UKW EVAPORATING HOUSE FOR. SALT WORKS, |£ J 



" The potassium is never procured quite so pure in this Near 100 

 manner, as by electricity; but it is lit for analytical pur- ^ass Procured 

 poses, and I have obtained it with so little alloy, as to pos- by one opera- f 

 sess a specific gravity considerably below 8, water being 10. tlon ' 

 I have now by me a compact mass produced in an operation 

 which weighs nearly 100 grains." 



XI. 



Account of an economical Method of Evaporating the Water 

 of Brinesprings, employed at the Salt Works of MoHtiers, 

 in the Department of Mont-Blanc. By Mr. H. Lelivec, 

 Engineer of Mines, Sfc. for the Departments of Mont-Blanc 

 and the Leman Lake*. 



JL HE richest spring at Moutiers is constantly at the tem- Brinesprings at 



perature of 30° R. [99*5° F.], and when cooled dowu to 10° Moutiers. 



[54*5°] indicates on the areometer r83°f. The poorest raises 



the thermometer to 25° [88° F.] only, and indicates \'5° of 



saltness. The water is conveyed by troughs to a large re- Method of 



servoir, where it is left to settle ; and thence it passes through P rocurir ff the 



, , i • , i ii salt from them, 



other troughs to graduation nouses about 1100 yards, lower 



down. In its course it gives out bubbles of carbonic acid 

 gas, and deposits a reddish sediment, which is at first oxide 

 of iron, then a mixture of this with carbonate of lime, and 

 at length almost wholly calcareous carbonate. It passes 

 through four graduation houses in succession, and comes out 

 of the last at the strength of 18°, and sometimes more. It 

 is then boiled for about six and twenty hours, or till the salt 

 begins to crystallize, keeping ti.e boilers constantly full; a 

 foulness, that rises, is scummed off; and the sulphate of 

 lime it contains is precipitated. 



The sulphate of lime being raked out, in winter the eva- 

 poration is continued, with a slow fire, till the whole of the 

 salt is deposited : but in summer a different process is foU 

 lowed, by which all the fuel consumed in the last stage of 



* Journal des Mines, No. 120. 



•f The areometer commonly employed in the French salt works is di- ' 

 vided into 50 degrevs, beginning at distilled water, and ending at water ' 

 saturated frith salt. 



the 



