Books: Equinoctial Regions of America V3
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Alexander von Humboldt >> Equinoctial Regions of America V3
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The secondary formations on the east of the Havannah are pierced in a
singular manner by syenitic and euphotide rocks united in groups. The
southern bottom of the bay as well as the northern part (the hills of
the Morro and the Cabana) are of Jura limestone; but on the eastern
bank of the two Ensenadas de Regla and Guanabacoa, the whole is
transition soil. Going from north to south, and first near Marimelena,
we find syenite consisting of a great quantity of hornblende, partly
decomposed, a little quartz, and a reddish-white feldspar seldom
crystallized. This fine syenite, the strata of which incline to the
north-west, alternates twice with serpentine. The layers of
intercalated serpentine are three toises thick. Farther south, towards
Regla and Guanabacoa, the syenite disappears, and the whole soil is
covered with serpentine, rising in hills from thirty to forty toises
high, and running from east to west. This rock is much fendillated,
externally of a bluish-grey, covered with dendrites of manganese, and
internally of leek and asparagus-green, crossed by small veins of
asbestos. It contains no garnet or amphibole, but metalloid diallage
disseminated in the mass. The serpentine is sometimes of an
esquillous, sometimes of a conchoidal fracture: this was the first
time I had found metalloid diallage within the tropics. Several blocks
of serpentine have magnetic poles; others are of such a homogeneous
texture, and have such a glossiness, that at a distance they may be
taken for pechstein (resinite). It were to be wished that these fine
masses were employed in the arts as they are in several parts of
Germany. In approaching Guanabacoa we find serpentine crossed by veins
between twelve and fourteen inches thick, and filled with fibrous
quartz, amethyst, and fine mammelonnes, and stalactiforme
chalcedonies; it is possible that chrysoprase may also one day be
found. Some copper pyrites appear among these veins accompanied, it is
said, by silvery-grey copper. I found no traces of this grey copper:
it is probably the metalloid diallage that has given the Cerro de
Guanabacoa the reputation of riches in gold and silver which it has
enjoyed for ages. In some places petroleum flows* from rents in the
serpentine. (* Does there exist in the Bay of the Havannah any other
source of petroleum than that of Guanabacoa, or must it be admitted
that the betun liquido, which in 1508 was employed by Sebastian de
Ocampo for the caulking of ships, is dried up? That spring, however,
fixed the attention of Ocampo on the port of the Havannah, where he
gave it the name of Puerto de Carenas. It is said that abundant
springs of petroleum are also found in the eastern part of the island
(Manantialis de betun y chapapote) between Holguin and Mayari, and on
the coast of Santiago de Cuba.) Springs of water are frequent; they
contain a little sulphuretted hydrogen, and deposit oxide of iron. The
Baths of Bareto are agreeable, but of nearly the same temperature as
the atmosphere. The geologic constitution of this group of serpentine
rocks, from its insulated position, its veins, its connection with
syenite and the fact of its rising up across shell-formations, merits
particular attention. Feldspar with a basis of souda (compact
feldspar) forms, with diallage, the euphotide and serpentine; with
pyroxene, dolerite and basalt; and with garnet, eclogyte. These five
rocks, dispersed over the whole globe, charged with oxidulated and
titanious iron, are probably of similar origin. It is easy to
distinguish two formations in the euphotide; one is destitute of
amphibole, even when it alternates with amphibolic rocks (Joria in
Piedmont, Regla in the island of Cuba) rich in pure serpentine, in
metalloid diallage and sometimes in jasper (Tuscany, Saxony); the
other, strongly charged with amphibole, often passing to diorite,* has
no jasper in layers, and sometimes contains rich veins of copper;
(Silesia, Mussinet in Piedmont, the Pyrenees, Parapara in Venezuela,
Copper Mountains of North America). (* On a serpentine that flows like
a penombre, veins of greenstone (diorite) near Lake Clunie in
Perthshire. See MacCulloch in Edinburgh Journal of Science 1824 July
pages 3 to 16. On a vein of serpentine, and the alterations it
produces on the banks of Carity, near West-Balloch in Forfarshire see
Charles Lyell l.c. volume 3 page 43.) It is the latter formation of
euphotide which, by its mixture with diorite, is itself linked with
hyperthenite, in which real beds of serpentine are sometimes developed
in Scotland and in Norway. No volcanic rocks of a more recent period
have hitherto been discovered in the island of Cuba; for instance,
neither trachytes, dolerites, nor basalts. I know not whether they are
found in the rest of the Great Antilles, of which the geologic
constitution differs essentially from that of the series of calcareous
and volcanic islands which stretch from Trinidad to the Virgin
Islands. Earthquakes, which are in general less fatal at Cuba than at
Porto Rico and Hayti, are most felt in the eastern part, between Cape
Maysi, Santiago de Cuba and La Ciudad de Puerto Principe. Perhaps
towards those regions the action of the crevice extends laterally,
which is believed to cross the neck of granitic land between
Port-au-Prince and Cape Tiburon and on which whole mountains were
overthrown in 1770.
