90 HOT SPRINGS, ARKANSAS. 



forming- Hot Springs Mountain. This line is believed to be a fissure 

 corresponding to a fracture of the northwest fold, a fault fissure. 

 Springs are common along such fractures in the novaculite region of 

 Arkansas, and there is no reason to believe there is anything unusual 

 in this one. The source of heat is discussed elsewhere. 



THE HOT SPRING WATERS. 



The Hot Springs yield waters of remarkable purity. This, in fact, is 

 the reason ascribed by some physicians for the efficacy of the water 

 as a remedial agent. The very complete analyses given in this report 

 show a very small amount of mineral matter. The purity of the natu- 

 ral waters of the region is well known. The water of the Happj^ Hol- 

 low spring has less mineral matter than any other of the waters known, 

 except that of the Poland spring, of Maine. These waters rise through 

 siliceous rocks, and the fact that the hot waters contain so little mineral 

 matter, particularly silica, is evidence of their meteoric origin, and 

 accords with the nature of the gases given off by the springs. 



A direct comparison of the analyses with those made in earlier years 

 is not possible, since the analyses are given in parts per million, while 

 those of the State geological survey are in grains per gallon. I have 

 recalculated the analyses of the larger springs, however, and find the 

 analyses nearly identical, showing conclusively that the nature of the 

 waters is not changing with time. 



The accompanying table gives a recapitulation of the analyses made 

 by Mr. J. K. Haywood, of the Bureau of Chemistry, Department of 

 Agriculture. 



