Alexander von Humboldt.

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to M. Peucliet, France feeds 6,000,000 of the large
horned class ; and in the Austrian monarcliy, the oxen,
cows, and calves, are estimated by Mr Lichtonstein at
about 13,400,000.

At Calabozo, in the midst of the Llanos, the travellers Hccfric
found an electrical apparatus nearly as complete as those appanitiis.
of Europe, made by a person who had rie\^er seen any
such instrument, had received no instructions, and was
acquainted with the phenomena of electricity only by
reading the treatise of Sigaud de la Fond, and Franklin's
Memoirs. Next to this piece of mechanism, the objects
that excited the greatest interest were the electrical eels, EiecMau
or gymnoti, which abound in the basins of stagnant ^«^
water and the confluents of the Orinoco. The dread of
the shocks given by these animals is so great among the
common people and Indians, that for some time no
specimens could be procured, and one which was at length
brought to them afforded very unsatisfactory results.

On the 19th March, at an early hour, they set off" for catching
the village of Rastro de Abaxo, whence they were con- gymnoti.
ducted by the natives to a stream, which in the dry
season forms a pool of muddy water surrounded by
trees. It being very difficult to catch the gymnoti with
nets, on account of their extreme agility, it was resolved
to procure some by intoxicating or benumbing them
with the roots of certain plants, which when thrown into
the water produce that effect. At this juncture the
Indians informed them that they would fish with horses,
and soon brought from the savannah about thirty of
these animals, which they drove into the pool.

" The extraordinary noise caused by the horses' hoofs Fisiung with
makes the fishes issue from the mud, and excites them horses.
to combat. These yellowish and livid eels resembling
large aquatic snakes, swim at the surface of the water,
and crowd under the bellies of the horses and mules.


CHAP. XV. The struggle 1)et\vecn animals of so different an organiza-
— tion affords a very interesting sight. The Indians,
nl!he"^ furnisliod with harpoons and long slender reeds, closely

surround tlie pool. Some of tliem climb the trees,
whose branches stretch horizontally over the water. By
their wild cries and their long reeds, they prevent the
horses from coming to the edge of the basm. The eels,
stunned by the noise, defend themselves by repeated
discharges of their electrical batteries, and for a long
time seem likely to obtain the victory. Several horses
T> str ctinn ^'"^ under the violence of the invisible blows which
01 tiie iiorsia they receive in the organs most essential to life, and,
benumbed by the force and frequency of the shocks,
disiippear beneath the surface. Others, panting, with
erect mane, and haggard eyes expressive of anguish,
raise themselves and endeavour to escape from the storm
which overtakes them, but are driven back by the
Indians. A few, however, succeed in eluding the active
vigilance of the fishers ; they gain the shore, stumble at
every step, and stretch themselves out on the sand, ex-
hausted with fatigue, and having their limbs benumbed
by the electric shocks of the gymnoti.
Kiectric "-^^ ^'-'^^ than five minutes two horses were killed,

discharge of The eel, which is five feet long, presses itself against the
' ^ *' belly of the horse, and makes a discharge along the whole

extent of its electric organ. It attacks at once the heart,
the viscera, and the ca;liac plexus of the abdominal
nerves. It is natural that the effect which a horse ex-
periences should be more powerful tlian that produced
by the same fish on man, when he touches it only by
one of the extremities. The horses are probably not
killed but only stunned ; they are drowned from the
impossibility of rising amid the prolonged struggle
between the other horses and eels."
Capture of '^^^^ gymnoti at length dispersed, and approached the
the g)iimoil. edge of the pool, when five of them were taken by means
of small hari)oons fastened to long cords. A few more
were caught towards evening, and there was thus ob-
tained a sufficient number of specimens on which to


make experiments. Tlie results of Humboldt's obscrva- chap. xv.

tions on these animals may be stated briefly as follows : — ,, "^ ,
mi -11 1 ■ -1 . Expennients

liie gymnotus is the largest electrical fish known, on the

some of those measured by him being from 5 feet 4 ^'i™^*"'"^

inches to 6 feet 7 inches in length. One, 4 feet 1 inch

long, weighed 16| Troy pounds, and its transverse

diameter was 3 inches 7^ lines. The colour Avas a

fine olive-green ; tlie under part of the head yellow

mingled with red. Along the back are two rows of

small yellow spots, each of which contains an excretory

aperture for the mucus, with which the skin is constantly

covered. The swimming-bladder is of large size, and

before it is situated another of smaller dimensions ; the

former separated from the skin by a mass of fat, and

resting upon the electric organs, which occupy more

than two-thirds of the fish.

