To Comprehend The Cordillera Of Venezuela In Mass We Must Carefully Study The Direction And Windings Of The Coast From Punta Tucacas (West Of Porto Cabello) As Far As Punta De La Galera Of The Island Of Trinidad.

That island, those of Los Testigos, Marguerita and Tortuga constitute, with the mica-slates of the peninsula of Araya, one and the same system of mountains.

The granitic rocks which appear between Buria, Duaca and Aroa cross the valley of the Rio Yaracui and draw near the shore, whence they extend, like a continuous wall, from Porto Cabello to Cape Codera. This prolongation forms the northern chain of the Cordillera of Venezuela and is traversed in going from south to north, either from Valencia and the valleys of Aragua, to Burburata and Turiamo, or from Caracas to La Guayra. Hot springs* issue from those mountains (* The other hot springs of the Cordillera of the shore are those of San Juan, Provisor, Brigantin, the gulf of Cariaco, Cumucatar and Irapa. MM. Rivero and Boussingault, who visited the thermal waters of Mariara in February, 1823, during their journey from Caracas to Santa Fe de Bogota, found their maximum to be 64 degrees centigrade. I found it at the same season only 59.2 degrees. Has the great earthquake of the 26th March, 1812, had an influence on the temperature of these springs? The able chemists above mentioned were, like myself, struck with the extreme purity of the hot waters that issue from the primitive rocks of the basin of Aragua. Those of Onoto, which flow at the height of 360 toises above the level of the sea, have no smell of sulphuretted hydrogen; they are without taste, and cannot be precipitated, either by nitrate of silver or any other re-agent. When evaporated they have an inappreciable residue which consists of a little silica and a trace of alkali; their temperature is only 44.5 degrees, and the bubbles of air which are disengaged at intervals are at Onoto, as well as in the thermal waters of Mariara, pure nitrogen. The waters of Mariara (244 toises) have a faint smell of sulphuretted hydrogen; they leave, by evaporation, a slight residuum, that yields carbonic acid, sulphuric acid, soda, magnesia and lime. The quantities are so small that the water is altogether without taste. In the course of my journey I found only the springs of Cumangillas hotter than the thermal waters of Las Trincheras: they are situated on the south of Porto Cabello. The waters of Comangillas are at the height of 1040 toises and are alike remarkable for their purity and their temperature of 96.3 degrees centigrade.), those of Las Trincheras (90.4 degrees) on its southern slope and those of Onoto and Mariara on its southern slope. The former issue from a granite with large grains, very regularly stratified; the latter from a rock of gneiss. What especially characterizes the northern chain is a summit which is not only the loftiest of the system of the mountains of Venezuela, but of all South America, on the east of the Andes.

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