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probability a softened .shale, sucli as that of the brine springs and 

 rock salt of Cheshire in England. In fact, a marked analogy is pre- 

 sented in the structure of the salt region of the Holston, and that of 

 Cheshire. In the latter, beds of gypsum are found alternating with 

 strata of indurated clays and sands, approaching to slates and sand- 

 stones ; and carbonate of lime exists largely in the strata lying near 

 the surface. In all these particulars the salt region of the Holston 

 corresponds with it very closely. 



The great value of the Cheshire region, however, results from the 

 heavy beds of rock salt which it includes, and of the existence of 

 such upon the Holston, though far from improbable, no positive 

 testimony has as yet been obtained. 



The curious fact, that on some occasions granules or small crys- 

 tals of salt, are brought up by the water of the wells, is certainly 

 very much in favour of the opinion, that such beds of the massive 

 salt do actually exist at depths to which the borings hitherto made 

 have not extended, and furnishes strong additional incentives to a 

 persevering and thorough exploration by borings in numerous places 

 penetrating to still greater depths. 



The proportion of common salt varies with different wells, and 

 even in the same is not perfectly uniform. In some cases 10 gal- 

 lons of the brine will yield one gallon of salt, in others 16 are neces- 

 sary. Taking the specific gravity of salt at about 2.5, and allowing 

 something for the interstices in the dry measure, we would have in 

 the former case a strength of about 20 per cent. Gypsum is always 

 present in the brine, and is almost the only impurity in it. 



Of the coal occurring in Montgomery, and other parts of the S. W. 

 region, nothing at present need be added, as the remarks already 

 made in regard to the beds of the same variety of this mineral, oc- 

 curring in the Catawba mountain and elsewhere, would be equally 

 applicable to those found further south. Iron ore of a very peculiar 

 character is found in Grayson and Wythe, &c, yielding in some 

 cases by the usual smelting process, a metal having all the qualities 

 of steel. . . 



The composition of this ore, now not known, would throw great 

 light on this interesting result, and might enable those engaged in 

 the iron works of the country, to secure a uniform production of 

 this more valuable form of metal, instead of being subject to the 



