54 SIXTH REPORT — 1836. 



which the natural spring maintains, and access of air during 

 the continuance of the process must be scrupulously prevented. 

 This done, the same fixed ingredients must be presented to the 

 water, and no one principle omitted, however small may be its 

 quantity in nature, or however inert it may in itself be, it being 

 recollected that the introduction of a fresh substance, by the afii- 

 nities it exerts, alters, according to the Berzelian doctrine, the 

 proportions of all the salts previously existing in the water. 

 Nor is this all, for it is necessary that the water should be 

 maintained at the same temperature and under the same pres- 

 sure till the very moment of drinking it. 



Similar precautions must be adopted during the act of bottling, 

 the bottle being previously filled with carbonic acid before the 

 water is passed into it : for if the vessel were already occupied 

 by atmospheric air, much of the carbonic acid existing in the 

 water would be expelled, and, consequentlj', a portion of the 

 earthy or metallic ingredients be thrown down. 



To fabricate, therefore, a successful imitation of a natural 

 spring, a more complicated apparatus is eniploj'^ed than was 

 formerly believed requisite, and the water nnist be made to pass 

 through various successive operations, before the process is 

 wound iqi by the addition of the saline ingredients by which it 

 is mineralized. 



When thus prepared, the factitious water will coincide with 

 the natural one in taste, smell, specific gravity, and other phy- 

 sical properties. The gas-bubbles will rise in the same form, 

 and spontaneous decomposition will take place within the same 

 period and to the same extent. 



The mineral waters prepared by Struve really seem to fulfill 

 these conditions in a great degree, and have stood likewise the 

 test of a rigorous chemical analysis, without the detection of any 

 deviation from the original. 



Their pretensions, indeed, have been occasionally sneered at, 

 as might be expected, by the physicians and chemists, who have 

 taken under their patronage the interests of any one of those 

 naturcil waters, for which the artificial ones are offered as sub- 

 stitutes. 



*' Dr. Struve," says one*, " professed to prepare genuine 

 Carlsbad waters, prior to the analysis of Berzelius, who detected 

 in it six or eight new ingredients. He went on doing the same 

 after the discoveries of this great chemist had been announced. 

 Perhaps ten years hence we shall find half a dozen more princi- 

 ples in the water. But no matter, for we shall always find at 

 Dr. Struve's a supply of the true and genuine Carlsbad water." 



* Fcez, Trait e des Eaux dc Wiesbaden, p. 93. 