The cavernous texture of the limestone formations (soboruco) just
described, the great inclination of the shelvings, the smallness of
the island, the nakedness of the plains and the proximity of the
mountains that form a lofty chain on the southern coast, may be
considered as among the principal causes of the want of rivers and the
drought which is felt, especially in the western part of Cuba. In this
respect, Hayti, Jamaica, and several of the Lesser Antilles, which
contain volcanic heights covered with forests, are more favoured by
nature. The lands most celebrated for their fertility are the
districts of Xagua, Trinidad, Matanzas and Mariel. The valley of
Guines owes its reputation to artificial irrigation (sanjas de riego).
Notwithstanding the want of great rivers and the unequal fertility of
the soil, the island of Cuba, by its undulated surface, its
continually renewed verdure, and the distribution of its vegetable
forms, presents at every step the most varied and beautiful landscape.
Two trees with large, tough, and glossy leaves, the Mammea and the
Calophyllum calaba, five species of palm-trees (the palma real, or
Oreodoxa regia, the common cocoa-tree, the Cocos crispa, the Corypha
miraguama and the C. maritima), and small shrubs constantly loaded
with flowers, decorate the hills and the savannahs. The Cecropia
peltata marks the humid spots. It would seem as if the whole island
had been originally a forest of palm, lemon, and wild orange trees.
The latter, which bear a small fruit, are probably anterior to the
arrival of Europeans,* who transported thither the agrumi of the
gardens; they rarely exceed the height of from ten to fifteen feet. (*
The best informed inhabitants of the island assert that the cultivated
orange-trees brought from Asia preserve the size and all the
properties of their fruits when they become wild. The Brazilians
affirm that the small bitter orange which bears the name of loranja do
terra and is found wild, far from the habitations of man, is of
American origin. Caldcleugh, Travels in South America.) The lemon and
orange trees are most frequently separate; and the new planters, in
clearing the ground by fire, distinguish the quality of the soil
according as it is covered with one or other of those groups of social
plants; they prefer the soil of the naranjal to that which produces
the small lemon. In a country where the making of sugar is not
sufficiently improved to admit of the employment of any other fuel
than the bagasse (dried sugar-cane) the progressive destruction of the
small woods is a positive calamity. The aridity of the soil augments
in proportion as it is stripped of the trees that sheltered it from
the heat of the sun; for the leaves, emitting heat under a sky always
serene, occasion, as the air cools, a precipitation of aqueous
vapours.
