204 COSMOS. 



terminate directions.* There is no portion of the earth, 

 where hot springs, salse?, and gas eruptions occur, that has 

 been made the subject of such admirable and complete chem- 

 ical investigations as those on Iceland, which we owe to the 

 acute and persevering exertions of Bunsen. Nowhere, per- 

 haps, in such a great extent of country, or so near the sur- 

 face, is such a multifarious spectacle of chemical decomposi- 

 tions, conversions, and new formations to be witnessed. 



Passing from Iceland to the neighboring American conti- 

 nent, we find in the State of New York, in the neighborhood 

 of Fredonia, not far from Lake Erie, a multitude of jets of 

 inflammable gas (carbureted hydrogen) breaking forth from 

 fissures in a basin of Devonian sandstone strata, and partly 

 employed for the purpose of illumination. Other springs 

 of inflammable gas, near Rushville, assume the form of mud 

 cones; and others, in the valley of the Ohio, in Virginia, 

 and on the Kentucky River, also contain chlorid of sodium, 

 and are there connected with weak naphtha springs. But 

 on the other side of the Caribbean Sea, on the north coast 

 of South America, 11^ miles south-southeast from the har- 

 bor of Cartagena de Indias, near the pleasant village of Tur- 

 baco, a remarkable group of salses or mud volcanoes exhibits 

 phenomena which I was the first to describe. 



In the neighborhood of Turbaco, where one enjoys a mag- 

 nificent view of the colossal snowy mountains (Siei-ras Ifera- 

 das) of Santa Marta, on a desert spot in the midst of the 

 primeval forest, rise the Yolcancitos^ to the number of 18 or 

 20. The largest of the cones, which consist of blackish 

 gray loam, are from 19 to 23 feet in height, and probably 

 80 feet in diameter at the base. At the apex of each cone 

 is a circular orifice of 20 to 28 inches in diameter, surround- 

 ed by a small mud wall. The gas rushes up with great vio- 

 lence, as in Taman, forming bubbles, each of which, accord- 

 ing to my measurements in graduated vessels, contains 10 

 12 cubic inches. The upper part of the funnel is filled with 

 water, which rests upon a compact floor of mud. The 

 eruptions are not simultaneous in neighboring cones, but in 

 each one a certain regularity was observable in the periods 

 of the eruptions. Bonpland and I, standing on the outer- 

 most parts of the groups, counted pretty regularly five erup- 

 tions every two minutes. On bending down over the small 

 orifice of the crater a hollow sound is perceived in the in- 

 terior of the earth, far below the base of the cone, usually 



* \Valtersh ansen. op. rit.. s, 118. 



