ADULTERATION OP 
ESSENTIAL 
OIL. 
249 
ART. LII.— MODE OF DETECTING THE ADULTERATION OF 
ESSENTIAL OIL WITH ALCOHOL, BY MEANS OF CHLO- 
RIDE OF CALCIUM. By M. Borsarelli. 
The author provides himself with a small cylindrical tube 
about three centimetres in diameter, and twelve in length, 
closed at one extremity. He fills this two-thirds full of the 
essential oil, and introduces small pieces of chloride of cal- 
cium, perfectly dry, and totally free from dust ; the opening 
of the tube is then closed, and heat applied for four or five mi- 
nutes, by means of a salt water bath, of the temperature of 100°, 
taking care to shake the mixture occasionally, and then allow- 
ing it to cool slowly. 
If the essential oil contains a notable proportion of alcohol, 
the chloride dissolves entirely, and forms a stratum of liquid 
which occupies the inferior portion of the tube, while the es- 
sential oil rises above. When the essential oil contains but a 
very small proportion of alcohol, the pieces of chloride of cal- 
cium, lose their form and reunite at the bottom into a white 
adherent mass. Finally, when the oil is perfectly pure, the 
fragments of chloride do not undergo any change even in 
shape. 
It is proper to add, that when we wish to test any essential 
oil, we should employ the chloride of calcium, in very feeble 
quantities at first, and afterwards to add gradually the new frac- 
tions, lest if the proportion of alcohol be very small, it should 
not be absorbed by the chloride without sensibly changing it, 
or without its presence being recognised. In every case it is 
easy to determine the proportions of a mixture of alcohol and 
essential oil, by comparing its volume or weight with the vo- 
lume or weight of the essential oil which floats upon the surface 
of the alcoholic solution of the chloride, when the operation is 
finished. 
The author adds, that the same process may be employed 
to detect the quantity of alcohol which ether may contain, by 
using a longer tube and taking care not to close it very exactty. 
Rev. Scien. et Indust. and Joum. de Pharm. 
VOL. VI. — NO. III. 32 