Among the few rivers worthy of attention, the Rio Guines may be
noticed, the Rio Armendaris or Chorrera, of which the waters are led
to the Havannah by the Sanja de Antoneli; the Rio Canto on the north
of the town of Bayamo; the Rio Maximo which rises on the east of
Puerto Principe; the Rio Sagua Grande near Villa Clara; the Rio de las
Palmas which issues opposite Cayo Galiado; the small rivers of Jaruco
and Santa Cruz between Guanabo and Matanzas, navigable at the distance
of some miles from their mouths and favourable for the shipment of
sugar-casks; the Rio San Antonio which, like many others, is engulfed
in the caverns of limestone rocks; the Rio Guaurabo west of the port
of Trinidad; and the Rio Galafre in the fertile district of Filipinas,
which throws itself into the Laguna de Cortez. The most abundant
springs rise on the southern coast where, from Xagua to Punta de
Sabina, over a length of forty-six leagues, the soil is extremely
marshy. So great is the abundance of the waters which filter by the
clefts of the stratified rock that, from the effect of an hydrostatic
pressure, fresh water springs far from the coast, and amidst salt
water. The jurisdiction of the Havannah is not the most fertile part
of the island; and the few sugar-plantations that existed in the
vicinity of the capital are now converted into farms for cattle
(potreros) and fields of maize and forage, of which the profits are
considerable. The agriculturists of the island of Cuba distinguish two
kinds of earth, often mixed together like the squares of a
draught-board, black earth (negra o prieta), clayey and full of
moisture, and red earth (bermeja), more silicious and containing oxide
of iron. The tierra negra is generally preferred (on account of its
best preserving humidity) for the cultivation of the sugarcane, and
the tierra bermeja for coffee; but many sugar plantations are
established on the red soil.
The climate of the Havannah is in accordance with the extreme limits
of the torrid zone: it is a tropical climate, in which a more unequal
distribution of heat at different parts of the year denotes the
passage to the climates of the temperate zone. Calcutta (latitude 22
degrees 34 minutes north), Canton (latitude 23 degrees 8 minutes
north), Macao (latitude 22 degrees 12 minutes north), the Havannah
(latitude 23 degrees 9 minutes north) and Rio Janeiro (latitude 22
degrees 54 minutes south) are places which, from their position at the
level of the ocean near the tropics of Cancer and Capricorn,
consequently at an equal distance from the equator, afford great
facilities for the study of meteorology. This study can only advance
by the determination of certain numerical elements which are the
indispensable basis of the laws we seek to discover. The aspect of
vegetation being identical near the limits of the torrid zone and at
the equator, we are accustomed to confound vaguely the climates of two
zones comprised between 0 and 10 degrees, and between 15 and 23
degrees of latitude. The region of palm-trees, bananas and arborescent
gramina extends far beyond the two tropics: but it would be dangerous
to apply what has been observed at the extremity of the tropical zone
to what may take place in the plains near the equator. In order to
rectify those errors it is important that the mean temperature of the
year and months be well known, as also the thermometric oscillations
in different seasons at the parallel of the Havannah; and to prove by
an exact comparison with other points alike distant from the equator,
for instance, with Rio Janeiro and Macao, that the lowering of
temperature observed in the island of Cuba is owing to the irruption
and the stream of layers of cold air, borne from the temperate zones
towards the tropics of Cancer and Capricorn. The mean temperature of
the Havannah, according to four years of good observations, is 25.7
degrees (20.6 degrees R.), only 2 degrees centigrade above that of the
regions of America nearest the equator. The proximity of the sea
raises the mean temperature of the year on the coast; but in the
interior of the island, when the north winds penetrate with the same
force, and where the soil rises to the height of forty toises, the
mean temperature attains only 23 degrees (18.4 degrees R.) and does
not exceed that of Cairo and Lower Egypt. The difference between the
mean temperature of the hottest and coldest months rises to 12 degrees
in the interior of the island; at the Havannah and on the coast, to 8
degrees; at Cumana, to scarcely 3 degrees. The hottest months, July
and August, attain 28.8 degrees, at the island of Cuba, perhaps 29.5
degrees of mean temperature, as at the equator. The coldest months are
December and January; their mean temperature in the interior of the
island, is 17 degrees; at the Havannah, 21 degrees, that is, 5 to 8
degrees below the same months at the equator, yet still 3 degrees
above the hottest month at Paris.
