M. Eichwald's Remarks on the Caspian Sea. 825 



at its eastern extremity, in very numerous lakes, which, like 

 those at Baku, are very productive of salt. It is deposited 

 in the bottom in masses sometimes a foot thick, which are 

 transparent or muddy, and consists of closely aggregated crys- 

 tals. It is dug as at Baku ; masses generally an ell in length 

 and one foot thick are hewn, and in this form sent into Persia. 

 Its colour is white ; sometimes it has a bitter taste, and occasions 

 diarrhoea, a proof of its containing glauber and epsom salt. 

 Some of these salt-lakes are several thousand feet in circum- 

 ference ; and in some of them the water is so warm, so hot in- 

 deed, that we cannot keep our hand in it. The beds of salt 

 which are deposited from the water, resemble rock-salt. As 

 the salt is generally pure muriate of soda being seldom mixed 

 with foreign matter, it crystallises more readily than the salts 

 from sea- water. The many naphtha wells, as also the hot wa- 

 ter of the springs on the island, show that its salt, like rock- 

 salt, owes its origin to a volcanic heating process. Hence, we 

 find every where on the Continent, where salt-mines occur, vol- 

 canic productions as proofs of a former igneous process. Thus 

 there is a small range of hills some miles from Wieliczka, 

 in which we find at the same time sulphur and pumice, and 

 springs of sulphureted hydrogen gas. At Burgos in Spain, a 

 bed of rock-salt has been formed in the crater of an extinct 

 volcano ; we find in it pumice, puzzolano, and other volcanic 

 products, which are intermixed with the salt. At Baku, and in 

 the Island of Tschelekaen, we observe, as volcanic phenomena, 

 very distinctly heatings of the interior of the earth. This salt 

 can only be distinguished from rock-salt, in this respect, that 

 the latter originates at once from a pretty widely extended 

 volcanic eruption, and forms at the same time beds extending 

 for miles, which are consequently proofs of former igneous 

 action. But the salt of the Caspian is formed in a different 

 manner, through long still continuing heating of the interior of 

 the earth, which decomposes the salt water. 



The Bay of Balchan. — At Krasnowodsk, on the north coast 

 of the Bay of Balchan, all the projecting points of land are 

 composed of coarse granular granite ; and a little into the 

 anterior, there rises a steep and rough porphyry mountain. 

 This granite, and various porphyries along with a compact lime- 



