434 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



pyrites, while in this country we make it from sulphur. The manufacture 

 of soda ash from salt, in England, is ver}' extensive, but here, owing to the 

 higher price obtained for the salt, very little is made into soda ash. 

 , Prof. Englehardt, of St. Xavier College, said the new method adopted for 

 evaporating the brine is to put it into large kettles, in the centre of which 

 an iron handle is placed, and the sulphate of lime in the brine settles on 

 this iron. When the brine is evaporated, the bromide of calcium, chlo- 

 rid,e of magnesium, &c., adulterate the salt. The manufactory where the 

 salt is made has two rows of kettles, 50 on each side, and these 100 kettles 

 are all heated by the one fire; formerly wood was used but they now buFn 

 coal. Those nearest the fire are evaporated first; when the solution is 

 suflBciently conceiitrated it is removed to a large wooden building and kept 

 there. This salt will always become nujist oii exposure to the atmosphere,' 

 because it contains chlorides of calcium and magnesium, To remove these 

 some thirty or forty bushels of the salt is put into a vat, and to which is 

 added a saturated solution of salt and water; the whole is then stirred up, 

 after which the carbonate of soda is mixed through it, when the chlorine 

 will unite with the sodium of the carbonate and f\)rm chloride of sodium, 

 thus increasing the quantity of salt, while the chlorides of magnesium, &c., 

 called bitterns are converted into carbonates. 



The iron is removed from the salt before it is put into the kettles. The 

 brine is placed into large wooden vats, and allowed to stand for several days; 

 a certain amount of lime is added to it, when tlie lime precipitates the iron. 

 If there is too much lime the chloride of lime will be formed. 



Solar salt is much purer than that made by evaporating by fire. The 

 tanks for solar evaporation are from eight to twelve feet square and six 

 inches deep. They are filled with brine during the winter and allowed to 

 stand covered till Spring, when they are uncovered and evaporation takes 

 place by solar heat. 



Prof. Englehardt illustrated his remarks by a series of formulas on the 

 blackboard, giving in detail the constituents of the salts in their various 

 combinations. • 



The Chairman said it might be interesting to know the comparative 

 strength of the brines found in various parts of the United States. The 

 following table was prepared by the late Dr. Beck of Albany. To make 

 one bushel (56 lbs.) of salt requires 



Of sea water from 300 to 350 gallons. 



Connemaugh, Penn. brine 300 do 



Shawneetown, 111. brine 280 do 



Jackson, 0. brine 213 do 



Lockhart, Miss, brine 180 do 



Zanesville, 95 do 



Grand River, Ark 80 do ' 



Kanawha, Ya , 15 do 



Montezuma, 10 do 



Grand Rapids, Mich s . . . 50 do 



Muskingum, 50 do 



Montezuma, N. Y 50 do 



Onondaga, old wells „ 45 do 



Onondaga, new wells 35 do 