It will be interesting to compare the climate of the Havannah with
that of Macao and Rio Janeiro; two places, one of which is near the
limit of the northern torrid zone, on the eastern coast of Asia; and
the other on the eastern coast of America, towards the extremity of
the southern torrid zone.
The climate of the Havannah, notwithstanding the frequency of the
north and north-west winds, is hotter than that of Macao and Rio
Janeiro. The former partakes of the cold which, owing to the frequency
of the west winds, is felt in winter along all the eastern coast of a
great continent. The proximity of spaces of land covered with
mountains and table-lands renders the distribution of heat in
different months of the year more unequal at Macao and Canton than in
an island bounded on the west and north by the hot waters of the
Gulf-stream. The winters are therefore much colder at Canton and Macao
than at the Havannah: yet the latitude of Macao is 1 degree more
southerly than that of the Havannah; and the latter town and Canton
are, within nearly a minute, on the same parallel. The thermometer at
Canton has sometimes almost reached the point zero; and by the effect
of reflection, ice has been found on the terraces of houses. Although
this great cold never lasts more than one day, the English merchants
residing at Canton like to make chimney-fires in their apartments from
November to January; while at the Havannah, the artificial warmth even
of a brazero is not required. Hail is frequent and the hail-stones are
extremely large in the Asiatic climate of Canton and Macao, while it
is scarcely seen once in fifteen years at the Havannah. In these three
places the thermometer sometimes keeps up for several hours between 0
and 4 degrees (centigrade); and yet (a circumstance which appears to
be very remarkable) snow has never been seen to fall; and
notwithstanding the great lowering of the temperature, the bananas and
the palm-trees are as beautiful around Canton, Macao and the Havannah
as in the plains nearest the equator.
In the island of Cuba the lowering of the temperature lasts only
during intervals of such short duration that in general neither the
banana, the sugar-cane nor other productions of the torrid zone suffer
much. We know how well plants of vigorous organization resist
temporary cold, and that the orange trees of Genoa survive the fall of
snow and endure cold which does not more than exceed 6 or 7 degrees
below freezing-point. As the vegetation of the island of Cuba bears
the character of the vegetation of the regions near the equator, we
are surprised to find even in the plains a vegetable form of the
temperate climates and mountains of the equatorial part of Mexico. I
have often directed the attention of botanists to this extraordinary
phenomenon in the geography of plants. The pine (Pinus occidentalis)
is not found in the Lesser Antilles; not even in Jamaica (between 17
3/4 and 18 1/2 degrees of latitude). It is only seen further north, in
the mountains of San Domingo, and in all that part of the island of
Cuba situated between 20 and 23 degrees of latitude. It attains a
height of from sixty to seventy feet; and it is remarkable that the
cahoba* (mahogany (* Swieteinia Mahogani, Linn.)) and the pine
vegetate at the island of Pinos in the same plains. We also find pines
in the south-eastern part of the island of Cuba, on the declivity of
the Copper Mountains where the soil is barren and sandy. The interior
table-land of Mexico is covered with the same species of coniferous
plants; at least the specimens brought by M. Bonpland and myself from
Acaguisotla, Nevado de Toluca and Cofre de Perote do not appear to
differ specifically from the Pinus occidentalis of the West India
Islands described by Schwartz. Now those pines which we see at sea
level in the island of Cuba, in 20 and 22 degrees of latitude, and
which belong only to the southern part of that island, do not descend
on the Mexican continent between the parallels of 17 1/2 and 19 1/2
degrees, below the elevation of 500 toises. I even observed that, on
the road from Perote to Xalapa in the eastern mountains opposite to
the island of Cuba, the limit of the pines is 935 toises; while in the
western mountains, between Chilpanzingo and Acapulco, near
Quasiniquilapa, two degrees further south, it is 580 toises and
perhaps on some points 450. These anomalies of stations are very rare
in the torrid zone and are probably less connected with the
temperature than with the nature of the soil. In the system of the
migration of plants we must suppose that the Pinus occidentalis of
Cuba came from Yucatan before the opening of the channel between Cape
Catoche and Cape San Antonio, and not from the United States, so rich
in coniferous plants; for in Florida the species of which we have here
traced the botanical geography has not been discovered.
