weather. The most important of these are the rock salt 

 mountain of Cardona, in Spain, the Kohat rock salt in 

 North-west India, the Great Salt Range at Kalabagh, Usdum, 

 at the south of the Dead Sea, and in Transylvania numerous 

 beds exposed in the valleys of rivers and brooks in the 

 Carpathian mountains. In England all the beds of rock salt 

 lie at a considerable depth below the surface. In sinking 

 down to these beds, water-bearing strata are almost in- 

 variably met with, and when the shaft, passing through 

 the rock salt to the mine either in the lower portion of the 

 first salt bed or in the second bed, is not made perfectly 

 watertight, so as to prevent the upper waters reaching the 

 salt, the same action takes place as in the salt beds exposed 

 to the rains and moisture of the atmosphere. 



In Kohat there is on an average a solution of two inches 

 of rock salt on the exposed surface annually. In the wet 

 season the rains channel and furrow the surface of the salt 

 bed and then run off in tiny streams of a saline nature to 

 the brooks and rivulets. The clay, always existing in rock 

 salt, prevents some portions from being eaten away, and 

 the salt presents not one even smooth surface as might be 

 supposed, but a channeled and columned or fluted surface 

 in parts, with here and there marly protuberances or ledges. 

 In Transylvania the solution of the salt by water percolating 

 through the thin layer of earth which in many parts covers 

 it causes landslips which leave the face of the rock salt 

 exposed. The quantity of salt dissolved by rain in these 

 exposed salt beds is not nearly so much as might be ex- 

 pected, for the rain runs down the face of the rock too 

 quickly to become saturated. At Cardona we are told that 

 the mountain loses only four feet in 100 years, or about 

 half an inch per annum. The eating or destroying force of 

 fresh water when directed continuously over a salt bed has 

 been taken advantage of at Varangeville, near Nancy, in 

 mining rock salt. A fine stream of fresh water is turned 



