branner: the stone reefs of brazil. 179 



appearance of a fog in the vicinity of the rock, and upon visiting it they 

 found " the sea all about the rock boiled, and that the supposed fog was 

 the smoke or vapour that rose from it." After about five years the fog 

 cleared avvay^ and fire and smoke were seen issuing from, a peak upon the 

 island. At the time of Langsdorflf's visit in 1806, the lava was still 

 running from the island into the sea, and the sides of the peak were 

 hot.^ These and other cases of submarine eruptions are cited by Scrope.^ 

 Mr. W. G. Foster of Zante, Greece, has also called attention to evidences 

 of submarine eruptions afforded by the burning of submarine cables.' 

 These eruptions did not reach the surface of the seas. Dr. Sambon tells 

 of the breaking of cables by submarine eruptions on several different 

 occasions, of the boiling of the sea, and of the escape of gases * through 

 the sea-water. 



Sainte-Claire Deville ^ found carbonic acid emerging lower down on 

 Vesuvius than ammoniacal gases, toward the end of an active period of 

 eruption, and always cold. He considers these discharges as an effect 

 and as the last act of eruptions. 



Fouque's later and more extended studies " confirm the law of the 

 variation of volcanic gases first established by Ch. Sainte-Claire Deville." * 

 He also found that the law in regard to the order of discharge of the 

 various gases is the same for submarine as for subaerial volcanoes.' By 

 direct observation he ascertained that from 4 to 88 per cent of the gases 

 obtained from the fumaroles of Santorin were carbonic acid.* This gas 

 escapes even when volcanic activity is dormant, and in some cases accu- 

 mulates in considerable quantities in depressions such as the Valley of 

 Death in Java, where animals are often suffocated. " In Java there is a 

 crater, called the ' Guevo Upas,' or ' Poison Valley,' half a mile in cir- 

 cumference, always so full of carbonic acid gas that every living thing 

 that passes its limits is suffocated, and the ground is strewed with the 



1 G. H. von Langsdorff. Voyages and travels in various parts of the world, 

 Part II., p. 242-245. London, 1814. 



W. H. Dall. A new volcanic island in Alaska. Science, Jan. 25, 1884, III , 

 p. 89-93. 



I.C.Russell. Volcanoes of North America, p. 276-281. New York, 1897. 

 Kotzebue's Voyage of discovery, Vol. III., p. 287. London, 1821. 



2 G. Poulett Scrope. Volcanoes, ed. 2, p. 236-238, London, 1862. 



3 Trans. Seismological Society of Japan, Vol. XV., p. 73. Yokohama, 1890. 



* L. Sambon. Notes on the Eolian Islands and on pumice stone. The South 

 Italian volcanoes. Edited by H. J. Jolinston-Lavis. p. 64-65. Naples. 1891. 

 5 Bull. Soc. Ge'ol. de France, XIII. ser. 2, p. 640. Paris. 1855-6. 

 ^ F. Fouque. Santorin et ses eruptions, p. 232. Paris, 1870. 

 ' Op. cit., p. viii. 8 Qp, cit., p. 225. 



