion of the heat which they had absorbed
during the day. As tlie sun rose, the cliffs projected
their lengthened shadows upon tlie ocean, and the
flamingoe? began to fish in the creeks. These insular
spots were all uninhabited ; but on one of them, which



] IG MOKRO DE BARCELONA.

CHAP. XI. had formerly been the residence of a family of whites,
wudKoats there were wild goats of a large size and brown colour.
The inhabitants had cultivated maize and cassava ; but
the father, after the death of his children, having pur-
chased two black slaves, was murdered by them. One
of the assassins subsequently informed against his accom-
plice, and at the time of Humboldt's visit was hangman
at Cumana.
New Uai- Proceeding onwards they anchored for some hours in

celuna. ^j^^ ^^^ ^£ -^^^ Barcelona, at the mouth of the river

Neveri, which is full of crocodiles. These animals,
especially in calm weather, occasionally make excursions
into the open sea, — a fact which is interesting to
geologists, on account of the mixture of marine and
fresh-water organic remains that are occasionally ob-
Commerce of served in some of the more recent deposites. The port
tue port. ^£ Barcelona had at that time a very active commerce,
arising from the demand in the West Indies for salted
• provision, oxen, mules, and liorses ; the merchants of
the Havannah being the principal purchasers. Its
situation is extremely favourable for this exportation,
the animals arriving in three days from the Llanos,
while they take more than double that time to reach
Cumana, on account of the chain of mountains which
they liave to cross. Eiglit thousand mules were em-
l)arked at Barcelona, six thousand at Porto Cabcllo, and
three thousand at Carupano, in 1799 and IHOO, for tlie
several islands.
Morro d^^ Landing on the right bank of the river, they ascended

baiceu.aa. jg ^ g,„jjji j-^^^^ ^lie Morro de Barcelona, built on a
calcareous rock, at an elevation of about 400 feet above
the sea, but commanded by a mucli higher hill on the
south. Here tiicy observed a very curious geological
phenomenon, which recurred in the cordilleras of Mex-
ico. The limestone, which had a dull, even, or flat
conchoidal fracture, and was divided into very thin
strata, was traversed by layers of black slaty jasper,
with a similar fracture, and breaking into fragmeniij
liaving a parallelopipedal form. It did not exhibit the



MANGROVES. 1 1 "]

little veins of quartz so common in Lj'dian stone, and CHAP. XI.

was decomposed at the surface into a yellowish-gray

crust.

Setting sail on the 19th at noon, they found the tem- Tcmperamru
perature of the sea at its surface to be 78'6° ; but when "* "^"^ ""^
passing through the narrow channel which separates the
Piritoos, in three fathoms it was only 76-1°. These
islands do not rise more than eight or nine inches above
the mean height of the tide, and are covered with long
grass. To the westward of the Morro de Barcelona and
the mouth of the river Unare, the ocean became more and
more agitated as they approached Cape Codera, the
influence of which extends to a great distance. Beyond
this promontory it always runs very high, althougli a
gale of wind is never felt along this coast. It blew
fresh during the night, and on the 20th, at sunrise, they
were so advanced as to be in expectation of doubling the
Cape in a few hours ; but some of the passengers having
suffered from sea-sickness, and the pilot being apprehen-
sive of danger from the priv'ateers stationed near La
Guayra, they made for the shore, and anchored at nine
o'clock in the Bay of Iliguerota, westward of the Rio
Capaya.

On landing, they found two or three huts inhabited g^., ^j
by mestizo fishermen, the livid tint of whom, together Iliguerota.
with the miserable appearance of their children, gave
indication of the unhealthy nature of the coast. The
sea is so shallow that one cannot go ashore in the
smallest boat without wading. The woods come nearly
to the beach, which is covered with mangroves, avicen-
nias, manchineel-trees, and Suriana maritima, called by
the natives romero de la mar. Here as elsewhere the
insalubrity of the air is attributed to the exhalations
from the first of these plants. A faint and sickly smell
was perceived, resembling that of the galleries of
deserted mines. The temperature rose to 93-2°, and
the water along the whole coast acquired a yellowish-
brown tint wherever it was in contact with these trees.

Struck by this phenomenon, Humboldt gathered a



118 LOAV SHORES OF TIlOl'ICAL REGIONS.

CHAP. XI. considerable quantity of brandies and roots with the
Tiienrui ^^*^^^' ^^ making experiments on the mangrove upon his
fe'iove. arrival at Caraccas. Tlie infusion in warm water was of a

brown colour, and had an astringent taste. It contained
extractive matter and tannin. When kept in contact
witli atmospheric air under a glass jar for twelve days,
the purity of tlie latter was not perceptibly affected.
The wood and roots placed under water were exposed to
]\x]H'n. tlie rays of the sun. Bubbles of air were disengaged,
uicuu. which at the end of ten days amounted to a volume of

