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mountains is found at the south-eastern extremity of the island, between Cabo Cruz, Punta Maysi and Holguin. - This mountainous district, called La Sierra or Las Montanas del Cobre, situated to the north-west of the city of Santiago de Cuba, appears to have an absolute elevation of more than 1200 toises. On this supposition the summits of the Sierra will be more lofty than those of the Blue Mountains of Jamaica or the peaks of La Selle and La Hotte of the Island of St. Domingo. The coasts of Xagua and of Batabano are very low, and I believe in general that there does not exist to the west of the meridian of Matanzas, with the exception of the Pan of Guaixabon, any hill more than 200 toises in height. In the interior of the island, the land, gently waving as in England, is only elevated about 45 or 60 toises above the surface of the ocean.
The decreasing level of the calcareous formations of the Island of Cuba indicates the submarine connexion of the same rocks with the equally low foundations of the Bahamas, Florida and Yucatan.
"Intellectual culture and instruction having been for a long time confined to the Havana and the circumjacent districts, we must not be surprised at the profound ignorance which prevails respectiug the geognosy of the Montanas del Cobre. A traveller, a pupil of M. Proust, well skilled in the sciences of chemistry and mineralogy, Don Francisco Ramirez, informs me that the west part of the island is granitic, and that he had there discovered gneiss and mica slate. It is probably from these granitic formations that have been derived those alluvions of auriferous sand which were explored with ardor in the early days of the conquest to the great misfortune of the natives. Traces of them are still found in the rivers of Holguin and Escambray, in the environs of Villa Clara, Santo Espiritu, Puerto del Principe, Bayamo, and la Bahia de Nipo. Perhaps the abundance of copper of which the Conquistadores of the sixteenth century speak, at an epoch when the Spaniards were more attentive to the natural productions of America than in later times, belong to the formations of amphibolic schist and transition slate mingled with diorite, and euphotide, of which I have found analogous beds in the mountains of Guanabacoa.
“ The central and western part of the island incloses two formations of compact limestone, one of argillaceous sandstone, and another of gypsum. The first of these calcareous formations offers, (I will not say by its location or superposition, which are unknown to me, but by its aspect and composition) some resemblance to the Jura limestone. It is white or of an ochre yellow, with an even texture-containing sometimes nodules of flint and petrifactions of pectens, cardites, terebratulas and madrepores, rather collected in particular banks, than dispersed through the whole mass. I have not found in it any beds of oolite, but many that are porous, almost vesicular, between the cattle-farm of the Count de Mopox and Batabano, similar to the spungy beds which the Jura limestone presents in Franconia near Dondorf, Pegnitz and Tumbach. This formation which I shall designate under the name of the limestone of Guines, to distinguish it from another much more recent forms, near Trinidad in the Lomas de St. Juan, steep peaks which recall to mind the calcareous mountains of Caripe in the environs
of Cumana. It encloses extensive caverns, but I know not that fossil bones have ever been found in it. I believe that the gypsum of the Island of Cuba belongs not to the tertiary but to secondary formations. It is found in several places to the east of Matanzas, at St. Antonio de los Baños, where it encloses sulphur, and in the Cays, near St. Juan de los Remedios. We must not confound with this limestone of Guines sometimes porous, sometimes compact, another formation so recent that we may readily believe that it increases even in our own days. I mean those calcareous agglomerates that I have seen in the Keys or Islets wbich border the coast between Batabano and the Bay of Xagua. The lead proves that there are rocks that rise abruptly from a bottom of twenty or thirty fathom, some appear even with the water, uthers two or three feet above the surface. Angular fragments of madrepore and of other zoophytes of two or three cubic inches in size are found cemented in them by fine grains of quartz. All the inequalities of these rocks are covered with a moveable soil, (terrain de rapport) in which, with the microscope, we can distinguish nothing but the detritus of shells and corals. This tertiary formation belongs, without doubt, to that of the coasts of Cumana, of Carthagena, of Guadaloupe. It is the formation of Coralline Islands of the South-Sea, on which Messrs. Chamisso and Guaimard have recently thrown so much light.
