ACTION OF VOLATILE OILS ON THE SULPHATES. 303 
every case it is brought upon a filter, washed, dried, and 
the iodine extracted by one of the known processes. Cal- 
cining the protiodide of copper, previously mixed with 2 
equivs. of peroxide of manganese, may be successfully em- 
ployed. The reaction above described is so readily pro- 
duced, that we have no doubt that in future all ioduretted 
waters, even the weakest, will be treated by this process ; 
and that it will likewise be successfully employed for the 
analysis of mineral waters containing bromine and iodine. 
Cfiem. Gaz. from Jour, de Pharm. 
ART. LXXXI. — ON THE ACTION OF VOLATILE OILS ON THE 
SULPHATES IN AN AQUEOUS MENSTRUUM. 
By Mr. William Bastick. 
In making some experiments in reference to the best 
method of preserving the aromatic distilled waters of the 
Pharmacopoeia, I was induced to try the results arising 
from a mixture of volatile oils with water, obtained from a 
spring, containing a considerable quantity of sulphate of 
lime, and other salts in solution, but no organic matter, 
and having neither acid nor alkaline reaction. 
The various oils were mixed with different portions of 
water, and kept in bottles in a moderately warm place for 
about two months. At the end of that time the waters 
were examined, and found to be saturated with sulphuretted 
hydrogen, the presence of which was readily ascertained 
by the smell, and by precipitation of the metallic bases 
usually adopted for that purpose. 
On removing the sulphuretted hydrogen by precipitation 
with a metallic salt, the whole of the volatile oils were 
found to have disappeared; no trace of them could be dis- 
covered by the taste or smell ; and on examining the waters 