It would be rash to expose one's self to the first Danger from
shocks of a very large individual, — the pain and numb- *^^ shock,
ness which follow in such a case being extremely
violent. When in a state of great weakness, the animal
produces in the person who touches it a twitching,
which is propagated from the hand to the elbow ; a
kind of internal vibration lasting two or three seconds,
and followed by painful torpidity, being felt after every
stroke. The electric energy depends upon the will of
the creature, and it directs it toward the point where it
feels most strongly irritated. The organ acts only Organ of
under the hnmediate influence of the brain and heart ; ^'^^''^"^
for, when one of them was cut through the middle, the
fore part of the body alone gave shocks. Its action on
man is transmitted and intercepted by the same sub-
stances that transmit and intercept the electrical current
of a conductor charged by a Leyden jar or a Voltaic
pile. In the water the shock can be conveyed to a con-
siderable distance. No spark has ever been observed to
issue from the body of the eel when excited.

The gymnoti are objects of dread to the natives, and
their presence is considered as the principal cause of the


want of fisli in tlie pools of the Llanos. All the inha-
bitants of the waters avoid them ; and the Indians
asserted, that when they take young alligators and these
animals in tlie same net, tiie latter never display any
appearance of wounds, because they disable their ene-
mies before they are attacked Jiy them. It became
nece^sary to change tiie direction of a road near Urituco,
solely because they were so numerous in a river that
they killed many mules in the course of fording it.

On the 2J:th March the travellers left Calabozo, and
advanced southward. As they proceeded they found
the country more dusty and destitute of herbage. The
palm-trees gradually disappeared. From eleven in the
morning till sunset the thermometer kept at 03° or 95-'.
Although the air was calm at the height of eight or ten
feet, the ground was swept by little currents which
raised clouds of dust. About four in the afternoon
they observed in the savannah a young Indian girl,
twelve or thirteen years of age, quite naked, lying on
her back, exhausted with fatigue and thirst, and with
her eyes, nostrils, and mouth, filled with dust. Her
breathing was stertorous, and she was unable to answer
the questions put to her. Happily one of the mules
was laden with water, the application of which to her
face aroused her. She was at first frightened, but by
degrees took courage, and conversed with the guides.
As she could not be prevailed upon to mount the beasts
of liurden, nor to return to Urituco, she Avas furnished
with some water ; upon which she resumed her way,
and was soon separated from her preservers by a cloud
of dust.

In the night they forded the Rio Urituco, which is
filled with crocodiles remarkable for their ferocit\',
although those of the Rio Tisnao in the neighbourhood
are not at all dangerous. They were shown a hut or
shed, in wliich a singular scene had been witnessed by
their host of Calabozo, who, having slept in it upon a
bench covered with leather was awakened carlv in the


morning by a violent shaking, accompanied with a chap. xv.
liorrible noise. Presently an alligator two or three ^- T~
feet long issued from under the l)ed, and darted at a dog iucideut
lying on the threshold, but missing him ran toward the
river. When the spot where the bench stood was
examined, the dried mud was found turned up to a con-
siderable depth, Avhere the alligator had lain in its state
of torpidity or summer sleep. The hut being situated
on the edge of a pool, and inundated during part of the
year, the animal had no doubt entered at that period
and concealed itself in the mire. The Indians often
find enormous boas, or water-serpents, in the same
lethargic state.

On the 25th March they passed over the smoothest The Mesa de
part of the steppes of Caraccas, the Mesa dc Pavones. '■'^™''<^s.
As far as the eye could reach, no object fifteen inches
high could be discovered excepting cattle, of which they
met some large herds accompanied by flocks of the
crotophaga ani, a bird of a black colour with olive
reflections. They were exceedingly tame, and perched
upon the quadrupeds in search of insects.

