Alexander von Humboldt.

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Temperature of the ^j>.— In the basin of the northern
AtlaJitic Ocean, between the coasts of Europe, Africa,
and America, the temperature of the atmosphere exhi-


bits a very slow increase. From Corunna to the cmvp. iv
Canary Islands, the thermometer, observed at noon, and
in the shade, gradually rose from 50° to 64°, and from
TenerifFe to Cumana from 64° to 77°. The maximum
of heat observed during the voyage did not exceed 79*9°.

The extreme slowness with which the temperature Oradnai
increases during a voyage from Spain to South America ^ '""^es.
is highly favourable to the health of Europeans, as it
gradually prepares them for the intense heat which
they have to experience. It is in a great measure
attributable to the evaporation of the water, augmented
by the motion of the air and waves, together with the
property possessed by transparent liquids of absorbing
very little light at their surface. On comparing the
numerous observations made by navigators, we are
surprised to see that in the torrid zone, in eitlier hemi-
sphere, they have not found the thermometer to rise in
the open sea above 93° ; while in corresponding latitudes
on the continents of Asia and Africa, it attains a much
greater elevation. Tlie difference between the tempera-
ture of the day and night is also less than on land.

Temperature of the Sea. — From Corunna to the mouth Tempera-
of the Tagus, the temperature of the sea varied little '""'® "^ ^*'*'
(between 59° and 60-8°) ; but from lat. 39° to 10° N.,
the increase was rapid, and generally uniform (from 59°
to 78'4°), although inequalities occurred, probably
caused by currents. It is very remarkable, that there
is a great uniformity in the maximum of heat every
where in the equinoctial waters. This maximum,
which varies from 82° to 84-2°, proves that the ocean is
in general warmer than the atmosphere in direct contact
with it, and of which the mean temperature near the
equator is from 78*8° to 80-6°.

Hygrometrical State of the Air. — During the whole of HyCTo-
the voyage, the apparent humidity of the atmosphere ^'^['^of .ij.
indicated by the h3'grometer underwent a sensible in-
crease. In July, in lat. 13° and 14° N., Saussure's
hygrometer marked at sea from 88° to 92°, in perfectly
clear weather, tlie thermometer being at 75-2°. On the



banks of the Lake of Geneva the mean Immidity of the
same month is only 80*^, the average heat being G6"2°.

iiuinidity On reducing these observations to a uniform temperature,
we lind that the real humidity in the equinoctial basin
of the Atlantic Ocean is to that of the summer months
at Geneva as 12 to 7. This astonishing degree of mois-
ture in the air accounts to a great extent for the
vigorous vegetation which presents itself on the coast
of South America, where almost no rain falls during
many years.

Intensity Intensity of the Colour of the Sky and Ocean. — From

?i ^'."'"" the coasts of Spain and Africa to those of South America,
the azure colour of the sky increased from 13^ to 23° of
Saussure's cyanometer. From the 8th to the 12th of July,
in lat. 12.',° and 14° N., the sky, although no vapour
could be observed, was of an extraordinary paleness, the
instrument indicating only 16° or 17°, although on the
preceding days it had been at 22°. The tint of the sky
is generally deeper in the torrid zone than in high lati-
tudes, and in the same parallel it is fainter at sea than
on land. The latter circumstance may be attributed to
the quantity of aqueous vapour which is continually
rising towards tlie higher regions of the air from the
surface of the sea. From the zenitli to the horizon, there
is in all latitudes a diminution of intensity, which follows
nearly an arithmetical progression, and depends upon the
moisture suspended in the atmosphere. If the cyano-
meter indicate this accumulation of vapour in the more
elevated portion of the air, the seaman possesses a simpler
method of judging of the state of its lower regions, by

So'ioj dib'i observing the colour and figure of the solar disk at its
rising and setting. In the torrid zone, where meteoro-
logical ])henoniena followeach other witli great regularity,
the prognostics are more to be depended upon than in
nortliern regions. Great paleness of the setting sun,
and an extraordinary disfiguration of its disk, almost
certainly pre&ige a storm ; and yet one can hardly con-
ceive iiow tlic condition of the lower strata of the air,
which is announced in this manner, can be so intimately


conpectcd with those atmospherical changes that take chap, iv
place after eight or ten hours.

