34 Expedition to the 



lime, potash, &c. occur in great plenty, in connexion with the 

 horizontal limestones and sanJstones on the Ohio. Of 

 these we subjoin some account, from the mineralogical re- 

 port of Mr. Jessup.* 



* J\ Urate of Potash. This salt occurs in most of the caves in the wes- 

 tern states and territories. It is found in efflorescences and incrustations 

 frequently combinded with nitrate of lime. Its colour is grayish or yellow- 

 ish white. The manufacture of nitre, in the numerous caves in Kentucky, 

 is conducted as follows: The earths containing the nitrates of lime and 

 potash are lixiviated ; the lixivium is afterwards passed through the 

 ashes of wood, by the alkali of which the nitrate of lime is decomposed. 

 If the earths, after having been lixiviated, are replaced in the caves, they 

 again become impregnated with the same salts. 



One bushel of earth commonly yields from one to four pounds of nitre. 

 The process by which nature supplies the consumption of this important 

 article has not yet been discovered. 



Muriate of Soda. In the Uuiled States, common salt has been usually 

 found in solution combined with the sulphates of lime, magnesia and soda, 

 and with sulphuretted hydrogen gas. The springs, yielding the greatest 

 quantity of salt, are those of the Kenhawa, and little Sandy rivers, the 

 U. S. Salines near Shawaneetown Illinois, Boon's Saline, near Franklin 

 Missouri, and Lockhart's on the Le Mine river. 



The Kenhawa salt works supply about thirty thousand bushels of salt 

 per annum. The rocks about these springs belong to the secondary for- 

 mation, and are limestone, variegated sandstone and bitumiuous shale : 

 we were informed that two hundred and fifty gallons of this water yield 

 one bushel of salt. At the Salines of the Little Sandy ten thousand bushels 

 are manufactured yearly. The waters, like those of the Kenhawa, hold 

 in solution muriate and sulphate of soda, sulphate of lime, and probably a 

 small portion of sulphate of magnesia. Limestone and sandstone are the 

 only rocks to be met with in the neighborhood. The United States' Sa- 

 lines near Shawaneetown, produce at present about a hundred and thirty 

 thousand bushels of salt per annum ; they formerly yielded more than two 

 hundred thousand in the same time. There are now seven furnaces in 

 operation : the water is procured from three wells, two of which are ren- 

 ted by Maj. I. Taylor. At these works the salt water formerly issued from 

 the earth at the su/face. A well of sixteen feet deep, brought the work- 

 men to a spring, which now discharges sixteen gallons of water per 

 minute. Two hundred and fifty gallons )ield fifty pounds of salt. About 

 one thousand yards to the east of this well is a basin, or hollow, one hun- 

 dred and thirty five feet in diameter. The soil in and about it is intimately 

 blended with fragments of earthen ware. 



In the middle of this basin, a well has been sunk, which affords a more 

 concentrated brine than that before meutioued ; one hundred and ten 

 gallons yielding fifty pounds of salt. * 



In digging this well, the first fourteen feet was through a light earth 

 mixed with ashes and fragments of earthen ware : the remaining fourteen 

 through a bed of clay, deeply coloured with oxide of iron, and containing 

 fragments of pottery. The clay has something the appearance of having 

 been subjected to the action of fire. At the eastern side of the basin ap- 

 pears to have been a drain for the purpose of conveying away the super- 



