This Noise Explains The Phenomena Of The Baxos Roncadores (Snoring Bocabeoos), So Well Known To Navigators Who Cross From Jamaica

To the mouth of Rio San Juan of Nicaragua, or to the island of San Andres.) We are at first

Tempted to admit that the whole of this limestone rock, which constitutes the principal portion of the island of Cuba, may be traced to an uninterrupted operation of nature - to the action of productive organic forces - an action which continues in our days in the bosom of the ocean; but this apparent novelty of limestone formations soon vanishes when we quit the shore, and recollect the series of coral rocks which contain the formations of different ages, the muschelkalk, the Jura limestone and coarse limestone. The same coral rocks as those of the Castillo and La Punta are found in the lofty inland mountains, accompanied with petrifications of bivalve shells, very different from those now seen on the coasts of the Antilles. Without positively assigning a determinate place in the table of formations to the limestone of Guines, which is that of the Castillo and La Punta, I have no doubt of the relative antiquity of that rock with respect to the calcareous agglomerate of the Cayos, situated south of Batabano, and east of the island of Pinos. The globe has undergone great revolutions between the periods when these two soils were formed; the one containing the great caverns of Matanzas, the other daily augmenting by the agglutination of fragments of coral and quartzose sand. On the south of the island of Cuba, the latter soil seems to repose sometimes on the Jura limestone of Guines, as in the Jardinillos, and sometimes (towards Cape Cruz) immediately over primitive rocks. In the lesser Antilles the corals are covered with volcanic productions. Several of the Cayos of the island of Cuba contain fresh water; and I found this water very good in the middle of the Cayo de Piedras. When we reflect on the extreme smallness of these islands we can scarcely believe that the fresh-water wells are filled with rain-water not evaporated. Do they prove a submarine communication between the limestone of the coast with the limestone serving as the basis of lithophyte polypi, and is the fresh water of Cuba raised up by hydrostatic pressure across the coral rocks of Cayos, as it is in the bay of Xagua, where, in the middle of the sea, it forms springs frequented by the lamantins?

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.

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