12 Mr Murchison on the Salt Steppe of Orenburg, 



southern base of a hillock of gypsum at the eastern end of the 

 village connected with the imperial establishment ; and it is 

 one of a series of apparently, for the greater part, natural hol- 

 lows, used by the peasantry for cellars or stores. The cave in 

 question is, however, the only one which possesses the singu- 

 lai* property of being partially fdled with ice in summer, and 

 of being destitute of it in winter. " Standing on the heated 

 ground and under a broiling sun, I shall never forget," says the 

 author, " my astonishment when the woman to whom the 

 cavern belonged unlocked a frail door, and a volume of air so 

 piercingly keen struck the legs and feet, that we were glad to 

 rush into a cold bath in front of us to equalize the effect." 

 Three or four feet within the door, and on a level with the 

 village street, beer and quash were half frozen. A little fur- 

 ther, the narrow chasm opened into a vault fifteen feet high, 

 ten paces long, and from seven to eight wide, which seemed 

 to send off irregular fissures into the body of the hillock. The 

 whole of the roof and sides were hung with solid undripping 

 icicles, and the floor was covered with hard snow, ice, or frozen 

 earth. During the winter all these phenomena disappear, and 

 when the external air is very cold, and all the country is frozen 

 up, the temperature of the cave is such, that the Russians state 

 they could sleep in it without their sheep-skins. 



In order to lay before the Society an explanation of these 

 curious opposite conditions of the cave, the author communi- 

 cated with Sir John Herschel, and received the documents 

 which follow this abstract. With respect to the observations 

 in Sir J. Herschel's letter, Mr Murchison says, he does not 

 conceive that the ice caverns at TenerifFe, in Auvergne and 

 elsewhere, are analogous cases with that at Illetzkaya Zatchita, 

 the frozen materials in the last not arising from the preserva- 

 tion of the snow or ice of the preceding winter, but from the 

 peculiar condition of the cavern during the hottest summer 

 months. He states also, that he particularly urged the au- 

 thorities at Orenburg, as well as the directors of the Salines, 

 to keep accurate registers of the temperature throughout the 

 year, and to ascertain precisely the changes which the cave un- 

 dergoes between the extremes of summer and winter. There 



