BAILEY. | Mineral Waters. 61 
used in the preservation of food, and they are probably less in- 
jurious than other substances. 
Bromids occur especially in brine, associated with chlorids 
and sometimes iodids. It is evident that the therapeutic value 
is directly connected with the bromin of the associated salt, 
for quite similar effects are obtained whether the positive ele- 
ment be sodium, potassium, or some other metal. The bromids 
are more soluble than the chlorids, and this fact is taken ad- 
vantage of by crystallizing out the salt (NaCl) first, and using 
the mother-liquor for the commercial manufacture of bromin. 
Bromin is very often associated with magnesium in mineral 
waters. | 
These waters are essentially alterative, and are used in the 
treatment of rheumatism, gout, goiter, etc. As they hasten 
retrograde tissue metamorphosis, they are of use in diminishing 
the weight of the body. In cases of poisoning with mercury or 
lead, bromides have been used with success. As sedatives, to 
relieve wakefulness and over brain work, and in cases of epi- 
lepsy, these waters are recommended, and since they promote 
absorption and elimination of used-up material, bromin waters 
can be utilized in the treatment of scrofulous tumors, ulcera- 
tions, and chronic cutaneous diseases. 
Carbonate waters have been discussed under alkaline waters, 
as, so soon as the gas escapes, the waters show an alkaline re- 
action. ‘The gas carbon dioxid itself, however, when dissolved 
in water, is agreeable to the taste, and very often grateful to 
the stomach. The very extensive use of artificial carbonated 
beverages, ‘‘soda-water,’’ sweetened and flavored, it is true, 
shows the favor in which a solution of this gas is held. Except 
in a general way, little is known in regard to the action of car- 
bon-dioxid gas, for in most waters it is assumed to be present to 
form alkaline carbonates. The activity of carbon dioxid is not 
destroyed by neutralization, as is the case with other acids. 
‘‘When absorbed it is fixed in the form of sodium bicarbonate, 
which is dissociated so readily that it acts both as an acid and 
an alkali. It has a somewhat specific effect in diminishing 
vomiting. On account of the stimulation of the sensory nerves 