“ Without wishing to assign with certainty in the table of formations a determinate place to the limestone of Guines, we entertain no doubt of the relative antiquity of this rock, when compared with the calcareous agglomerate of the Keys, situate to the south of Batabanos, and to the east of the Isle of Pines. The globe has undergone great revolutions between the epochs when these two beds were formed, the one inclosing the great Caverns of Matanzas, the other augmenting daily by the agglutination of fragments of coral and of quartzose sand. The more recent of these beds seem to rest to the south of Cuba, sometimes on the limestone of Guines, (as in the Jardinillos) sometimes (near Cape Cruz) immediately on primitive rocks. In the Little Antilles, the corals have even enveloped volcanic products.
“ To the east of the Havana, the secondary formations are pierced in a very remarkable manner by rocks of syenite and euphotide grouped together. The southern and northern shores of the harbour, the hills of the Morro and of la Cabana are of the limestone of Guines, but on the eastern border of the Ensenadas de Regla and of Guanabacoa, all the rocks belong to the transition series. In going to the south, there appears on the surface, at first, near Marimelene, syenite, composed of much amphibole, partly decomposed, a little quartz, and a pale red feldspath' rarely cristallized. This handsome syenite alternates twice with serpentine. The interposing beds of serpentine are about eighteen or twenty feet thick.
Farther to the south, towards Regla aud Guanabacoa, the syenite disappears, and all the surface is covered with serpentine, which rises in hills of 30 or 40 toises in height, running from east to west. This rock splits easily, and is traversed by small veins of asbestus. It contains not garnet or amphibole, but metalloidal diallage disseminated through the mass--and it was the first time I found this variety of diallage within the tropics. Many blocks of serpentine have
magnetic poles, and others have a texture so homogeneous, and a lustre so ylistening or oily, that at a distance it would be taken for pitchstone. It is desirable that these fine masses should be employed in the arts as is done in many parts of Germany. Petroleum oozes out in some places from the fissures of the serpentine.
There has not yet been discovered in the Island of Cuba, volcanic rocks of a recent period, such for example as trachytes, dolerites and basalts. I am even ignorant if they are found in any of the great Antilles, of which the geognostic constitution differs essentially from that of the series of calcareous aud volcanic isles which extend from Trinidad to the Virgiu Islands.” Vol. 1. pp. 45–66.
We have given this extract, long, even though greatly curtailed, because we rarely meet with a geological view of the Autilles on which we can place dependence. We doubt, however, if the geognostic constitution of the great and lesser Antilles essentially differs. In all from which we have scen specimens, the foundation rock appears to be syenite, with a great preponderance of amphibole. With this is intermingled other primitive rocks as gneiss, mica slate, &c. and over them are deposited the two calcareous formations described by Humboldt, and perhaps an intermediate one, in which the beautiful siliceous petrifactions of Antigua, Guadaloupe and other islands may be arranged.
When speaking of the discovery of gold in Cuba and St. Domingo at the time of the conquest, which appears to have been found and chiefly obtained by washing from alluvial soils, Humbolút enters into some details on the subject. It appears from Herrera, that in his day, the king's fifth in the Island of Cuba was valued at 6000 pesos, which would indicate an annual produce of 2000 marcs of gold. In 1804, all the mines of Mexico yielded but 7000 marcs of gold, those of Peru, 3,400. In recent attempts to renew the washings for gold in Cuba and Hayti, the products have been very inconsiderable ; for this we think our author gives very satisfactory reasons, and when we learn, in addition, that in Brazil the produce of gold washings decreased in sixty years between 1760 and 1820, from 6600 kilograms of gold to less than 595, we may well suppose that the known localities in Cuba were exhausted before they were abandoned by the first discoverers. Within the last two years, however, as
A spring of liquid bitumen, which is supposed to have dried up, first attracted Ocampo, who used it instead of pitch in careenin: his vessels, to the port of Havana, and caused its settlement under the name of Puerto de Carenas. In the eastern part of the island many springs of petroleum are found, and recently there has been discovered near the Punta Icacos a small islet, (Siguapa) whose surface offers no other soil than a solid earthy bitumen.
+ Humboldt appears to consider the gold district of Carolina of which the limits appear to be widening every day as belonging to the same formation [?] as that of the Antilles.
if to exeite anew the attention of its inhabitants to the search of mineral treasures, a mine of silver has been discovered near Villa Clara, which is said by the discoverer to cover a considerable extent of ground, and by the assayers to contain, (mingled with an oxyd of iron, and resembling a great many of the ores of Peru,) a portion of silver, which, in South-America, would entitle it to be considered as a very
Several veins of copper have also been discovered in the same district, and it would appear from the interesting journal we quote* that some attention has been excited by these discoveries.