Mariners, are accustomed to observe the appearances Ji;>riners
of the sky more carefully tlian landsmen, and among cat^is! ''
the numerous meteorological rules which pilots transmit
to each other, several evince great sagacity. Prognostics
are also in general less uncertain on the ocean, and
especially in the equinoctial parts of it, than on land,
where the inequalities of the ground interrupt the re-
gularity of their manifestation.

Humboldt also applied the cyanometer to measure Colo-ar of
the colour of the sea. In fine calm weather, the tint ^^^
was found to be equal to 33°, 38°, sometimes even 44°
of the instrument, although the sky was very pale, and
scarcely attained 14^ or 15°. When, instead of directing
the apparatus to a great extent of open sea, the observer
fixes his eyes on a small part of its surface viewed
through a narrow aperture, the water appears of a rich
ultramarine colour. Towards evening again, when the
edge of the waves, as the sun shines upon them, is of an
emerald-green, the surface of the shaded side reflects a
purple hue. Nothing is more striking than the rapid Rapid
changes which the colour of the sea undergoes under a -^'^^'ises-
clear sky, in the midst of the ocean and in deep water,
when it may be seen passing from indigo-blue to the
deepest green, and from this to slate-gray. The blue is
almost independent of the reflection of the atmosphere.
The intertropical seas are in general of a deeper and
purer tint than in high latitudes, and the ocean often
remains blue, when, in fine weather, more than four-
fifths of the sky are covered with light and scattered
clouds of a white colour.




Landing at Cumana — Introduction to the Governor — State of the
Sick — Description of the Country and City of Cumana— Mode of
Bathini^ in the Manzanares — Port of Cumana — Earthquakes ;
Their Periodicity ; Connexion with the State of the Atmosphere;
Gaseous Emanations; Subterranean Noises; Propajjation of
Shocks; Connexion between those of Cumana and the West In-
dies ; and General Phenomena.

CHAP. V The city of Cumana, the capital of New Andalusia, is a
C:t)'^f~ mile distant from the landing-place, and in proceeding
Cumana. towards it our travellers crossed a large sandy plain,
which separates the suburb inhabited by the Guayqueria
Indians from the seashore. The excessive heat of the
atmosphere was increased by the reflection of the sun's
rays from a naked soil, the thermometer immersed in
which rose to 99 •0°. In the little pools of salt water it
remained at 86'9°, while the surface of the sea in the
port generally ranges from 77"4° to 79'3'^. The first
plant gathered by them was the Avicennia tomentosa,
which is remarkable for occurring also on the Malabar
coast, and belongs to the small number that live in so-
ciety, like the heaths of Europe, and are seen in the
torrid zone only on the shores of the ocean and the ele-
vated platforms of the Andes.
Don Vicente Crossing the Indian suburb, the streets of which were
mparau. ^,^^^, j^^,^^^^ ^]^^y ^^.^^.^ conducted by the captain of the
I'izarro to the governor of the province, Don Vicente
Emparan. who received them with frankness ; expressed


his satisfaction at the resolution which they had taken chap. V.
of remaining for some time in New Andalusia ; showed j, ~T"
them cottons dyed with native plants, and furniture
made of indigenous wood ; and surprised them with
questions indicative of scientific attainments. On dis-
embarking their instruments, they had the pleasure of
finding that none of them had been damaged. They
hired a spacious house in a situation favourable for as-
tronomical observations, in which they enjoyed an agree-
able coolness when the breeze arose, the windows being
without glass, or even the paper panes which are often
substituted for it at Cumana.

The passengers all left the vessel. Those who had Recovery of
been attacked by the fever recovered so very slowly, ^^^ ^'^^
that some were seen a month after, who, notwithstanding
the care bestowed upon them by their countrymen,
were still in a state of extreme debility. The hospitality
of the inhabitants of the Spanish colonies is such that
the poorest stranger is sure of receiving the kindest
treatment. Among the sick landed here was a negro, Death of a
who soon fell into a state of insanity and died ; which negra
fact our author mentions, as a proof that persons Lorn
in the torrid zone are liable to suffer from the heat of
the tropics after having resided in temperate climates.
This individual, who was a robust young man, was a
native of Guinea, but had lived for some years on the
elevated plain of Castile.

The soil around Cumana is composed of gypsum and c,p;| ^^^
calcareous breccia, and is supposed at a remote period to plants.
have been covered by the sea. The neighbourhood of v
the city is remarkable for the woods of cactus which are
spread over the arid lands. Some of these plants were
thirty or forty feet high, covered with lichens, and di-
vided into branches in the form of a candelabrum.
When the large species grow in groups they form a
thicket which, while it is almost impenetrable, is ex-
tremely dangerous on account of the poisonous serpents
that fiisquent it.

