Rock Salt and Salines of the Holslon. 173 



Art. XVIII. — On the Rock Salt and Salines of the Holston ; 

 by C. B. Hayden. 



The salines of the Holston River, Virginia, are in the shales 

 belonging to the lower portion of the carboniferous series. These 

 salines therefore occupy a medial geological position in relation to 

 the other salines of the United States ; those of Kenawha, and the 

 west generally, being higher up in the carboniferous rocks, and 

 those of New York, according to Messrs. Conrad and Vanuxem,* 

 belong to the Wenlock limestone group of the Silurian System. 

 With the exception of those near Durham, in England, which are 

 in the carboniferous rocks, they are geologically lower than those 

 of Europe. The Holston salinesf are situated in a valley, the 

 bounding hills of which here assume an amphitheatrical arrange- 

 ment, rendering the topography highly favorable by its drainage to 

 the formation of those subterraneous reservoirs of water, which 

 by solution of the saline matter of the adjacent strata furnish the 

 wells with brine, and to this local topography they are indebted 

 for their copious, constant, and uniform supply. This amphithe- 

 atrical valley, to which the discovery of brine has been confined, 

 is about one fourth of a mile in breadth, and a mile in length. 

 The centre of this valley consists of an earthy alluvium with 

 a few interspersed pebbles and small bowlders, forming a flat, 

 through which the salt wells are sunk. This alluvium is gene- 

 rally from eighteen to twenty feet in thickness, and reposes im- 

 mediately upon the gypseous rocks, which are here in an advanced 

 state of decomposition, consisting generally of blue and red clay, 

 derived respectively from the blue and red shales, with which 

 the gypsum is associated. Undecomposed rocks are rarely met 

 with in situ in the wells and borings. The existence of salt 

 springs and licks induced a successful search for salt water very 

 early in the history of the country, but it is understood that the 

 wells were shallow, and the brine both weak and limited in 

 amount, although then sufficient to meet the demand. 



The wells of the present establishments are six in number, 

 but two of which are now in operation. They vary in depth 



* Vide New York State Geological Report for 1840. 

 t Saltville, Washington County, Va. 