From the sketch we have given, it will not create any surprise to learn how destitute of rivers this magnificent island is found to be. Its breadth, or to speak more accurately, its want of breadth forbids their existence. Many small streams descend from the bills and hurry to the ocean; but in the season of drought, some of these become dry, and others furnish but scanty rills. Indeed, if the improvement and cultivation of Cuba should continue to advance in such rapid progression as it has done for the last twenty years, it is not improbable that all of her streams will be employed and exhausted in the irrigation of the plains, for, as we have already intimated,t in all tropical climates the value of land employed in raising the sugar cane, is incalculably increased by the acquisition of the means of irrigation. It may, perhaps, be said that water is the greatest want felt in this island. Few permanent springs exist, and in many places wells are dug from 150 to 300 feet deep through solid limestone before water can be obtained. Its quality, however, is good, but the expense of sinking these wells is so great that few planters encounter this apparently necessary part of their establishment until they have ascertained that the soil of their plantations is rich, arable and productive. They submit to the inconvenience of employing an ox cart constantly to bring from the nearest stream or farm, their daily supply of water. Indeed as the island has been more and more deprived of its forests, the annual fall of rain is supposed to diminish.
6. The climate of the Havana,” says our author, “is that which corresponds to the extreme limit of the torrid zone. It is a tropical climate, in which a more unequal distribution of heat between the different parts of the year announces already the passage to the climates of the temperate zone.” The discussion of climates is a favourite topic with Humboldt, and is not forgotten in his account of Cuba. We shall briefly notice from him the facts that seem to be most important, and the * Anales de Ciencias, Agricultura, &c.—May & October, 1828. January, 1829.
Southern Review, No. 6-p. 336.
comparisons which he has made of the temperature of the Havana with other cities in different quarters of the globe. The mean temperature of the Havana is, after four years of good observation, 25. 7 of the centigrade thermometer, (78 Fahrenheit) only two degrees lower than that of Comana, so much nearer to the equator. The proximity of the ocean elevates along the coast the mean temperature of the year; but in the interior of the island where the north winds penetrate with equal force, and the soil is elevated to the small height of 240 or 250 feet, the mean temperature only reaches 23.6. (73.4 F.) and does not surpass that of Cairo and Lower Egypt. The difference between the mean temperature of the warmest and the coldest month in the interior of the island, amounts to 12° (21.6 F.); on the coast to 8° (14.4 F.); at Cumana scarcely to 3 (5.4 F.) In the warmest months (July and August) the mean temperature reaches 28 to 290 (82 to 84 F.) as under the equator. In the coldest months (December and January) the temperature is in the interior 17o (62. 6 F.); at the Havana 21° (69.8 F.) three degrees higher (5.4 F.) than the warmest month at Paris. One peculiarity which has been frequently noticed when comparing temperatures, may yet be mentioned—it is, that the thermometer often attains a higher point at places far removed from the equator, than at the equator itself. Thus, for instance, the thermometer does not rise at Cumana but to 33° (91.5 F.); at Vera Cruz in thirteen years it was only once to 32 (89. 6 F.); at the Havana in three years, M. Ferrer has only seen it range between 16 and 30° (60.8 and 86 F.) It was noticed as a remarkable fact by M. Robredo, that in 1801 the mercury rose to 34.4 (94 F.) wbile at Paris, according to the observations of M. Arago, the Mercury four times in ten years, (between 1793 and 1-03) rose to 36.7 and 38° (97.5 and 100 F.) and the registers of our northern cities will corroborate this statement. Ice has been seen in Cuba, but it is known that by the effect of radiation, this will sometimes be produced when the thermometer is 9 to 12- Fahrenheit, above the point of congelation. Hail, wbich at Macao, in nearly the same latitude, falls very frequently and very large, does not occur at the Havana above once in fifteen years. Snow is never seen.
The occasional fall of the temperature in Cuba, though sometimes considerable, is yet of so short a duration that neither the banana, the sugar cane, nor the other productions of the torrid zone, suffer habitually from it. It is known that plants which enjoy a vigorous organization, resist easily a slight cold-the VOL. IV.--N0. 8.