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SELECTED ARTICLES. 
These results agree very well with the formula — 
C 42 1607.24 38.61 
H 17 106.08 2.55 
CI 7 1549.27 37.22 
O 9 900.00 21.62 
This would seem to indicate that salicin is, during this re- 
action, deprived of water; and the anhydrous salicin, in its 
turn, loses seven atoms of hydrogen, which is replaced by 
seven atoms of chlorine. 
Jinn, de Chim. et de Phys. 
ART. XX.— ON THE PRESERVATION OF VINEGAR. 
It is well known that vinegar cannot be preserved a long 
time, and that in a few weeks, especially in summer, the surface 
becomes covered with a thick mucus, and the liquid becomes 
cloudy; as this increases, the acidity lessens, and finally disap- 
pears. 
There are at present four modes known by which this altera- 
tion may be prevented. 
The first is to prepare a very acid vinegar ; by this means, 
it is true, it may be preserved many years : but, as persons 
so seldom make their own vinegar, and for the most part pro- 
vide themselves from that found in commerce, this mode 
would be useful only to a few individuals. 
The second process consists in concentrating it by means of 
congelation. A hole being made in the crust of ice and the 
part not congealed placed in bottles. This operation is very 
certain ; but, one-half of the vinegar at least is lost, although 
the crust of ice consists almost entirely of water ; economi- 
cal persons would not willingly use this method. 
The third process is to withdraw the vinegar from all access 
of air, by means of flasks or bottles well corked and always 
