46 On Saltwaters of Alleghany and Keskeminetas Valleys. 



Art. Y.— Observations on the Saltwaters of the Alleghany and 

 Keskeminetas Valleys; by Dr. Edwabd STiEBEiN-. 



Within a distance of about 35 miles above the city of Pitts- 

 burgh there have been bored, on both sides of the Alleghany 

 and Keskeminetas rivers, more than thirty saltwells, the greater 

 part of which are used for the manufacture of common salt. 



These valleys belong to the coal period and the strata have a 

 gentle dip to the southwest. There is no rock-salt, and no de- 

 posits of gypsum have ever been found in this district. 



In boring these wells we pass through sandy shale, fire-clay, 

 limestones, and different kinds of marl and clay-slates, through 

 porous, white and red sandstone in strata of various thickness, 

 and several veins of bituminous coal, from two to seven feet iu 

 thickness. One of these sandstones is from 70 to 100 feet in 

 thickness, and is usually found at a depth of from 200 to 250 feet; 

 this rock contains small quantities of carbonate of lime, baryta 



These mineral waters are, we believe, formed by the percola- 

 tion of meteoric waters through the superincumbent beds of 

 marls and clays, from which, assisted by the carbonic acid 

 received from the atmosphere, and by pressure, they dissolve 

 saline matters till an impenetrable stratum is reached, where they 

 remain, saturating the porous sandstone and filling the fissures 

 of the surrounding beds. 



The wells are from 400 to 1200 feet deep, and from 3 to 3^ 



Keskeminetas valleys during a series of years past has convinced 

 me that, as respects their chemical constituents, they are among 

 the most interesting cold saline mineral waters, which have as 

 yet been analyzed. Several of these wells yield, besides salt 

 water, a very superior quality of petroleum, which has been in- 

 troduced into commerce, and for many years used for medical, 

 illuminating, and lubricating purposes. They also give off an 

 inflammable gas. 



These brines are qualitatively all alike, but not in the quanti- 

 ties of their constituents. Their specific gravities are from 

 1-0175 to 1-098, that is from 2^ to 13 degrees of Beaume's hy- 

 drometer. 



The brines of all the saltworks of both valleys, are without 

 exception pumped by steam power. A yellowish colored sedi- 

 ment, which by degrees becomes red, is deposited in the spouts, 

 in which the brine is carried from the pump to the boiling pan, 