About the end of April, M. Bonpland and myself, having completed the
observations we proposed to make at the northern extremity of the
torrid zone, were on the point of proceeding to Vera Cruz with the
squadron of Admiral Ariztizabal; but being misled by false
intelligence respecting the expedition of Captain Baudin, we were
induced to relinquish the project of passing through Mexico on our way
to the Philippine Islands. The public journals announced that two
French sloops, the Geographe and Naturaliste, had sailed for Cape
Horn; that they were to proceed along the coasts of Chili and Peru,
and thence to New Holland. This intelligence revived in my mind all
the projects I had formed during my stay in Paris, when I solicited
the Directory to hasten the departure of Captain Baudin. On leaving
Spain, I had promised to rejoin the expedition wherever I could reach
it. M. Bonpland and I resolved instantly to divide our herbals into
three portions, to avoid exposing to the risks of a long voyage the
objects we had obtained with so much difficulty on the banks of the
Orinoco, the Atabapo and the Rio Negro. We sent one collection by way
of England to Germany, another by way of Cadiz to France, and a third
remained at the Havannah. We had reason to congratulate ourselves on
this foresight: each collection contained nearly the same species, and
no precautions were neglected to have the cases, if taken by English
or French vessels, remitted to Sir Joseph Banks or to the professors
of natural history at the Museum at Paris. It happened fortunately
that the manuscripts which I at first intended to send with the
collection to Cadiz were not intrusted to our much esteemed friend and
fellow traveller, Fray Juan Gonzales, of the order of the Observance
of St. Francis, who had followed us to the Havannah with the view of
returning to Spain. He left the island of Cuba soon after us, but the
vessel in which he sailed foundered on the coast of Africa, and the
cargo and crew were all lost. By this event we lost some of the
duplicates of our herbals, and what was more important, all the
insects which M. Bonpland had with great difficulty collected during
our voyage to the Orinoco and the Rio Negro. By a singular fatality,
we remained two years in the Spanish colonies without receiving a
single letter from Europe; and those which arrived in the three
following years made no mention of what we had transmitted. The reader
may imagine my uneasiness for the fate of a journal which contained
astronomical observations and barometrical measurements, of which I
had not made any copy. After having visited New Grenada, Peru and
Mexico, and just when I was preparing to leave the New Continent, I
happened, at a public library of Philadelphia, to cast my eyes on a
scientific Publication, in which I found these words: "Arrival of M.
de Humboldt's manuscripts at his brother's house in Paris, by way of
Spain!" I could scarcely suppress an exclamation of joy.
While M. Bonpland laboured day and night to divide and put our
collections in order, a thousand obstacles arose to impede our
departure. There was no vessel in the port of the Havannah that would
convey us to Porto Bello or Carthagena. The persons I consulted seemed
to take pleasure in exaggerating the difficulties of the passage of
the isthmus, and the dangerous voyage from Panama to Guyaquil, and
from Guyaquil to Lima and Valparaiso. Not being able to find a passage
in any neutral vessel, I freighted a Catalonian sloop, lying at
Batabano, which was to be at my disposal to take me either to Porto
Bello or Carthagena, according as the gales of Saint Martha might
permit.* (* The gales of Saint Martha blow with great violence at that
season below latitude 12 degrees.) The prosperous state of commerce at
the Havannah and the multiplied connections of that city with the
ports of the Pacific would facilitate for me the means of procuring
funds for several years. General Don Gonzalo O'Farrill resided at that
time in my native country as minister of the court of Spain. I could
exchange my revenues in Prussia for a part of his at the island of
Cuba; and the family of Don Ygnacio O'Farrill y Herera, brother of the
general, concurred kindly in all that could favour my new projects. On
the 6th of March the vessel I had freighted was ready to receive us.
