SALT. 



.029 



brine is pimped up till a crust of Mil about three 

 inches thick has been deposited. Wlun the crust has 

 IHTOIIH- hard, it is broken into puces and laid up in 

 heaps in a place protected from rain. A fluid called 

 the bittern, from its containing a number of the earthy 

 bitter salts, drains from these heaps for a long time, and 

 it requires three years exposure to dram them till the 

 salt is esteemed perfectly good. If this draining hag 

 not been completely effected, the salt will deliquesce 

 and have a disagreeable bitter taste. The bittern is in 

 some places collected for the purpo&e of procuring 

 from it sulphate cf magnesia, and other substances 

 containing magnesia. The salt procured by this pro- 

 cess has been called Btii/ Silt, and has always been in 

 great request for preserving animal food. For farther 

 information on the subject, see our article FUANCE, 

 Vol. IX. p. fyl, and INDIA, Vol. XII. p. <H. 



2. By (trti/L iul licat. The preparation of salt by heat 

 is adopted only in countries where fuel can be had at 

 a very moderate price, or where the sun's heat is too 

 weak to effect the evaporation with sufficient rapidity. 



In salt works of this kind, a long and low building 

 called a saltern, is erected near the shore. It is divided 

 into two parts, one called the fore-house for receiving 

 the fuel and covering the workmen ; the other the 

 pan or boiling-house, for receiving the furnace and 

 boiler. There are two openings from the back of the 

 furnaces into the fore-house, and from them is raised 

 a wall to prevent the ashes from flying into the salt 

 pans, and in that wall is a door forming a communi- 

 cation between the two houses. The pans, which are 

 of an oblong form, are comnronly 15 feet long, 12 feet 

 broad, and 15 inches deep. They consist generally of 

 plates of wrought iron united with nails, with a strong 

 cement in the joints. The bottom of the pan is sus- 

 tained by strong iron bars placed across it. The sides 

 of the pan are sometimes made with lead, as iron is 

 -apt to oxidate. Hound the sides of the pan is a walk 

 five or six feet broad, from which the workmen draw 

 out the salt. The roofs of the salterns are fastened with 

 pegs of wood, as iron nails would moulder away in a 

 few months. 



Near to the saltern is a cistern either of wood, brick, 

 or clay, and covered with a shed. This cistern is 

 placed at such a height that the water can run out of 

 it into the pans. Into that cistern the sea water is 

 raised by pumping machinery from a well into which 

 the water is conveyed by a pipe from a pool or lump 

 formed in the sand. 



When the sea water in the cistern has settled and 

 deposited its mud and sand, it flows into the salt pan, 

 beneath which, as soon as it is full, a strong fire is 

 lighted in the furnace. When the water is lukewarm, 

 it is in some places clarified by mixing the white of 

 three or four eggs, with two or three gallons of sea 

 water, and pouring the mixture into the tail pan. The 

 blood of sheep or oxen being sometimes used for the 

 same purpose. 



As the water approaches to the boiling heat, the 

 frothy scum or scratch which appears on its surface is 

 collected into four small pans called scratch pans, one 

 of which is at each corner of the boiler. The water 

 now becomes perfectly clear, and after four hours boil- 

 ing, crystals are seen forming on its surface. The p;m 

 is now filled to the top with fresh sea water from ihe 

 cistern ; the eggs or bullock's blood being used as be- 

 fore, and the black scum removed into the scratch 

 pans which have been previously emptied of their 

 white powder, a sort of calcareous earth which they con- 



VOL. 



PART II. 



taimd. Tim second filling of the pan is boiled down like 

 the firtt, and the pan is filled a third and a fourth time, 

 and boiled in the game manner till tl begin 



t<> shoot. At this period of the fourth boil ng, the fire 

 is allowed to become low, so that the brine only re- 

 mains, in which state it is kept for ten or twelve 

 hour*, while the salt is granulating or filling in grains 

 or small crystals to the bottom of the pan. When the 

 water is nearly drawn off by evaporation, the salt, 

 which is nearly in a dry state at the bottom of the 

 pan, is raked together into one or two heaps till 

 the brine drains from it, when it is conveyed in bar- 

 rows to the st'jre- house. In some fait works the pans 

 are filled up rotn times in place of four, with freh 

 eea water, in which caee the salt is drawn out only 

 once every two days in place of every day, as in the 

 common method. From a pan of 1300 gallons from 

 1 ~> to 20 bushels of salt of 56lbs. each, are obtained 

 every day. In the store-house the salt is laid into 

 drabs or wooden trough?, with shelving bottoms, and 

 a sliding board at the lower end, so as to allow the 

 brine to run off. In three or four daya the salt is ge- 

 nerally quite dry. 



2. Manufacture of Salt from Brine Spring*. 



The method of manufacturing salt from brine springs Manuf 

 difters very little from that of manufacturing it from ture of 

 sea water. 'in our aiticleon CHESHIHE, Vol. VI. p. lC7. f " 

 we have given a brief account of the method and of *** 

 the brine springs in that county; and in our ai ti- 

 de FRANCE, we have described the methods used at 

 Sulins. 



The following account of the American brine springs Brine 

 which we have abridged from Dr. Rensselaer's Essay prJg) 

 on Sa/t, recently published, will be interesting to the An>eric *' 

 reader. 



' Illinois abounds with fait. The most important Illinois, 

 work is near Shawneetown, where there are now seven 

 furnaces in operation to extract salt from the water of 

 three wells, which used to flow on the surface at the 

 rate of sixteen gallons per minute. These works, which 

 have produced 200,000 bushels in a year, at present 

 yield 150,000 bushels, worth about 70 cents on the 

 spot. Two hundred and fifty gallons of brine yield 

 50lbs. of salt. Near one of the wells is a basin-shaped 

 cav.ty of about 400 feet in circumference, the soil in 

 and about which is intimately blended with fragments 

 of earthenware. In the centre of it a well has been 

 sunk, which affords a more concentrated brine, 110 

 gallons yielding 50lbs. of salt. In digging this well, 

 the first fourteen feet were a slight earth, mixed with 

 ashes and fragments of earthenware ; the remaining 

 fourteen were through a bed of clay, deeply coloured 

 with oxide of iron, and containing fragments of pot- 

 tery. The clay has something of the appearance of 

 having been subjected to the action of fire. In a drain, 

 which seems to have answered the purpose of carrying 

 away superabundant water, is a layer of charcoal, six 

 inches deep, and four feet below the surface. The 

 stones in the vicinity seemed as if they had been 

 burnt. 



I should mention that charcoal is found above all 

 the salt mines and brine springs of the Carpathian for- 

 mation. 



Four miles west of this point is another well, 60 ftet 

 deep > in digging, the workmen struck, 



1. A bed of tenacious blue clay, 20 feet thick, at the 

 bottom of which is a small spring of salt water. 



2. A bed of similar clay 25 feet thick, and, 



3x 



