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having no brine on them, i.e. that the rainfall had never 

 reached, a new method of obtaining brine has been resorted 

 to. A borehole is made to and into the bed of salt, and 

 lined with tubing to prevent the earths falling in. The 

 lower tubes are perforated. Inside this tube is placed 

 another of smaller diameter. Fresh water is poured into 

 the annular space between the tubes and jBnds its way to 

 the salt, which it immediately dissolves, and so becomes 

 saturated brine. This brine rises up the inner tube in the 

 proportion of 10 feet to every 12 feet of fresh water between 

 the tubes. The pumps are put down the inner tube and 

 the brine pumped up for manufacture. This plan is a very 

 modern one, and only carried out in a few districts, though 

 it is being resorted to more largely every day. In parts of 

 Wurtemburg, where the rock salt lies deep and there is 

 no natural brine, the method has been used longest. In 

 describing this plan of getting the salt Quenstedt says, 

 " Klar & Wahr," p. 243 — " Our boreholes are decidedly the 

 cheapest, but they are a species of Robber Mine, where the fresh 

 water at great depths eats away the salt where it can the most 

 easily reach it. Subterranean cavities must originate which 

 will become dangerous." Near Nancy, in France, this sys- 

 tem has been pursued for some time, and at Middlesborough 

 Messrs. Bell Brothers have been extracting salt during the 

 past year in this way from a depth of over 1,200 feet. In 

 April last Mr. T. H. Bell read a paper before the Cleveland 

 Institution of Engineers, describing this method of getting 

 or mining salt. In the discussion which arose one of the 

 most interesting questions was as to the probability of the 

 land sinking owing to the abstraction of the salt by the 

 water. It was stated that at or near Nancy, a sinking had 

 taken place, the shaft collapsing. Now, it is quite certain 



