: as 
284 ” Chesnséed isis Ge Sa 
vegetable bodies, containing a large proportion of resin, are known 
to resist decomposition for ages, the combustibility of the bark and 
its enduring qualities when exposed to heat and moisture, — 
questionably due to its resinous ingredient. 
The resin constitutes a great proportion of the bark; so aa a 
proportion indeed, that when heated in close vessels, the whole mass 
appears to melt. It is singular that the resin, when so abundant, 
never manifests itself by a spontaneous exudation from the tree. 
In the course of some of the experiments detailed above, 1 spread 
a portion of the resin upon a paper, and placed it upon a warm stove, 
with a view to dry it effectually. In this situation it was accidentally 
subjected to so hig a temperature, that a portion of the resin began 
ove fe 
the whole saree of the resin was a ciechet “with brilliant —_ 
crystals, radiating from every elevated point, and crossing each 0 
at possible’ angle. This crystalline matter resembled a 
waged | 
acid so closely that at first I supposed it-was that substance, and con 
sequently, the resin containing it belonged to the class of balsams. 
A subsequent examination, however, convinced me that that supposi- 
tion was erroneous although it was not — of the — nature of 
the substance. 
It is extremely difficult to obtain this body in large quiintiti and 
no means that I have applied, have proved more effectual than 
by which it was first procured. It possessed the following properties? 
It experienced no change by exposure % the atmosphere for weeks. 
It was destitute -of taste, and, at common temperatures, of smell. 
When eet heated, it afforded the peculiar odor of the resin. 
: us vapors, arising from it, could be inhaled without any 
of that irritation of the respiratory ‘organs which the vapor of benzo1e 
acid occasions. It was absolutely insoluble in cold'water, and very 
sparingly so, if at all; in hot. It combined instantly with alcohol and 
ether. Digested with dilute muriatic and nitric acids, imperfectly 
crystallized compounds were > formed, which possessed a strong bitter 
taste. 
If this examination ise too imperfect to authorise any decision upon 
the chemical nature of this substance, it is, I think, nevertheless cou- 
-clusive as to. those properties which distinguish it from + the be Zoic 
acid, which it so much resembles in appearance. ‘ 
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