In the lime stone country are many caves, the earthy floors of which are impregnated with nitre. On Rich Creek, a branch of the Great Kanhaway, about 60 miles below the lead mines, is a very large one, about 20 yards wide, and entering a hill a quarter or half a mile. The vault is of rock, from 9 to 15 or 20 feet above the floor. A Mr. Lynch, who gives me this account, undertook to extract the nitre. Besides a coat of the salt which had formed on the vault and floor, he found the earth highly impregnated to the depth of seven feet in some places, and generally of three, every bushel yielding on an average three pounds of nitre. Mr. Lynch having made about 1,000 ℔ of the salt from it, consigned it to some others, who have since made 10,000 ℔. They have done this by pursuing the cave into the hill, never trying a second time the earth they have once exhausted, to see how far or soon it receives another impregnation. At least fifty of these caves are worked on the Greenbriar, There are many of them known on Cumberland River.
The country westward of the Alleghaney abounds with springs of common salt. The most remarkable we have heard of are at Bullet's Lick, the Big Bones, the Blue Licks, and on the North Fork of Holston. The area of Bullet's Lick is of many acres. Digging the earth to the depth of three feet, the water begins to boil up, and the deeper you go, and the dryer the weather, the stronger is the brine. A thousand gallons of water yield from a bushel to a bushel and a half of salt, which is about 80 ℔ of water to 1 ℔ of salt; but of sea water 25 ℔ yield 1 ℔ of salt. So that sea water is more than three times as strong as that of these springs. A Salt Spring has been lately discovered at the Turkey Foot on Yohogany, by which river it is overflowed, except at very low water. Its merit is not yet known. Duning's Lick is also as yet untried, but it is supposed to be the best on this side the Ohio. The Salt Springs on the margin of the Onondago Lake are said to give a saline taste to the waters of the lake.
There are several Medicinal Springs, some of which are indubitably efficacious, while others seem to owe their reputation
