INTRODUCTION. VJ1 



served, that he had stated the discovery of the metallic nature 

 of the earths and the alkalies, and that the metals obtained 

 from them were in a high degree inflammable when they 

 came in contact with water. Dr. Davy further observed, 

 that previous to the eruption of volcanoes,, the lakes and 

 springs in their neighbourhood were known to have suddenly 

 disappeared ; and all the volcanoes which are in activity are in 

 the neighbourhood of the sea, or of large lakes*. Now if 

 we admit that these earths exist under the surface, in a me- 

 tallic state, the access of water to them would occasion their 

 combustion. The oxygen would be absorbed, and an im- 

 mense volume of hydrogen gas would be produced, which is 

 always found to follow the eruption of flames. This ex- 

 planation of the cause of volcanoes may be considered as a 

 reasonable influence from the discovery of the metallic nature 

 of the earths j and if we admit the operation of electrical 

 agency in the globe, we shall have a cause operating by which 

 the earths may be restored to their metallic form. Thus the 

 process of renovation and decay will be constantly balancing 

 each other, and nature be preserved in a state of eternal 

 youth. The appearance of the Aurora Borealis and the 

 Aurora Australis, render it probable that the poles are in 

 two different states of electricity, and that a constant circu- 

 lation of electric power is taking place. 



" Though new land and soil may thus be formed, Dr. Davy 

 said he was not inclined to admit that the primary and se- 

 condary rocks were thus produced. The crystals they contain 

 are different from those ever found in lava. The experiments 

 of Sir James Hall, which had been thought to establish the 

 volcanic nature of basalfc, he considered as defective. In 

 basalt, hornblende and felspar are distinctly crystallised ; but 

 the fused basalt which had slowly cooled, though it had the 

 form of basaltic prisms, did not contain hornblende or felspar 

 in distinct crystals. 



* The Andes are from 80 to 100 miles distant from the sea, and are only 

 influenced by subterranean lakes. P. 



