Reaction of the Essential Oils with Sulphurous Acid. 283 | 
washing with ammonia will not entirely remove the power of yielding 
sulphuric acid; and the total absence of the sulphurous smell de- 
monstrates that the sulphurous acid either enters into an intimate 
combination with the oil, or acquires oxygen sufficient to convert it 
into sulphuric or hyposulphuric acid. 
Those essential oils which contain oxygen, are most affected by 
the action of sulphurous acid. 
Both the oils of cloves and cinnamon, after admixture with sul- 
phurous ether and subsequent distillation, gave, on analysis, precipi- 
tates of sulphate of barytes. In the case of cloves, the precipitate 
amounted to one seventh of the whole weight. 
By distilling camphor with alcohol and sulphuric acid, I obtained 
a yellow liquid, which; by washing with ammonia and evaporation, 
in order to get rid of the sulphurous ether, yielded an oil. The oil, 
by standing, separated into two portions, one solid, the other liquid. 
The solid portion resembled camphor somewhat in smell, but differed 
from it by melting at a much lower temperature, becoming com- 
pletely fluid at 175°. 
I found that the essential oils of cimnamon and cloves possessed an 
antiseptic power, quite equal to that of kreosote, and that their aque- 
ous solutions, when sulphated, were even superior to similar solutions 
of that agent. 
One part of milk mingled with four parts of a saturated aqueous 
solution of the sulphated oil of cloves, remained after five days sweet 
and liquid, while another portion of the same milk became curdled 
and sour within twenty four hours. Having on the 2d day of July 
added two drops of oil of cinnamon to an ounce measure of fresh 
milk, it remained liquid on the 11th; and, though it finally coagula- 
ted, it continued free from bad taste or smell till September, al- 
though other portions of the same milk had become putrid. A half 
ounce of milk, to which a drop of sulphurous oil of turpentine had 
been added, remained free from coagulation at the end of two days, 
while another portion, containing five drops of pure oil of turpentine, 
became curdled and sour on the next day. 
A number of pieces of meat were exposed in small wine glasses, 
with water impregnated with solutions of the various essential oils. 
‘Their antiseptic power seemed to be in the ratio of their acridity. 
The milder oils seemed to have comparatively little antiseptic power, 
unless associated with the  eulplngms acid, which has long been 
known as an antiseptic. 
