304 ACTION OF VOLATILE OILS ON THE SULPHATES. 
for sulphuric acid, by means of muriate of barytes, no 
precipitate could be obtained but what was soluble in 
nitric acid, clearly showing the entire decomposition of the 
sulphates in the original water. After boiling the waters to 
free them from sulphuretted hydrogen, they were found to 
possess an alkaline reaction, and to evolve carbonic acid on 
the addition of an acid. 
The waters had not become mucilaginous, as is usually 
the case when decomposed, but to the eye preserved the 
same appearance as when first prepared. 
In fact, the metamorphoses appear to have been brought 
about by the mutual reaction of the elements of the sul- 
phuric acid, of the salts, and the volatile oils. The sulphur 
of the sulphates, forming with the hydrogen of the oils, 
sulphuretted hydrogen, and the carbon of the volatile oil 
combining with the oxygen of the sulphuric acid, producing 
partially, if not wholly, carbonates of the bases with which 
that acid was previously combined. 
It is quite evident that the only source of sulphur must 
have been the sulphates, as the water originally contained 
no trace of sulphuretted hydrogen, and the volatile oils 
used were such as peppermint, dillseed, &c, and are com- 
posed only of carbon, hydrogen, and oxygen. 
I will take this opportunity to observe that the remarks 
of Mr. Warington upon distilled aromatic water, published 
in this Journal, are fully borne out by my own experience, 
as to the inutility of the spirit directed to be used by the 
Pharmacopoeia in their preparation, and to the still worse 
method of preparing them extemporaneously by means of 
carbonate of magnesia. The simplest and best plan of 
obtaining quickly the distilled waters used in Pharmacy, is 
by merely agitating the volatile oils with distilled water in 
such proportions only as the water will take up. The 
quantities of volatile oils ordered by the Pharmacopoeia 
are in excess, but by the methods there prescribed the excess 
is removed in the processes of filtration or distillation. 
Pharm. Jourtx. 
