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SELECTED ARTICLES. 
culty to the middle of the mass of lime, which we are obliged 
to use. The experiments which I have related do not leave 
room for the belief that the alcohol combines with the hydrate 
of lime, of this I am fully convinced by the following experiment: 
A pound of alcohol of 84°, which contained 0.S00 pound of 
absolute alcohol, was put into an alembic with 500 grammes of 
finely powdered quick-lime, and then distilled by a salt water 
bath; the first portions marked 99.0°; then the degree was ele- 
vated; I obtained absolute alcohol, and finally, towards the 
end of the operation, alcohol of a weaker grade. The water 
in the cucurbit was kept boiling for more than two hours after 
that the alcohol had ceased to come over more than drop by 
drop. All the products collected and united, weighed 94°. 
Their volume was 0.88 of a pound, which contained 0.827 
of absolute alcohol. 
I next employed carbonate of potassa, of which the use is 
recommended by some pharmacopoeias, but of which the 
effects have been imperfectly studied. 
I left, at a temperature of about 15°, 500 grammes of calcined 
carbonate of potassa, to act upon five pounds of alcohol of 86°. 
The carbonate of potassa slowly liquified. The alcohol, which 
at first had dissolved a portion of the alkali, deposited it as 
the rectification advanced. Distilled from the alkaline salt, it 
furnished alcohol of 94°. 
Analogous experiments have afforded me similar results. 
The last experiment was made on 200 pounds of alcohol of 
86°. I obtained nearly the whole of the alcohol of 93.3. The 
last products marked 91°. 
I was desirous of knowing how far the alkaline carbonate 
would carry the rectification. For this purpose, I used 225 
grammes of carbonate of potassa, for a pound of alcohol of 86°. 
I obtained 94.6°. I used 200 grammes of the salt for a pound 
of alcohol already at 946°; after many hours of contact, dis- 
tillation furnished 94.8°; the product returned to the same 
vessel and distilled anew marked 95.4. 
In another experiment, in which I employed 1.500 grammes 
of the salt, and three pounds of alcohol of 93.4°, the product 