The fortress of St Antonio, which is built on a calcar-


CHAP. V eous hill, commands the town, and forms a picturesqus

,. , ohiect to vessels entcrinirtlie port. On the south-western

st^Viitonio slope of the same rock are the ruins of the castle of St
Mary, from the site of which there is a fine view of the
Gulf, together with the island of Margarita and the
small isles of Caraccas, Picuita, and Boracha, which
present the most singular appearances from the effect of
Site of the "^^^^ ^^^Y °^ Cumana, properly speaking, occupies the
city. ground that lies between the castle of St Antonio and

the small rivers IManzanares and Santa Catalina. It
has no remarkable buildings, on account of the violent
earthquakes to which it is subject. The suburbs are
almost as populous as the town itself, and are three in
number : namely, Serritos, St Francis, and that of the
Guayquerias. The latter is inhaluted by a tribe of
civilized Indians, who, for upwards of a century, have
adopted the Castiiian language. The whole populatior
in 1802 was about eighteen or nineteen thousand.
Surronndini; The plains wliicli surround the city have a parched
country. and dusty aspect. The hill on wliich the fort of St
Antonio stands is also bare, and composed of calcareous
breccia, containing marine shells. Southward, in the
distance, is a vast curtain of inaccessible mountains, also
of limestone. These ridges are covered by majestic
forests, extending along the sloping ground at tluir base
to an open plain in the nciglibourhood of Cumana,
through which the river Manzanares winds its way to
the sea, fringed with mimosas, erythrinas, ceibas, and
other trees of gigantic growth.
RivorMan- This river, tlie temperature of -which in the season of
the floods descends as low as 71 '6'', when that of the air
is as high as OT, is an inestimable benefit to the inhabi-
tants ; all of whom, even the women of the most opu-
lent families, learn to swim. Tlie mode of bathing is
various. Our travellers frequented every evening a
very respectalilc society in the suburb of the Guay-
querias. In the beautiful moonlight, chairs were placed
in the water, on which were seated the ladies and



gentlemen, lightly clothed. The family and the stran- CHAp. v.
gers passed several hours in the river, smoking cigars Native
and chatting on the usual subjects of conversation, such pas'imes.
as tlie extreme drought, tlie abundance of rain in the
neighbouring districts, and the female luxuiy which
prevails in Caraccas and Ilavannah. The company
were not disturbed by the bavas, or small crocodiles,
which are only three or four feet long, and are now
extremely rare. Humboldt and his companions did not
meet with any of them in the Manzanares ; but they
saw plenty of dolphins, which sometimes ascended the
river at night, and frightened the bathers by spouting
water from their nostrils.

The port of Cumana is capable of receiving all the Tort of
navies of Europe ; and the whole of the Gulf of Cariaco,
which is forty-two miles long and from seven to nine
miles broad, affords excellent anchorage. The hurricanes
of the West Indies are never experienced on these coasts,
where the sea is constantly smooth, or only slightly
agitated by an easterly wind. The sky is often bright
along the shores, while stormy clouds are seen to gather
among the mountains. Thus, as at the foot of the
Andes, on the western side of the continent, the extremes
of clear weather and fogs, of di-ought and heavy rain, of
absolute nakedness and perpetual verdure, present them-
selves on the coasts of New Andalusia.

The same analogy exists as to earthquakes, which are Frequency of
irequent and violent at Cumana. It is a generally-
received opinion that the Gulf of Cariaco owed its
existence to a rent of the continent, the remembrance
of which was fresh in the minds of the natives at the
time of Columbus' third voyage. In 1530, the coasts
of Paria and Cumana were agitated by shocks ; and
towards the end of the sixteenth century, earthquakes
and inundations very often occurred. On the 21st
October 17C6, the city of Cumana was entirely destroyed
in the space of a few minutes. Tlie earth opened in
several parts of the province, and emitted sulphureous
waters. During the years 1766 and 1767, the inhabi-




of tbe city.




tants encamped in the streets, and tliey did not begin to
rebuild tbeir liouses until tbe earthquakes took place
only once in four weeks. These commotions had been
preceded by a drought of fifteen months, and were
accompanied and followed by torrents of rain which
swelled the rivers.

