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SELECTED ARTICLES. 
ing or ripening them, more especially by the method employ- 
ed in the case of sherry, madeira, and such other wines, which 
consists of slow evaporation, for a series of years, through the 
cask, above, all in hot climates. The researches made by the 
author on this head are not complete; but he is inclined to 
infer from the experiments already made, that, for a moderate 
term of years, the proportion of alcohol increases in wine, but 
afterwards, on the contrary, diminishes; and that the period 
when the wine begins to lose its alcoholic strength is probably 
that at which it ceases to improve in flavor. The increase 
which takes place at first in the alcohol of wine undergoing 
evaporation through the cask, appeared at first view parallel 
to the fact generally admitted on the authority of Soemering, 
that spirit becomes stronger when confined in a bladder, or 
in a vessel covered with a bladder, in consequence of the 
water passing out by elective exosmose. 
The author, however, on repeating the experiments of Soe- 
mering, as related by various writers, (for he could not obtain 
access to the original account of them,) was unable, by any 
variation of the process he could devise, to obtain the results 
indicated by the German anatomist. Constantly the spirit, 
whatsoever its strength, whether proof spirit or rectified spirit, 
became weaker. It was observed at the same time, that if 
the bladder containing spirit was enclosed in a confined space 
containing quick-lime, the spirit slowly became absolute al- 
cohol of the density of 796, in consequence of a permanent 
atmosphere of alcohol being speedily formed, while the wa- 
tery atmosphere was absorbed by the quick-lime as fast as it 
was produced. Subsequently it was proved that the bladder 
was not essential to the process; for an open cup of rectified 
spirit enclosed in a confined space with quick-lime, to absorb 
the water which arose from the spirit, became in two months 
absolute alcohol, of the density of 796. Professor Graham, 
of London, some time ago proved the analogous fact, that spirit 
might be thus rendered pure alcohol in the vacuum of an air 
pump. A vacuum, however, is, upon principle as well as 
fact, not necessary to the process; it merely accelerates it. 