The road to Batabano led us once more by Guines to the plantation of
Rio Blanco, the property of Count Jaruco y Mopox.
The road from Rio Blanco to Batabano runs across an uncultivated
country, half covered with forests; in the open spots the indigo plant
and the cotton-tree grow wild. As the capsule of the Gossypium opens
at the season when the northern storms are most frequent, the down
that envelops the seed is swept from one side to the other; and the
gathering of the cotton, which is of a very fine quality, suffers
greatly. Several of our friends, among whom was Senor de Mendoza,
captain of the port of Valparaiso, and brother to the celebrated
astronomer who resided so long in London, accompanied us to Potrero de
Mopox. In herborizing further southward, we found a new palm-tree with
fan-leaves (Corypha maritima), having a free thread between the
interstices of the folioles. This Corypha covers a part of the
southern coast and takes the place of the majestic palma real and the
Cocos crispa of the northern coast. Porous limestone (of the Jura
formation) appeared from time to time in the plain.
Batabano was then a poor village and its church had been completed
only a few years previously. The Sienega begins at the distance of
half a league from the village; it is a tract of marshy soil,
extending from the Laguna de Cortez as far as the mouth of the Rio
Xagua, on a length of sixty leagues from west to east. At Batabano it
is believed that in those regions the sea continues to gain upon the
land, and that the oceanic irruption was particularly remarkable at
the period of the great upheaving which took place at the end of the
eighteenth century, when the tobacco mills disappeared, and the Rio
Chorrera changed its course. Nothing can be more gloomy than the
aspect of these marshes around Batabano. Not a shrub breaks the
monotony of the prospect: a few stunted trunks of palm-trees rise like
broken masts, amidst great tufts of Junceae and Irides. As we stayed
only one night at Batabano, I regretted much that I was unable to
obtain precise information relative to the two species of crocodiles
which infest the Sienega. The inhabitants give to one of these animals
the name of cayman, to the other that of crocodile; or, as they say
commonly in Spain, of cocodrilo. They assured us that the latter has
most agility, and measures most in height: his snout is more pointed
than that of the cayman, and they are never found together. The
crocodile is very courageous and is said to climb into boats when he
can find a support for his tail. He frequently wanders to the distance
of a league from the Rio Cauto and the marshy coast of Xagua to devour
the pigs on the islands. This animal is sometimes fifteen feet long,
and will, it is said, pursue a man on horseback, like the wolves in
Europe; while the animals exclusively called caymans at Batabano are
so timid that people bathe without apprehension in places where they
live in bands. These peculiarities, and the name of cocodrilo, given
at the island of Cuba, to the most dangerous of the carnivorous
reptiles, appear to me to indicate a different species from the great
animals of the Orinoco, Rio Magdalena and Saint Domingo. In other
parts of the Spanish American continent the settlers, deceived by the
exaggerated accounts of the ferocity of crocodiles in Egypt, allege
that the real crocodile is only found in the Nile. Zoologists have,
however, ascertained that there are in America caymans or alligators
with obtuse snouts, and legs not indented, and crocodiles with pointed
snouts and indented legs; and in the old continent, both crocodiles
and gaviales. The Crocodilus acutus of San Domingo, in which I cannot
hitherto specifically distinguish the crocodiles of the great rivers
of the Orinoco and the Magdalena, has, according to Cuvier, so great a
resemblance to the crocodile of the Nile,* that it required a minute
examination to prove that the rule laid down by Buffon relative to the
distribution of species between the tropical regions of the two
continents was correct. (* This striking analogy was ascertained by M.
Geoffroy de Saint Hilaire in 1803 when General Rochambeau sent a
crocodile from San Domingo to the Museum of Natural History at Paris.
M. Bonpland and myself had made drawings and detailed descriptions in
1801 and 1802 of the same species which inhabit the great rivers of
South America, during our passage on the Apure, the Orinoco and the
Magdalena. We committed the mistake so common to travellers, of not
sending them at once to Europe, together with some young specimens.)
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