On the 14th December 1797, more than four-fifths of
the city were again entirely destroyed. Previous to
this, the shocks had been horizontal oscillations ; but
the shaking now felt was that of an elevation of the
ground, and was attended by a subterraneous noise, like
the explosion of a mine at a great depth. The most
violent concussion, however, was preceded by a slight
undulating motion, so that the inhabitants had time to
escape into the streets ; and only a few perished, who
had betaken themselves for safety to the churches.
Half an hour before the catastrophe, a strong smell of
sulphur was experienced near the hill of the convent of
St Francis ; and on the same spot an internal noise,
which seemed to pass from S.E. to N.W., was heard
loudest. Flames appeared on the banks of the I\Ian-
zanarcs and in the Gulf of Cariaco. In describing this
frightful convulsion of nature, our author enters upon
general views respecting earthquakes, of which a very
brief account may be here given.

The great earthquakes which interrupt the long series
of small shocks do not appear to have any stated times
at Cumana, as they have occurred at intervals of eighty,
of a hundred, and sometimes even of less than thirty
years ; whereas, on the coasts of Peru, — at Lima, for
example, — there is, without doubt, a certain degree of
regularity in the periodical devastations thereby occa-

It has long been believed at Cumana, Acapulco, and
Lima, that there exists a perceptible relation between
eartiiquakes and the state of the atmosphere which pre-
cedes these phenomena. On the coasts of New Anda-
lusia the people become uneasy when, in excessively
liot weather and after long drought, the breeze suddenly


ceases, and tlie sky, clear at the zenith, presents the chap. v.
appearance of a reddish vapour near the horizon. But
these prognostics are very uncertain, and the dreaded
evil has arrived in all kinds of weather.

Under the tropics the regularity of the horary vaT'ia- EfTect
tions of the haronieter is not disturhed on the days when n"ete'r ^^°'
violent shocks occur. In like manner, in the temperate
zone the aurora horealis does not always modify the
variations of the needle, or the intensity of the magnetic

When the earth is opened and agitated, gaseous Gaseous
emanations occasionally escape in places considerably emanatioas.
remote from unextinguished volcanoes. At Cumana,
flames and sulphureous vapours spring from the arid
soil, while in other parts of the same province it throws
out water and petroleum. At Riobamba, a muddy
inflammable mass called moya issues from crevices which Moya
close again, and forms elevated heaps. Flames and
smoke were also seen to proceed from the rocks of
Alvidras, near Lisbon, during the earthquake of 1755,
by which that city was ravaged. But in the greater
number of earthquakes it is probable that no elastic
fluids escape from the ground, and when gases are
evolved, they more frequently accompany or follow
than precede the shocks.

The subterranean noise which so frequently attends Sutten-a-
earthquakes is generally not proportionate to the strength "'^'*° """"^
of the shocks. At Cumana it always precedes them ;
while at Quito, and for some time past at Caraccas and
in the West India Islands, a noise like the discharge of
a battery was heard long after the agitation had ceased.
The rolling of thunder in the bowels of the earth, which
continues for months without being accompanied by the
least shaking, is a very remarkable phenomenon.

In all countries subject to earthquakes the point at
which the effects are greatest is considered as the source
or focus of the shocks. We forget that the rapidity
with which the undulations are propagated to great
distances, even across the basin of the ocean, proves the


in New


CHAP. V. centre of action to be very remote from the earth's
Diffusimi surface. Hence it is clear tliat earthquakes are not
of eartii- restricted to certain species of rocks, as some naturalists
**"" *"*■ assert, but pervade all ; although sometimes, in the

same rock, the upper strata seem to form an insuperable
obstacle to the propagation of the motion. It is curious
also, that in a district of small extent certain formations
interrupt the sliocks. Thus, at Cumana, before the
catastrophe of 1797, the earthquakes were felt only
along the southern or calcareous coast of the Gulf of
Cariaco, as far as the town of that name, while in the
peninsula of Araya, and at the village of Maniquarez,
the ground was not agitated. At present, however, the
peninsula is as liable to earthquakes ixs the district
around Cumana.
Eartiiquaki'4 In New Andalusia, as in Chili and Peru, the shocks
follow the line of the shore, and extend but little into
the interior, — a circumstance which indicates an inti-
mate connexion between the causes that produce earth-
quakes and volcanic eruptions. If the land along the
coasts is most agitated because it is generally lowest,
why should not the shocks be equally strong in the
savannahs, which are onl}' a few yards above the level
of the sea ?
Relation The earthquakes of Cumana are connected with those

