Personal Narrative Of Travels To The Equinoctial Regions Of America During The Years 1799-1804 - Volume 3 - By Alexander Von Humboldt And Aime Bonpland.
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These Considerations,
Suggested By The History Of The Conquest, And By The Science Of
Mining, May Throw Some Light On The Problem Of The Metallic Wealth Of
Hayti.
In that island, as well as at Brazil, it would be more
profitable to attempt subterraneous workings (on veins)
In primitive
and intermediary soils than to renew the gold-washings which were
abandoned in the ages of barbarism, rapine and carnage.); traces of
that sand are still found in the rivers Holguin and Escambray, known
in general in the vicinity of Villa-Clara, Santo Espiritu, Puerto del
Principe de Bayamo and the Bahia de Nipe. The abundance of copper
mentioned by the Conquistadores of the sixteenth century, at a period
when the Spaniards were more attentive than they have been in latter
times to the natural productions of America, may possibly be
attributed to the formations of amphibolic slate, transition
clay-slate mixed with diorite, and to euphotides analogous to those I
found in the mountains of Guanabacoa.
The central and western parts of the island contain two formations of
compact limestone; one of clayey sandstone and another of gypsum. The
former has, in its aspect and composition, some resemblance to the
Jura formation. It is white, or of a clear ochre-yellow, with a dull
fracture, sometimes conchoidal, sometimes smooth; divided into thin
layers, furnishing some balls of pyromac silex, often hollow (at Rio
Canimar two leagues east of Matanzas), and petrifications of pecten,
cardites, terebratules and madrepores.* (* I saw neither gryphites nor
ammonites of Jura limestone nor the nummulites and cerites of coarse
limestone.) I found no oolitic beds, but porous beds almost bulbous,
between the Potrero del Conde de Mopox, and the port of Batabano,
resembling the spongy beds of Jura limestone in Franconia, near
Dondorf, Pegnitz, and Tumbach. Yellowish cavernous strata, with
cavities from three to four inches in diameter, alternate with strata
altogether compact,* and poorer in petrifications. (* The western part
of the island has no deep ravines; and we recognize this alternation
in travelling from the Havannah to Batabano, the deepest beds
(inclined from 30 to 40 degrees north-east) appear as we advance.) The
chain of hills that borders the plain of Guines on the north and is
linked with the Lomas de Camua, and the Tetas de Managua, belongs to
the latter variety, which is reddish white, and almost of lithographic
nature, like the Jura limestone of Pappenheim. The compact and
cavernous beds contain nests of brown ochreous iron; possibly the red
earth (tierra colorada) so much sought for by the coffee planters
(haciendados) owes its origin to the decomposition of some superficial
beds of oxidated iron, mixed with silex and clay, or to a reddish
sandstone* (* Sandstone and ferruginous sand; iron-sand?) superposed
on limestone. The whole of this formation, which I shall designate by
the name of the limestone of Guines, to distinguish it from another
much more recent, forms, near Trinidad, in the Lomas of St. Juan,
steep declivities, resembling the mountains of limestone of Caripe, in
the vicinity of Cumana. They also contain great caverns, near Matanzas
and Jaruco, where I have not heard that any fossil bones have been
found. The frequency of caverns in which the pluvial waters
accumulate, and where small rivers disappear, sometimes causes a
sinking of the earth. I am of opinion that the gypsum of the island of
Cuba belongs not to tertiary but to secondary soil; it is worked in
several places on the east of Matanzas, at San Antonio de los Banos,
where it contains sulphur, and at the Cayos, opposite San Juan de los
Remedios. We must not confound with this limestone of Guines,
sometimes porous, sometimes compact, another formation so recent that
it seems to augment in our days. I allude to the calcareous
agglomerates, which I saw in the islands of Cayos that border the
coast between the Batabano and the bay of Xagua, principally south of
the Cienega de Zapata, Cayo Buenito, Cayo Flamenco and Cayo de
Piedras. The soundings prove that they are rocks rising abruptly from
a bottom of between twenty and thirty fathoms. Some are at the water's
edge, others one-fourth or one-fifth of a toise above the surface of
the sea. Angular fragments of madrepores, and cellularia from two to
three cubic inches, are found cemented by grains of quartzose sand.
The inequalities of the rocks are covered by mould, in which, by help
of a microscope, we only distinguish the detritus of shells and
corals. This tertiary formation no doubt belongs to that of the coast
of Cumana, Carthagena, and the Great Land of Guadaloupe, noticed in my
geognostic table of South America.* (* M. Moreau de Jonnes has well
distinguished, in his Histoire physique des Antilles Francoises,
between the Roche a ravets of Martinique and Hayti, which is porous,
filled with terebratulites, and other vestiges of sea-shells, somewhat
analogous to the limestone of Guines and the calcareous pelagic
sediment called at Guadaloupe Platine, or Maconne bon Dieu. In the
cayos of the island of Cuba, or Jardinillos del Rey y del Reyna, the
whole coral rock lying above the surface of the water appeared to me
to be fragmentary, that is, composed of broken blocks. It is, however,
probable, that in the depth it reposes on masses of polypi still
living.) MM. Chamiso and Guiamard have recently thrown great light on
the formation of the coral islands in the Pacific. At the foot of the
Castillo de in Punta, near the Havannah, on shelves of cavernous
rocks,* covered with verdant sea-weeds and living polypi, we find
enormous masses of madrepores and other lithophyte corals set in the
texture of those shelves. (* The surface of these shelves, blackened
and excavated by the waters, presents ramifications like the
cauliflower, as they are observed on the currents of lava. Is the
change of colour produced by the waters owing to the manganese which
we recognize by some dendrites? The sea, entering into the clefts of
the rocks, and in a cavern at the foot of the Castillo del Morro,
compresses the air and makes it issue with a tremendous noise.
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