330 Artificial Preparation of Medicinal Waters. 
until one was constructed by the ingenious George Clymer*® of Phila- 
delphia, which threw out 400 gallons per minute. The extra cost 
resulting from this unknown obstruction was $4000, and the labor 
required was performed in 7 one days and nights, in the midst 
of an inclement winter.+ 
Art. XII.—On the Artificial Preparation of Cold Medicinal 
Waters; by Wm. Meapr, M. D. ° 
Continued from Page 131. 
Tue observations already made on the early methods of prepar- 
ing cold medicinal waters render it unnecessary to go any farther 
into the subject; it has long been familiar to the scientific chemist, nor 
has its importance ever been doubted by those who know how nearly 
many of the common operations of nature, may be imitated by art. 
A solution of any neutral salt in common water is not sufficient to 
constitute a true mineral or medicinal water; there is scarcely one 
of any value that is not impregnated more or less with carbonic acid 
gas, derived from some natural source. From the investigations of 
Dr. Black, we first learned that in their mild state, the alkalies con- 
tain a gas, by him called fixed air; which gas possesses acid proper- 
ties; that it can be expelled from the mild alkalies, either by heat 
or by the stronger acids, and can then be combined with cald water 
to which it imparts peculiar properties. 
The first attempt to apply this knowledge to medical purposes, 
seems to have been suggested some time after, by Dr. Hulme, who, 
without much chemical experience, proposed to saturate a solution 
of subcarbonate of potash with the gas already named. Being evolv- 
ed by means of dilute sulphuric acid, the water acquired a lively 
pungent and sub-acid taste, and was then found to possess peculiar 
medicinal properties. ‘This preparation which went by this name, 
came into general use for some time in cases of urinary calculi and 
other diseases of the bladder. 
Some time after, lemon juice was substituted for the sulphuric acid, 
and this constitutes what is now called the saline effervescing draught, 
* Inventor of the powerful Columbian printing-press, the first iron press ever 
erected in the United States. 
t See the interesting account by Judge Peters, of the erection of the bridge, attach- 
ed to the first vol. of the Memoirs by the Philadelphia Soc. for promoting agriculture, 
for sale by McCarty and Davis, Philatie!phia. 
