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Selected Articles. 
red, and there is scarcely any disengagement of sulphurous 
acid. 
When the preceding operations have been properly per- 
formed, the oil dissolves without residue in the sulphuric acid; 
if not, a white, transparent oil (impure eupion) will be found 
floating on the acid ; the solution is to be permitted to stand 
for a few hours, or till it is perfectly cold, when it is to be 
mixed with twice its quantity of water. It becomes hot 
and turbid, and a small quantity of oil rises to the surface, 
and is to be removed. The mixture is then to be neutralized 
with ammonia, and left to clear, after having removed any 
portion of oil that may have separated, it is to be distilled in 
a glass retort. At first, water containing ammonia and a 
small quantity of oil will pass over ; these are to be rejected, 
then pure water, and finally, when the residue begins to 
become dry and the temperature is increased, oil passes 
over which was closely united to the ammoniacal salt ; this 
oil is to be again dissolved in an equal volume of sulphuric 
acid, the mixture diluted with water, neutralized with ammo- 
nia and redistilled. The oil which comes over at the close 
of this process is to be washed with a solution of potash, and 
distilled once or twice, till the oil obtains a specific gravity of 
0.98. A small residue of oil mixed with some foreign mat- 
ters will remain in the retort. Finally, the oil is to be di- 
gested with fresh and dry chloride of calcium, which is to be 
several times renewed, and the process terminated by recti- 
fying the product over a spirit lamp. 
Dr. Reichenbach has called this oil capnomor, signifying 
part of smoke. It is a transparent, colourless fluid ; its re- 
fringent power is equal to that of creosote. Its smell is not 
very powerful, but is agreeable and aromatic ; some persons 
compare it to that of ginger, others to that of rum ; its taste 
is at first scarcely perceptible, but in a few moments becomes 
more powerful ; it is neither bitter, acid nor sweet ; it evapo- 
rates rapidly, without leaving a trace, if its specific gravity 
is 0.9775 at a temperature of 20° C. It boils at 185° C; but 
does not congeal at 21° C. It leaves greasy traces on paper 
