and on a remarkable Freezing Cavern. 11 



masses attracted the attention of the Kirghiss long before the 

 country was colonized by the Russians ; but it is only during 

 a short period that the great subjacent bed has been exten- 

 sively worked. The principal quarries, exposed to open day, 

 are situated immediately south of the establishment, and have 

 a length of 300 paces, with a breadth of 200, and a depth of 

 40 feet. The mass of salt thus exposed is of great purity, 

 the only extraneous ingredient being gypsum, distantly dis- 

 tributed in minute filaments. At first sight the salt seems to 

 be horizontally stratified, but this apparent structure, Mr Mur- 

 chison states, is owing to the mineral being extracted in large 

 parallelopipedal blocks 12 feet long, 3 feet deep, and 3 wide. 

 On the side where the quarry was first worked, the cuttings 

 presented, in consequence of the action of the weather, a ver- 

 tical face as smooth as glass, but at its base there was a black 

 cavern formed by the water which accumulates at certain 

 periods of the year, and from its roof were saline stalactites. 

 The entire range of this bed of salt is not known ; but the 

 mass has been ascertained to extend two versts in one direc- 

 tion, and Mr Murchison is of opinion that it constitutes the 

 subsoil of a very large area ; its entire thickness also does not 

 appear to have been determined, but it is stated to exceed 100 

 feet. The upper surface of the deposit is very irregular, pe- 

 netrating, in some places, as already mentioned, the overlying 

 sands and marls. 



In consequence of the salt occurring at so small a depth, 

 every pool supplied with springs from below is affected by it ;* 

 and one of them used by the inhabitants as a bath, is so highly 

 charged with saline contents, that there is a difficulty in keep- 

 ing the body submerged, and the skin, on leaving the pool, is 

 encrusted with salt. This brine swarms with animalcules. 



II. Mr Murchison then describes the freezing cavern and 

 the phenomena exhibited by it. The cave is situated at the 



* The abundance of these brine springs in various parts of Russia must 

 lead, the author says, to the abandonment of Pallas's hypothesis, that the 

 saline pools and lakes are the residue of former Caspians ; though he admits, 

 that some of the vast low steppes of the south formed the bottom of a former 

 condition of the existing Caspian. 