40 cubic inches. These consisted of azote and carbonic
acid, with a trace of oxygen. Lastly, the same sub-
stances thoroughly wetted were enclosed with a given
volume of atmospheric air in a phial. The whole of the
oxygen disappeared. These experiments led him to
think that it is the moistened bark and fibre that act
upon the atmosphere, and not the brownish water which
formed a distinct belt along the coast. Many travellers
attribute the smell perceived among mangroves to the
disengagement of sulphuretted hydrogen ; but no ap-
pearance of this kind was observed in the course of
these investigations.
ohseiv.it inns " Besides," says Humboldt, " a thick wood covering a
of iiumboiat. muddy ground would diffuse noxious exhalations in the
atmosphere, were it composed of trees which in them-
selves have no deleterious property. Wherever man-
groves grow on the margin of the sea, the beach is
peopled with multitudes of mollusca and insects. These
animals prefer the shade and a faint light ; and find
shelter from the waves among the closely interlaced
roots which rise like lattice-work above the surface of
the water. Shells attach tliemselves to the roots, crus-
taceous animals nestle in the hollow trunks, the sea-
weeds which the wind and tide drive upon the shore re-
main hanging upon the recurved brancdies. In this
manner the maritime forests, by accumulating masses of
mud among their roots, extend the domain of the con-
tinents ; but, in proportion as they gain u])on the sea,
ihey scarcely experience any increase in breadth, their



CAPE CODKIIA. 119

very progress becoming the cause of their destruction, chap. xi.
The mangroves and the other plants with wliicli they jfan^i^o
always associate die as the ground dries, and when the forests,
salt water ceases to bathe them. Centuries after, their
decayed trunks, covered with shells, and half buried in
the sand, mark both the route which they have followed
in their migrations, and the limit of the land which they
have wrested from the ocean."

Cape Codera, seven miles distant from the bay of cape
Iliguerota, is more imposing on account of its mass than Codeia.
for its elevation, which appeared to be only 1280 feet.
It is precipitous on the north, west, and east. Judging
from the fragments of rock found along the coast, and
from the hills near the town, it is composed of foliated
gneiss, containing nodules of reddish felspar, and little
quartz. The strata next the bay have the same dip and
direction as the great mountain of the Silla, which
stretches from Caraccas to Maniquarez in the Isthmus
of Araya, and seem to prove that the primitive chain
forming that neck of land, after being disruptured or
swallowed up by the sea along an extent of 1 21 miles,
reappears at Cape Codera, and runs westward in an
unbroken line. Toward the north the cape forms an
immense segment of a sphere, and at its foot stretches a
tract of low land, known to navigators by the name of
the Points of Tutumo and of San Francisco.

The passengers In the boat dreaded the rolling in a ciiange of
rough sea so much that they resolved to proceed to plans.
Caraccas by land, and M. Bonpland, following their
example, procured a rich collection of plants. Hum-
boldt, however, continued the voyage, as it seemed
hazardous to lose sight of the instruments.

Setting sail at the beginning of the night, they English
doubled Cape Codera with difficulty, the wind being frigate.
unfavourable, and the surges short and high. On the
21st of November, at sunrise, they were opposite Curuao,
to the west of the cape. The Indian pilot was fright-
ened at seeing an English frigate only a mile distant ;
but they escaped without attracting notice. The raoun-



120



ARRIVAL AT LA GCAYRA.



Anival at
Curuccas.



CHAP. XI. tains were every where precipitous, and from 8200 to
Precipitous 4300 feet liigli, while along the shore was a tract of low
Biuuntains. huniid land, glowing with verdure, and producing a
great part of tlie fruits found so abundantly in the
neighbouring markets. The peaks of Niguatar and the
Silla of Caraccas form the loftiest summits of this chain.
In the fields and valleys the sugar-cane and maize are
cultivated. To the west of Caravalleda the declivities
along shore are again very steep. After passing this
place they discovered the village of Macuto, the black
rocks of La Guayra covered with batteries, and in the
distance the long promontory of Cape Blanco, with
conical summits of dazzling whiteness.

Humboldt landed at Guayra, and in the evening
arrived at Caraccas, four days sooner than his fellow-
travellers, who had suffered greatly from the rains and
inundations. The former he describes as rather a road
tlian a port, the sea being always agitated, and ships
suffering from the action of the wind, the tideways, the
bad anchorage, and the worms. The lading is taken in
with difficulty. The free mulattoes and negroes, who
carry the cocoa on board the ships, are remarkable for
their strength. They go througli the water up to tlieir
middles, although this place abounds in sharks, from
which, however, they have in reality nothing to dread.
It is singular, that while these animals are dangerous
and bloodthirsty at the island opposite the coast of
Caraccas, at the Roques, at Buenos Ayres, and at
Curassao, they do not disturb persons swimming in the
ports of Guayra and Santa Martha. As an analogous
fact, Humboldt mentions that the crocodiles of one pool
in the Llanos are cowardly, while those of another
attack with the greatest fierceness.

The situation of La Guayra resembles that of Santa
Cruz in Teneriffe ; the houses, which are built on a flat
piece of ground about G40 feet broad, being backed by a
wall of rock, beyond which is a chain of mountains.
The town consists of two parallel streets, and contains
COOO or 8000 inhabitants. The heat is greater than



Sharks.



L:i Guayia.



YELLOW FEVER. 121

even at Cumaiia, Porto Cabello, or Core, the sea-breeze CHAP. XL



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