MANUFACTURE OF SALT. 113 



Professor W. B. Rogers thinks that some of the brine wells on the Holston, in Virginia, 

 contain about twenty per cent, of saline matter ; which, if the impurities are not in larger 

 proportions than usual, must be stronger than any yet found in this country. 



With the above exception, however, the Onondaga brines are the strongest of all the Ame- 

 rican varieties. But there are still some considerations which should be taken into the account 

 in estimating the relative value of these brines. Thus the Kenhawa brine is said not to con- 

 tain any sulphate of lime, and hence the process of obtaining the salt in a pure crystalline 

 form is attended with fewer difficulties than usual. Another great advantage possessed at 

 these salines is, that coal may be obtained at comparatively little cost from the hills adjacent 

 to the salt furnaces ; and their importance may be judged of by the fact that about 3,000,000 

 of bushels of salt are now annually made from them.* 



The facts just stated are worthy of the attentive consideration of those who are interested 

 in the Onondaga salines. As it is not probable that coal will be found in their vicinity, and as 

 wood for fuel must gradually increase in price on account of the wanton destruction of our 

 forests, every suggestion for economizing its consumption is deserving of careful examination. 



It is evident, that in proportion as the strength of the brine increases, the quantity of fuel 

 required for the manufacture of salt will be proportionably diminished. A brine containing 

 twenty-six per cent, of saline matter, like that of Nortwich in England, would of course require 

 less fuel for its conversion into salt, than one which contains only one half of that quantity. 

 It is on this account that the borings recently executed, as they have opened sources of much 

 stronger brine than were previously known, become of great importance ; and the attempts to 

 obtain still more highly charged waters should be constantly renewed. 



Many expedients are resorted to for the general purpose of economizing the fuel, some of 

 which deserve the attention of those who have the oversight of this important manufacture. 

 Among these may be mentioned the partial evaporation of the raw brine, by causing it to fall 

 in small streams, through faggots of wood arranged across each other, or through a collection 

 of ropes stretched perpendicularly. By these arrangements the brine is divided, and present- 

 ing a larger surface, evaporation is facilitated, and the brine collected in the vessels below is 

 much stronger than that which was pumped up. This contrivance is extensively adopted in 

 Lombardy, Saxony, Bavaria and France. t To show the advantage which may be gained in 

 this way, it may be stated that sea water has its density increased from 1 .010 to about 1 . 140. 

 Such an increase of strength would be sufficient to bring the Salina brine nearly to the point 

 of saturation. 



Some steps have already been taken in reference to this subject. In 1839, the Legislature 

 appropriated the sum of $15,000 for the purpose of erecting reservoirs, in which the concen- 

 tration of the brine and the precipitation of the usual impurities should be effected, under the 

 direction of the agents of the State. Ten reservoirs were erected, of one hundred feet in 



* W. B. Rogers. Report of the Geological Reconnoiaance of Virginia. 1836. 



t For a particular description of apparatus, see Dhmas, Chimie appliquee aitx Arts. Mr. Mather has made a similar 8ugg;e8tion 

 for the concentration of ^^ . water on our coast. New-York Geological Reports^ 1837. 



Part I. 15 



