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Paris. Its length from Cape St. Antonio to Cape Maysi along a line slightly curved, is 227 marine leagues, equal to 783 English miles. Its greatest width from Point Maternillo to the Pico de Tarquino is 37 leagues or 127 miles; its mean breadth is 15 leagues or nearly 52 miles, while opposite the Havana it is narrowed to a space not exceeding 83 leagues or 274 miles, and from the Havana to Cape Antonio, with some occasional dilatation, it gradually contracts to a point. The circumference is 520 leagues or 1794 miles, indented with a great number of fine bays or harbours. Nearly fifty are enumerated, some of which possess every advantage that a naval port can require. As the coast for nearly two-thirds of its extent is surrounded by reefs and banks, so as to be approached with difficulty, it was but imperfectly known, and until the surveys made under the direction of the government of Spain by Don Jose del Rio and Don Ventura de Barcaiztequi, near the close of the last century and the beginning of the present, the real magnitude of this island was imperfectly ascertained, and was usually overrated. It has been found by very careful admeasurements made by M. Bauza, under the direction of M. Humboldt, to contain, including the Isle of Pines on its southern coast, 3,615 square marine leagues, equal to 43,092* square English miles, and bears in size the following relation to other well-known territories. England, exclusive of Wales,

50,000 Portugal,

40,000 Virginia,

68,000 Pennsylvania,

44,000 Ohio,

40,000
Ireland,

32,000
Java,
Cuba,

43,000
Hayti,

29,204 Jamaica,

5,483 The surface of Cuba is beautifully undulated, and while the hills seldom rise too high for profitable culture or pasture, the level lands sink only in one district along the southern coast between Batabano and Xagua, or perhaps Trinidad, so low as to become swampy or miry. The greater portion of the island, however, may be considered as level, though elevated about two or three hundred feet above the level of the ocean, and sufficiently broken for all the purposes of health and convenience. A range of hills traverses the island longitudinally, and the land, in general, gradually slopes on each side from their summits to

* It was formerly estimated by Geographers at 52 and 53,000 square miles,

the ocean.

From Cape Antonio to a small distance east of Matanzas, these hills approach the northern coast, rarely exceeding 7 or 800 feet in height, and in some places, scarcely perceptible as a distinct range; opposite the Havana, when it was proposed a few years ago to unite the harbour of that city with the port of Batabano on the southern coast, it was found that the intervening land did not exceed, on two different lines in which it was proposed to locate the canal, the height of 200 feet. To the east of Matanzas, around which the country is broken and rocky, the land appears to become lower and more level, but the bills soon appear on the southern side of the island, and are of moderate height until they reach the meridian of Cabo del Cruz, when they begin to attain a lofty altitude, and under the general pame of Sierra de Cobre, or Copper Mountains, though with other local denominations to particular portions, continue for nearly two hundred miles to Cape Maysi. The summits of soine of these mountains are seven thousand feet high, and give to the eastern part of Cuba a scenery more picturesque and magnificent, tban belongs to the other portions of this island.

The geological structure of Cuba we shall briefly notice, because on this subject the gleanings of such an observer as Humboldt, whom we shall follow in this article when not otherwise expressed, merit notice. We shall condense as much as possible his observations, which he often carries too much into detail, without those generalizations which, perhaps, the state of the science will not yet permit to be accurately and absolutely made. General views, however, are gratifying to the inquirer, and useful when offered in their legitimate form, not as established axioms of science, but as approximations such as our present knowledge will permit us to propose, and intended to serve rather as propositions to provoke and direct our researches and speculations, than as dogmas to control our faith. Few, we believe, would ever have patience to wade through a volume of mere geological statements, viewed as an unconnected series of detached and isolated facts, if neither writer nor reader had adopted any principle to guide his investigations, or to arrange the materials which he may casually acquire.

« The Island of Cuba in more than four-fifths of its extent, offers only a low and level surface. It is a soil covered with secondary and tertiary formations through which appear some rocks of gneiss, of sye. nite, and of euphotide. We do not yet possess any exact notions of the geogoostic configuration of the country, or of the relative age and the nature of its strata. We only know that the most elevated group of

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 bill more than 200 toises in height. In the interior of the island, the land, gently waying 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 respecting 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, pear 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 terriary 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 which border the corist 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, úthers 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 quarız. All the inequalities of these rocks are covered with a moveable sol, (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 barbour, 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 tra'isition 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 and 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 glistening 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 ignoraut if they are found in any of the great Antilles, of which the geognostic constitution differs essentially from that of the series of calcareous and volcanic isles which extend from Trinidad to the Virgin 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 Antilles 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 seen specimens, the foundation rock appears to be syenite, with a great preponderance of amphibole. With this is intermingled other priinitive 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, Humboldt 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 discovererset 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 careening 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 inany 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.

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