198 Scientific Intelligence. — Geologij. 



the crystals had a purplish tint, a trace of muriate of cobalt was 

 detected. From the observations made by the author at diffe- 

 rent periods, he concludes, that the dense white smoke which 

 rose in immense columns from the stream of lava, and which re- 

 flected the morning and evening hght of the purest tints of red 

 and orange, was produced by the salts which were sublimed 

 with the steam. It presented a striking contrast to the black 

 smoke arising from the crater, which was loaded with earthy 

 particles, and which, in the night, was highly luminous at the 

 moment of the explosion. The phenomena observed by the 

 author afford a sufficient refutation of all the ancient hypotheses, 

 in which volcanic fires were ascribed to such chemical causes, as 

 the combustion of mineral coal, or the action of sulphur upon 

 iron ; and are perfectly consistent with the supposition of their 

 depending upon the oxidation of the metals of the earths upon 

 an extensive scale, in immense subterranean cavities, to which 

 water, or atmospheric air, may occasionally have access. The 

 subterranean thunder heard at great distances under Vesuvius, 

 prior to an eruption, indicates the vast extent of these cavities; 

 and the existence of a subterranean communication between the 

 Solfatara and Vesuvius, is established by the fact that, when- 

 ever the latter is in an active state, the former is comparatively 

 tranquil. In confirmation of these views the author remarks, 

 that almost all volcanoes of considerable magnitude in the old 

 world are in the vicinity of the sea; and, in those where the sea 

 is more distant, as in the volcanoes of South America, the wa- 

 ter may be supplied from great subterranean lakes ; for Hum- 

 boldt states, that some of them throw up quantities of fish. The 

 author acknowledges, however, that the hypothesis of the nu- 

 cleus of the globe being composed of matter liquefied by heat, 

 offers a still more simple solution of the phenomena of volcanic 

 fires. 



27. Fossil Rib of a Whale, discovered in Diluvium near Kemp 

 Town, Brighton. — A short time since, a man employed in col- 

 lecting stones from the beach, near Black-Rock, observed a huge 

 body projecting from the base of the cliff"; after satisfying him- 

 self of its nature, by breaking off' a large mass of it, he covered 

 the spot with a heap of sand, and informed the Rev. Mr W^al- 

 lace of Brighton of the discovery. Mr W. transmitted the in- 

 telligence to Mr Mantell of Castle Place, in this town (a gentle- 



