160 
SELECTED ARTICLES. 
sistency, and translucency of common rosin; but with a higher 
and more lively reddish colour. Its odour recalls, but faintly, 
that of cinnamon; its taste is bitter and disagreeable, yet re- 
calling that of the oil from which it is derived. Its aqueous 
solution does not redden litmus; nor, when acidulated with 
nitric acid, does it yield a precipitate with nitrate of barytes. 
Of this substance ten grains were exposed to the process 
above mentioned, for the detection of sulphuric acid, and 
were found to yield a precipitate of 6.5 grains of sulphate of 
barytes. 
It may be worth while to mention, that in boiling the 
sulphated oils with nitric acid, compounds are formed finally, 
which resist the further action of the acid, and are only to be 
decomposed by the assistance of a nitrate and deflagration. I 
conjecture that these compounds will be found to merit 
classification as ethers formed by an oxacid of nitrogen. 
One of my pupils, in examining one of the compounds thus 
generated, was, as he conceived, seriously affected by it, suf- 
fering next day as from an over dose of opium. He also 
conceived that a cat, to which a small quantity was given, was 
afiected in like manner. 
I had prepared an apparatus with the view of analyzing 
accurately the various compounds above described or alluded 
to, by burning them in oxygen gas; when, by an enduring 
illness of my assistant, and subsequently my own indis- 
position, I was prevented from executing my intentions. 
