BAILEY. | Mineral Waters. 53 
tion of calculi. In gout, as the excessive acid condition of the 
blood is modified, the uric acid is more readily eliminated. 
Excessive acidity in the alimentary canal, which leads to 
gastro-intestinal catarrh, is benefited by the use of alkalies. 
If this acidity is in the stomach it may be neutralized by the 
use of waters containing sodium bicarbonate; if in the intes- 
tine, and cathartic action is not desired, calcium bicarbonate or 
calcium phosphate can be employed. 
THERAPEUTIC ACTION OF INDIVIDUAL ELEMENTS. 
A.—Base-forming Elements. 
Aluminum is not often present in large quantity in waters 
that are used for drinking, but, as previously noticed, it is a 
common constituent of acid waters, like some of the alum springs 
of Virginia. Comparatively little can be said of the action of 
the aluminum ion, but the alums are used locally as astrin- 
gents, and internally in gastric catarrh, enteralgia, gastralgia, 
lead colic, etc. 
Ammonium is not present in large enough quantities to pro- 
duce any decided effect, as far as known. In fact, since it is 
produced by the decomposition of organic matter, sanitary 
chemists are disposed to look upon it with suspicion, as in- 
dicative of contamination of the water. This is not necessarily 
the case, however, because some waters have been found con- 
taining ammonium saltsasanatural constituent. From astudy 
of the ammonium ion, it is evident that it has a marked action 
on the secretions, especially saliva, mucus, and sweat. It is 
used as a local expectorant, and asa stimulant of the respiratory  - 
centers, for cough and asthma. 
Barium, in its ion actions, resembles the organic groups. Its 
most important systemic action is a slowing of the heart and 
-a rise in blood pressure. It is said that when barium is given 
in very dilute solutions the amount absorbed is very small, 
and is deposited in the bones. It may be of use also in the 
treatment of cancerous, scrofulous and other morbid growths. | 
Calctwm compounds are very abundant in mineral waters. 
The carbonates are very alkaline in action, and in large doses 
