152 NEW EVAPORATING HOUSE FOR SALT WORKS. 



2*ew method the process is saved. When the solution is brought to the 

 the ?alt with- g P°^ nt °^ saturat i°n, it is conveyed to a reservoir, whence it 

 out fire, is raised by a chain-pump to a trough at the top of a wooden 



building, and extended its whole length. From this trough 

 it runs into a series of very narrow troughs at right angles 

 to it, and about two yards long, To each of these are 

 twenty-five double or endless roves, 6 millim. [2*4 lines] 

 in diameter, 13 cent. [5 inches] from each other, and fixed 

 8 met. [26 feet] below. The saline water, flowing con- 

 stantly out at notches cut in the sides of the troughs, 

 trickle- down the ropes, round which it forms a very thin 

 coat, displaying a considerable surface to the solvent power 

 of the air. As the water evaporates, the salt is deposited on 

 the ropes. The water that flows down runs into the reser- 

 voir, and is pumped up again repeatedly, till it is exhausted, 

 when it is suffered to run into the basin, that contains the 

 mother- water. 



The water of a fresh boiling is treated in the same man- 

 ner, and thus seventeen boilings are raised in succession, 

 forming one making, which occupies forty or five and forty- 

 days. At the expiration of this time the ropes are covered 

 with a cylindrical coat of bait 7 or 8 cent. [2*75 or 3*15 in- 

 ches] diameter, which is broken by a particular instrument 

 for the purpose. As this process can be executed only in 

 summer, seldom more than two making stake place in a year. 

 Every boiling, before it reaches this building deposits 100 

 myriagr. [2205 lbs] of salt in the boilers; and 650 myr. 

 [14332 lbs.] are collected from the ropes, making in all 750 

 myr. [16537 lbs.] This process therefore does not yield 

 quite so much salt, as the product of the evaporation of a 

 similar quantity of water by two boilings would be 786 myr, 

 [17332 lbs.] ; but then there is a considerable saving of time 

 and labour, as well as of fuel, and the salt obtained is more 

 pure. 



This process, equally ingenious and economical, invented 

 by Mr. Dubutet, has been employed with success ever since 

 the year 1788. It has not yet been adopted in any other 

 salt works. It would be particularly advantageous in hot and 

 dry climates. 

 It may be used Mr. Roche has enhanced the ulility of this building, by- 

 employing 



Quantity of 

 fcalt made. 



The process 

 has been fol- 

 lowed 20 years. 



