on a Substance possessing the Properties of Tannin. 305 
Grains. 
A. An essential oil which had an odour somewhat re- 
sembling a mixture of lavender and peppermint, about - 3 
B. A compact and very hard sort of coal in small 
fragments ----- 53 
C. And a blackish brown substance of a resinous 
appearance 49 
105 
From this statement it appears, that there was an increase in 
the weight amounting to five grains, which I attribute partly to 
oxygen united to the carbon, and partly to a portion of water so 
intimately combined with the last product, that it could not be 
expelled from it by heat without subjecting it to decomposition. 
The properties of this substance were as follows : 
1. It was extremely brittle, had somewhat of the odour of 
caromel, the flavour was astringent, and it speedily dissolved 
in cold water, and formed with it a permanent dark brown 
solution. 
2. This solution yielded very dark brown precipitates by the 
addition of sulphate of iron, acetite of lead, muriate of tin, and 
nitrate of lime. 
3. Gold was copiously precipitated by it from its solution in 
the metallic state ; and 
4. By solution of isinglass, the whole was completely preci- 
pitated, so that after three or four hours, a colourless water 
only remained. 
The precipitate was nearly black, and was insoluble in boiling 
water; from which property, as well as from the effect pro- 
duced upon prepared skin by the solution, it was evident, that 
the substance thus obtained from camphor, was a variety of 
mdcccv. R r 
