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seem that much of the water must reach the salt bed 

 at what may be called its subterranean outcrop, or the 

 edges of the salt. No sooner does water reach the 

 salt bed than it proceeds to dissolve the salt, and as 

 the various brine pumping centres keep up a constant 

 and rather rapid motion in the brine, all the particles 

 of water come into contact with the salt or become 

 diffused with the particles that have been in contact, so 

 that by the time the water approaches the pumping centres 

 it has become fully saturated, and ceases to cause any fur- 

 ther solution of salt. The constant removal of the saturated 

 brine and its replacement by what was fresli water at the 

 commencement causes a destruction of the surface of the 

 salt, and consequently a lowering of the whole bed of salt. 

 This lowering does not occur equally over the whole surface, 

 but the streams run in channels which they have dissolved 

 out for themselves, exactly as the rains draining off the sur- 

 face of the land form rivulets, brooks, &c. These channels 

 gradually get wider and deeper. The overlying earths fol- 

 low the decreasing salt bed, and the surface of the ground 

 conforms to the surface of the salt. Thus we have all over 

 the salt district hollows or synclinals. These sinking por- 

 tions develop most rapidly in the neighbourhood of streams, 

 for the flexure of the marls and earths, in following the 

 wasting salt surface, causes cracks and rifts, down which the 

 fresh water finds its way and accelerates the action going 

 on below. In time the land sinks below the level of the 

 river, and the fields immediately adjacent become covered 

 with water, and large lakes form, like the Upper and Lower 

 Flashes at Winsford, and the Top of the Brook at North- 

 wich, which cover more than 200 acres of land, and have 

 formed within the last 60 years. In places where there are 