Wherever excavations had been made, they found the ^ogts.
rock to be old red sandstone or conglomerate, in which
were observed fragments of quartz, kieselschiefer, and
lydian stone. The cementing clay is feiTuginous, and
often of a very bright red. This formation, which
covers an extent of several thousand square leagues,
rests on the northern margin of the plains upon transi-
tion-slate, and to the south upon the granites of the

After wandering a long time on the desert and path- farm-houso
less savannahs of the IMesa de Pavones, they were agree- and -siUage.
ably surprised to find a solitary farm-house surrounded
with gardens and pools of clear water. Farther on they
passed the night near the village of San Geronymo del
Guyaval, situated on the banks of the Rio Guarico,
which joins the Apure. The ecclesiastic, who was a
young man, and had no other habitation than his


Arrival at
San Ker


cl lurch, received them in the kindest manner. Crossing
tile Guarico they encamped in the plain, and early in
tiie morning pursued their way over low grounds wliich
are often inundated. On the 27th they arrived at the
Villa de San Fernando, and terminated their journey
over the Llanos.



Voyage down the Rio Apure.

San Fernando — Commencement of the Rainy Season — Progress of
Atmospherical Phenomena — Cetaceous Animals — Vo3-a<^e down
the Rio Apure — Vegetation and Wild Animals — Crocodiles,
Chiguires, and Jaguars — Don Ignacio and Donna Isabella — Wa-
ter-fowl — Nocturnal Howlings in the Forest — Caribe-fish — Ad-
venture with a Jaguar — Manatees — Mouth of the Rio Apure.

The town of San Fernando, which was founded only in chap. XVX
1789, is advantageously situated on a large navigable xowiToTsan
river, the Apure, a tributary of the Orinoco, near the Fernando.
mouth of another stream which traverses the whole
province of Varinas, all the productions of which pass
through it on their way to the coast. It is during the
rainy season, when the rivers overflow their banks and
inundate a vast extent of country, that commerce is
most active. At this period the savannahs are covered
with water to the depth of twelve or fourteen feet, and j;:iiiiy
present the appearance of a great lake, in the midst of '*'^*'^""'
which the farm-houses and villages are seen rising on
islands scarcely elevated above the surface. Horses,
mules, and cows, perish in great numbers, and afford
abundant food to the zamuros or carrion-vultures, as
well as to the alligators. The inhabitants, to avoid the
force of the currents, and the danger arising from the
trees carried down by them, instead of ascending the
course of the rivers, find it safer to cross the fiats in
their boats.


ciiAr. XVI. San Fernando is celebrated for the excessive heat
— wliich prevails there during the greater part of the year.

^.xctssi\ ,^,j^^ travellers found the white sand of the shores,
wherever it was exposed to the sun, to have a tempera-
ture of 120*5°, at two in the afternoon. The thermo-
meter, raised eighteen inclies above the sand, indicated
109' ; and at six feet, 101-7°. The temperature of the
air in the shade was 97°. These observations were
made during a dead calm, and when the wind began to
blow the heat increased five degrees.

Tliunder. 0" the 28th .March, Humboldt and his companion

being on the shore at sunrise, heard the thunder rolling
all around, although as yet there were only scattered
clouds, advancing in opposite directions toward the
zenitli. Deluc's hygrometer was at SS'', the thermo-
meter stood at 7-4-7°, and the electrometer gave no par-
ticular indication. As the clouds mustered, the blue of
the sky changLd to deep azure, and then to gray ; and
when it was completely overcast the thermometer rose

Meteorologi- several degrees. Although a heavy rain fell, the tra-

tnena.'^"'*' vellers remained on tlie shore to observe the electrometer.
When it was held at the height of six feet from the
ground, the pith-balls genei-ally separated only a few
seconds before the lightning was seen. The separation
was four lines. The electric charge remained the same
for several minutes, and there were repeated oscillations
from positive to negative. Toward the end of the storm
the west wind blew with great impetuosity, and when
the clouds dispersed the thermometer fell to 71*6°.

oi.iect of Humboldt states, that he enters into these details

'''"^'''^^"'""' because Europeans usually confine themselves to a
description of the impressions made on their minds by
the solemn spectacle of a tropical thunder-storm ; and
because, m a country wliere tlie year is divided into two
great seasons of drought and rain, it is interesting to
trace the transition from the one to the other. In the
valleys of Aragua, he had from the 18th of February
observed clouds forming in the evening, and in the
beginning of March the accumulation of vesicular va-


pcurs became visible. Flashes of lightning were seen chap. xvi.
in the south, and at sunset Volta's electrometer rcgu- ^ hT^ ,
larly displayed positive indications, the separation of tlie
pith-balls being from three to four lines. After the
26th of the latter month the electrical equilibrium of
the atmosphere seemed broken, although the hygrometer
still denoted great dryness.

