220 JVotes on Maiural Histcr-j, ^x. [April, 



temperature of these hi 2;h southern regions. In many places, the 

 energetic influences of this powerful agent were peculiarly strik- 

 ing, extensive masses of the rocks had been completely converted 

 into huge disintegrated heaps of ruin, contributing in no small 

 degree to the dreary and desolate effect, which everywhere pre- 

 sented itself to the si<2;ht. The average time of the fall of these 

 fragments may be computed at about once in every ten minutes, 

 so that its destroying energy at this place, may be duly appre- 

 ciated. 



" Not only does sulphur thus occur among rocks, but it is also 

 disseminated throughout the ocean, sulphate of soda being one of 

 the salts constantly present in all analyses of sea water. M. Eich- 

 wald states that sulphate of magnesia is a common salt in the 

 waters of the Caspian sea." — De la Beche. 



While at Bonavista, one of the Cape de Verde Islands, where 

 salt is extensively manufactured by solar evaporation from the sea, 

 I made an excursion to the works. Their method is, during gales 

 of wind and high tides to admit water from the sea to float over 

 depressed plains, or basins, where for a time it is exposed to the 

 influence of a tropical sun; after a deposition of the salt, the su- 

 perfluous water is drawn off into pits prepared for its reception. 

 In these pits, and in the vicinity of these salt-pans, large masses 

 of beautiful transparent crystals of sulphate of lime are formed, 

 embracing not only fragments of the trap which form the hills 

 and rocky portions of the island, but likewise, in some abundance, 

 the recent species of shells which inhabit the neighboring sea. 



De la Beche considers it very doubtful if-a shark could continue 

 long to exist beneath considerable depths. This, in a great mea- 

 sure, may be true, but circumstances sometimes occur, which 

 would induce us to believe them capable of a much longer dura- 

 tion in this situation than has been generally imagined. 



