CALCAREOUS SPRINGS. 213 



This skeleton appears, from the craniological developments, tq 

 have belonged to a Peruvian, or to some orie of a similar race, 

 being entirely dissimilar to the skulls of the Caribs, or ancient 

 possessors of the island. Another skeleton in a sitting posture is 

 in the museum at Paris. The formation of this limestone is as 

 follows. The sea which surrounds the Bermudas, abounds in 

 corals, and shells, and from the incessant action of the waves, 

 the water becomes charged with calcareous matter, and a portion 

 of this is borne by the waves to the shore, and deposited in the 

 form of calcareous sand, which becomes compact limestone, on 

 the infiltration of crystalized carbonate of lime. A great part of 

 the detritus is thrown down in the depth of the ocean, and there 

 envelopes the remains of vegetables and animals, forming new 

 strata for the investigation of future ages. 



Carbonate of lime is not the only mineral substance held in so- 

 lution by water, but silicious earth, or the basis of flint, which 

 constitutes so large a proportion of the surface of the earth, is found 

 in great abundance in some springs. It is true, that even in 

 the present advanced state of chemical knowledge, we are unac- 

 quainted with any process by which any large proportion of flint 

 can be held in solution bv water. Yet we have unquestionable 

 proofs that in the great laboratory of nature, this is effected on a 

 large scale, as for example in the Geysers of Iceland, and the 

 springs of Carlsbad in Bohemia, and the thermal springs of 

 St. Michael, in the Azores. It seems necessary in order that 

 water should contain any large quantity of silica in solution, that 

 it should be raised to a high temperature, and silicious springs are 

 mostly thermal, and are generally found in volcanic regions. 

 The most celebrated thermal springs are those of Iceland, termed 

 the Geysers. The waters of these boiling springs contain a large 

 amount of silex which is deposited on cooling, upon various sub- 

 stances, similar to the incrustations of carbonate of lime already 

 noticed. The hot springs of Iceland are situated in the south- 

 west section of the island, and more than a hundred of them are 

 found in a circuit of two miles. They rise through a thick cur- 

 rent of lava, which may have flowed from Mt. Hecla, whose sum- 

 mit may be seen at a distance of about thirty miles. It is said 

 j* 



