318 ASHLEY GEOLOGY OF ARKANSAS. [May 13, 



'' Sulphuret of sodium. 



^' Traces of sulphate of soda. 



*' Traces of sulphate of magnesia. 



"Its medical properties will be found to be analogous to those 

 of Baker's Spring. 



"Nathan Aldridge's Sulphur Spring contains the same constitu- 

 ents, only differing slightly in the proportions." 



As shown in PI. ii, these springs all rise from the same layer of 

 shale. 



The principal constituents of the Gap Springs are given by 

 Owen as : 



" Chloride of sodium. 



" Sulphate of soda. 



" Sulphate of magnesia. 



" Bicarbonate of alkali. 



"And probably a little sulphuret of alkali. 



" A trace of carbonate of lime." 



An examination of the so-called alum spring gave indications 

 of the same ingredients, with the exception of the absence of sul- 

 phur, the presence of iron and a larger proportion of sulphates. 

 These waters will have a mild, aperient effect, combined with a 

 slight alterative action on the system." 



Tyra springs in 5 S., 32 W., section 2, consist of a number of 

 springs on the north bank of a small tributary of the Rolling Fork 

 of Little river just west of Hatton Gap. The south bank and bed 

 of the stream are novaculite, so that they appear to come from a 

 layer of shale immediately overlying the novaculite. 



Bog Springs are located in the pass of Cross creek through South 

 or Bog mountain on the west side of the creek. They flow out 

 from the foot of the mountain only a few yards from the creek. 

 The principal spring forms a considerable bog. 



As a rule, this area of Carboniferous rocks is well supplied with 

 springs, and the streams are remarkably clear and the waters soft. 