The following is an account of the atmospheric phe- Atmospheric
nomena in the inland districts to the east of the cordil- Plitnouiena.
leras of Merida and New Grenada, in the Llanos of
Venezuela, and the Rio Meta, from the fourth to the
tenth degree of north latitude, wherever the rains
continue from May to October, and consequently include
the period of the greatest heat, which is in July and
A-Ugust : — " Nothing can equal the purity of the atmo-
sphere from December to February. The sky is then
constantly without clouds, and should one appear, it ia
a phenomenon that occupies all the attention of the
inhabitants. The breeze from the east and north-east
blows with violence. As it always carries with it air of
the same temperature, the vapours cannot become visible
througli refrigeration. Towards the end of February
and the beginning of March, the blue of the sky is less Hamidity,
intense ; the hygrometer gradually indicates greater
humidity ; the stars are sometimes veiled by a thin
stratum of vapours ; their light ceases to be tranquil
and planetary ; and they are seen to sparkle from time
to time at the height of 20° above the horizon. At this
period the breeze diminishes in strength, and becomes
less regular, being more frequently interrupted by dead
calms. Clouds accumulate towards the south-east, ap- Clouds.
pearing like distant mountains with distinct outlines, •
From time to time they are seen to separate from the
horizon, and traverse the celestial vault with a rapidity
which has no correspondence with the feebleness of the
■wind that prevails in the lower strata of the air. At
the end oi March the southern region of the atmosphere
is illuminated by small electric explosions, like phos-
phorescent gleams confined to a single group of vanours.


ciiAr. XVL From this period the breeze shifts at intervals, and for
several hours, to the west and south-west, affording a
sure indication of the approach of the rainy season,
which on tlie Orinoco commences about the end of
April. The sky begins to be overcast, its azure colour
Ileat iisappears, and a gray tint is uniformly diffused over it.

At the same time the heat of the atmosphere gradually
increases, and instead of scattered clouds the whole
vault of the heavens is overspread with condensed
vapours. The howling-monkeys begin to utter their
plaintive cries long before sunrise. The atmospheric
Atmospheric electricity, which, during the period of the greatest
L-iecnidtj-. drought, from December to March, had been almost
constantly in the daytime from 1-7 to 2 lines to Volta's
electrometer, becomes extremely variable after March.
During whole days it appears null, and again, for some
hours, the pith-ljalls of the electrometer diverge from
three to four lines. The atmosphere, which in the
tori'id as in the temperate zone is generally in a state of
positive electricity, passes alternately, in tlie course of
eight or ten minutes, to the negative state. The rainy
season is that of tlmnder-storms ; and yet I have found,
from numerous experiments made during three years,
that at this season the electric tension is less in the
lower regions of the atmosphere. Are thunder-storms
the effect of this unequal charge of the different super-
imposed strata of the air ? What prevents the electri-
city from descending towards the earth in a stratum of
air which has become more humid since the month of
Accumuia- March \ At this period the electricity, in place of being
c/ccirkity ^^'^^scd through the whole atmosphere, would seem to
be accumulated on the outer envelope at the surface of
the clouds. According to M. Gay Lussac, it is the for-
mation of the cloud itself that carries the fluid toward
the surface. The storm rises in the phiins two hours
after tlie sun passes through the meridian, and therefore
shortly after the period of the maxinmm of the diurnal
heat in the tropics. In the inland districts it is exceed-
ingly rare to luar thunder at nii^lit or in the mornimr.


nocturnal thunder-storms being peculiar to certain val- chap, xvi

leys of rivers which have a particular climate."

It may be interesting to present a very brief state- Explanation
ment of Humboldt's explanation of these phenomena : °\^^'^
— The season of rains and thunder in the northern
equinoctial zone coincides with the passage of the sun
through the zenith of the place, the cessation of the
breezes or north-east winds, and the frequency of calms,
and furious currents of the atmosphere from the south-
east and south-west, accompanied with a cloudy sky.
While the breeze from tlie north-east blows, it prevents
the atmosphere from being saturated with moisture.
Tlie hot and loaded air of the torrid zone rises and flows
off again towards the poles, while inferior currents from
these last, bringing drier and colder strata, take the
place of the ascending columns. In tliis manner the
humidity, being prevented from accumulating, passes
off towards the temperate and colder regions, so that the
sky is always clear. When the sun, entering the
northern signs, rises towards the zenith, the breeze
from the north-east softens, and at length ceases ; this
being the season at which the difference of temperature
between the troj)ics and tlie contiguous zone is least.

