- Martinique, Three Great Extinguished Volcanoes; Vauclin, The Paps Of Carbet, Which Are Perhaps The Most Elevated Summits Of The Smaller Islands, And Montagne Pelee.

(The height of this last mountain is probably 800 toises; according to Leblond it is 670 toises; according to Dupuget, 736 toises.

Between Vauclin and the feldspar-lavas of the Paps of Carbet is found, as M. Moreau de Jonnes asserts, in a neck of land, a region of early basalt called La Roche Carree). Thermal waters of Precheur and Lameutin. - Dominica, completely volcanic. - Guadaloupe, an active volcano, the height of which, according to Leboucher, is 799 toises; according to Amie, 850 toises. - Montserrat, a solfatara; fine porphyritic lavas with large crystals of feldspar and hornblende near Galloway, according to Mr. Nugent. - Nevis, a solfatara. - St. Christopher's, a solfatara at Mount Misery. - St. Eustache, a crater of an extinguished volcano, surrounded by pumice-stone. (Trinidad, which is traversed by a chain of primitive slate, appears to have anciently formed a part of the littoral chain of Cumana, and not of the system of the mountains of the Caribbee Islands.)) Each island is not the effect of one single heaving-up: most of them appear to consist of isolated masses which have been progressively united together. The matter has not been emitted from one crater, but from several; so that a single island of small extent contains a whole system of volcanoes, regions purely basaltic, and others covered with recent lavas. The volcanoes still burning are those of St. Vincent, St. Lucia, and Guadaloupe. The first threw out lava in 1718 and 1812; in the second there is a continual formation of sulphur by the condensation of vapours, which issue from the crevices of an ancient crater. The last eruption of the volcano of Guadaloupe took place in 1797. The Solfatara of St. Christopher's was still burning in 1692. At Martinique, Vauclin, Montagne Pelee, and the crater surrounded by the five Paps of Carbet, must be considered as three extinguished volcanoes. The effects of thunder have been often confounded in that place with subterranean fire. No good observation has confirmed the supposed eruption of the 22nd of January, 1792. The group of volcanoes in the Caribbee Islands resembles that of the volcanoes of Quito and Los Pastos; craters with which the subterranean fire does not appear to communicate are ranged on the same line with burning craters, and alternate with them.

Notwithstanding the intimate connection manifested in the action of the volcanoes of the smaller West India Islands and the earthquakes of Terra Firma, it often happens that shocks felt in the volcanic archipelago are not propagated to the island of Trinidad, or to the coasts of Caracas and Cumana. This phenomenon is in no way surprising: even in the Caribbees the commotions are often confined to one place. The great eruption of the volcano in St. Vincent's did not occasion an earthquake at Martinique or Guadaloupe. Loud explosions were heard there as well as at Venezuela, but the ground was not convulsed.

These explosions must not be confounded with the rolling noise which everywhere precedes the slightest commotions; they are often heard on the banks of the Orinoco, and (as we were assured by persons living on the spot) between the Rio Arauca and Cuchivero. Father Morello relates that at the Mission of Cabruta the subterranean noise so much resembles discharges of small cannon (pedreros) that it has seemed as if a battle were being fought at a distance. On the 21st of October, 1766, the day of the terrible earthquake which desolated the province of New Andalusia, the ground was simultaneously shaken at Cumana, at Caracas, at Maracaybo, and on the banks of the Casanare, the Meta, the Orinoco, and the Ventuario. Father Gili has described these commotions at the Mission of Encaramada, a country entirely granitic, where they were accompanied by loud explosions. Great fallings-in of the earth took place in the mountain Paurari, and near the rock Aravacoto a small island disappeared in the Orinoco. The undulatory motion continued during a whole hour. This seemed the first signal of those violent commotions which shook the coasts of Cumana and Cariaco for more than ten months. It might be supposed that men living in woods, with no other shelter than huts of reeds and palm-leaves, could have little to dread from earthquakes. But at Erevato and Caura, where these phenomena are of rare occurrence, they terrify the Indians, frighten the beasts of the forests, and impel the crocodiles to quit the waters for the shore. Nearer the sea, where shocks are frequent, far from being dreaded by the inhabitants, they are regarded with satisfaction as the prognostics of a wet and fertile year.

In this dissertation on the earthquakes of Terra Firma and on the volcanoes of the neighbouring archipelago of the West India Islands, I have pursued the plan of first relating a number of particular facts, and then considering them in one general point of view. Everything announces in the interior of the globe the operation of active powers, which, by mutual reaction, balance and modify one another. The greater our ignorance of the causes of these undulatory movements, these evolutions of heat, these formations of elastic fluids, the more it becomes the duty of persons who apply themselves to the study of physical science to examine the relations which these phenomena so uniformly present at great distances apart. It is only by considering these various relations under a general point of view, and tracing them over a great extent of the surface of the globe, through formations of rocks the most different, that we are led to abandon the supposition of trifling local causes, strata of pyrites, or of ignited coal.* (* See "Views of Nature" - On the structure and action of volcanoes in different parts of the world, page 353 (Bohn's edition); also "Cosmos" pages 199-225 (Bohn's edition).)

The following is the series of phenomena remarked on the northern coasts of Cumana, Nueva Barcelona, and Caracas; and presumed to be connected with the causes which produce earthquakes and eruptions of lava.

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