Quakcv' <^f the West Indies, and are even suspected to have some
relation to the volcanic phenomena of tlie Andes. On
the 4th February 1797, the province of Quito under-
went so violent a conmiotion that 40,000 pursons were
destroyed ; and at the same period shocks were experi-
enced in the Eastern Antilles, followed by an ei-uption
of the volcano of Guadaloupe, in the end of September
1707. On the 14th December the great concussion
took place at Cumana.
r.^iont of It has long been remarked, that earthquakes extend

their cfl^ects to much greater distances than volcanoes ;
and it is i)roba))le, as has just been mentioned, that the
causes wliicli produce the former have an intimate con-
nexion with the latter. When seated within the verge



of a burning crater, one feels the motion of the ground cHAP. v.
several seconds before each partial eruption. The phe- . —
nomcna of earthquakes seem strongly to indicate the the giouud.
action of elastic fluids endeavouring to force their way
into the atmosphere. On the shores of the South Sea
the concussion is almost instantaneously communicated
from Chili to the Gulf of Guayaquil, over a space of
2070 miles. The shocks also appear to be so much the
stronger the more distant the country is from active
volcanoes ; and a province is more agitated, the smaller
the number of funnels by which the subterranean cavi-
ties communicate with the open air.




Residence at Cumana,

Lunar Halo — Africnn Slaves — Excursion to the Peninsula of Araya
— Geological Constitution of the Country — Salt-works of Arava
— Indians and Mulattoes — Pearl-fishery — Maniquarez — Mexi-
can Deer — Spring of Naphtha.

CHAP. Yl The occupations of our travellers were much disturLed
Disturbnnce during the first weeks of their abode at Cumana, by the
of TUitors. intrusion of persons desirous of examining their astro-
nomical and other instruments. They however deter-
mined the latitude of tlie great square to be 10° 27' 52",
and its longitude 64° 10' 2".
i.tmarhnio. ^^ *-'^^ ^'"''^^ ^^ August, a halo of the moon attracted
the attention of the inhabitants, who viewed it as the
presage of a violent earthquake. Coloured circles of
this kind, Humboldt remarks, are much rarer in the
northern than in the southern countries of Europe.
They are seen more especially when the sky is clear
and tlic weather settled. In the torrid zone they appear
ahnrist every night, and often in the space of a few
minutes disappear several times. Between the latitude
of 15° N. and tlic equator he has seen small haloes
around tlie planet Venus, but never observed any in
connexion witli the fixed stars. While the halo was
seen at Cumana, the liygrometer indicated great humi-
dity, altliough the atmosphere was perfectly transparent.
It consisted of two circles ; a larger, of a whitish colour,
and 44° in diameter, and a smaller, displaying all the



tints of the rainbow, and 1° 43' in diameter. The chap. \a
intermediate space was of the deepest azure. "

Part of the great square is surrounded with arcades, slave
over which is a long wooden gallery, where slaves '"aiiift
imported from the coast of Africa are sold. These were
young men from fifteen to twenty years of age. Every
morning cocoa-nut oil was given them, with which they
rubbed their skin, to render it glossy. The persons
who came to purchase them examined their teeth, as we
do those of horses, to judge of their age and health.
Yet the Spanish laws, according to our author, have
never favoured the trade in African slaves, the number
of whom in ] 800 did not exceed GOOO in the two pro-
vinces of Cumana and Barcelona, while the whole
population was estimated at 110,000.

The first excursion which our travellers made was to Excursion
the peninsula of Araya. They embarked on the Man- '** Araya.
zanares, near the Indian suburb, about two in the
morning of the 19th August. The night was delight-
fully cool. Swarms of shining insects (^Elater noctilucus)
sparkled in the air and along the banks of the river.
As the boat descended the stream they observed a com-
pany of negroes dancing to the music of the guitar by
the light of bonfires, — a practice which they prefer to
mere relaxation or sleep, on their daj's of rest.

The bark in which they passed the Gulf of Cariaco gj-eat cold,
was commodious, and large skins of the jaguar were
spread for their repose during the night. The cold,
however, prevented them from sleeping, although, as

Online LibraryAlexander von HumboldtThe travels and researches of Alexander von Humboldt → online text (page 5 of 35)