The column of air resting on the equinoctial zone ,r ,

° , . . , Vapour ana

becomes replete with vapours, because it is no longer clouds.

renewed by the current from the pole ; clouds form in

this atmosphere, saturated and cooled by the effects oi

radiation and the dilatation of the ascending air, which

increases its capacity for heat in proportion as it is rari-

lied. Electricity accumulates in the higher regions in

consequence of the formation of the vesicular vapours,

the precipitation of which is constant during the day,

but generally ceases at night. The showers are more

violent, and accompanied with electrical explosions,

shortly after the maximum of the diurnal heat. These

phenomena continue until the sun enters the southern

signs, when the polar current is re-established, because

the difference between the heat of the equiuoctial and

temperate regions is daily increasing. The air of the


CHAP. XVL tropics being thus renewed, the rains cease, the vapour?
are dibsolved, and the sky resumes its azure tint.

Cctacious At San Fernando, IlumLoldt observed in the river

■"^^^^"^ long files of cetaceous animals resembling the common
porpoise. The crocodiles seemed to dislike them, and
dived whenever thoy approached. They ■were three or
four feet long, and appear to be peculiar to the great
streams of South America, as he saw some of them above
the cataracts of the Orinoco, whither they could not
have ascended from the sea.

Rainv season. The rainy season had now commenced, and as the
way to that river by land lies across an unhealthy and
uninteresting flat, they preferred the longer way by the
Rio Apure, and embarked in a large canoe or lancha,
having a pilot and four Indians for crew. A cabin was
constructed in the stern, of sufficient size to hold a table
and benches, and covered with corypha-leaves. They

Provisions put on board a stock of provisions for a month, while

iuiavoyuse. ^j^g Capuchin missionary, with whom they had lodged
during their stay, supplied them with wine, oranges, and
tamarinds. Fishing-instniments, fire-arms, and some
casks of brandy, for bartering with the natives, were
added to their store. On the 30th March, at four in the
afternoon, they left San Fernando, accompanied by Don
Nicolas Sojio, brother-in-law of the governor of the
province. The river abounds in fish, manatees, and
turtles, and its banks are peopled by numberless birds,
of which the pauxi and guacharaca are the most useful

Apurita ^^ man. Passing the mouth of the A purito, they coasted
the island of the same name, formed by the Apure and
Guarico, and which is seventy-six miles in length. On
the banks they saw huts of the Yaruroes, who live by
liunting and fishing, and are very skilful in killing
jaguars, tlic skins of which they dispose of in the
Spanish villages. Tlie iiight was passed at Diamante, a
small sugar-plantation.

On the .31st a contrary wind obliged them to remain
on shore till noon, when they embarked, and as they
proceeded found the river gradually widcnmg ; one of


its banks being generally sandy and barren, the other CIIAP. xvi.
liigher and covered with tail trees. Sometimes, how- nankTofthe
ever, it was bordered on both sides l)y forests, and re- 1''" Ai>iir&
sembled a straiglit canal 320 yards in breadth. Bushes of
sauso (Permesia castancifolia) formed along the margins
a kind of hedge about four feet high, in which the
jaguars, tapirs, and pecaris, had made openings for the
purpose of drinking ; and as these animals manifest
little fear at the approach of a boat, the travellers had
the pleasure of viewing them as they walked slowly
along the shore, until they disappeared in tlie forest.
When the sauso-hedge was at a distance from the
current, crocodiles were often seen in parties of eight or CrocodOos.
ten, stretched out on the sand motionless, and with their
jaws opened at right angles. These monstrous reptiles
were so numerous, that throughout the whole course oi
the river there were usually five or six in view, although
the waters had scarcely begun to rise, and hundreds
were still buried in the mud of the savannahs. A dead
individual which they found was 17 feet 9 inches long,

Online LibraryAlexander von HumboldtThe travels and researches of Alexander von Humboldt → online text (page 14 of 35)