10 MINERAL WATEBS OF THE UNITED STATES. 



as the foregoing would produce a sliding scale, and would classify as 

 thermal a water which in a warmer climate would be nonthermal, it 

 has been thought best to adopt the scheme of Dr. A. C. Peale, and 

 classify all waters above 70 F. as thermal and all below as nonthermal. 

 Waters between TO F. and 98.6 F. would, according to this classifi- 

 cation, be considered as tepid or warm, while waters above 98.6 F. 

 would be considered as hot. 



Alkaline waters are (1) those which have an alkaline reaction a and 

 contain carbonic or bicarbonic acid ions in predominating quantities; 

 (2) those which have an alkaline reaction and contain boric or silicic 

 acid ions in predominating quantities, where it can be proved that the 

 alkalinity is largely due to the presence of borates or silicates. The 

 first class of alkaline waters is well known and is given in Peale's 

 classification as constituting the w r hole class of alkaline waters. The 

 second class of alkaline waters includes those which are more alkaline 

 than can be accounted for by the carbonates or bicarbonates present, 

 and contains predominating quantities of silicates or borates, which evi- 

 dently cause this excess of alkalinit} 7 . 



Saline waters are those which have an alkaline or neutral reaction 

 and contain sulphuric, muriatic, or nitric acid ions in predominating 

 quantities. 



Alkaline-saline waters are between alkaline and saline. They em- 

 brace those which have an alkaline reaction and contain (1) sulphuric, 

 muriatic, or nitric acid ions along with carbonic or bicarbonic acid ions, 

 both classes being present as predominating constituents or those which 

 have an alkaline reaction and (2) contain sulphuric, muriatic, or nitric 

 acid ions along with boric or silicic acid ions, both classes being present 

 as predominating constituents, where it can be proved that the. alka- 

 linity is largely due to the presence of borates or silicates. 



Acid waters are those which have an acid reaction, and contain either 

 sulphuric or muriatic acid ions in predominating quantities. 



METHOD OF NAMING MINERAL WATERS. 



If any basic element is prominent in the mineral water this fact 

 may be indicated by prefixing the name of the base to the regular 

 class name; as sodic, lithic, calcic, etc.; carbonated alkaline, borated 

 alkaline, silicated alkaline, sulphated alkaline-saline, etc. 



If any basic or acid ion is prominent therapeutically but not chemi- 

 cally, this fact may be indicated by affixing the name of the basic or 

 acid ion to the regular name; as carbonated alkaline (arsenic, bromic, 

 iodic, etc.). 



a Where acid and alkaline reactions are mentioned in these definitions, methyl 

 orange is supposed to be used as indicator. 



