348 Comparative Analysis of the Gum Resins. 
least, that the myrrh,used. in commerce comes from some 
species. of balsam trees.—Lamarck, Encyclopédie Métho- 
digue, art. Balsamicr Kafal. 
The myrrh, which was. the object of my researches, was 
in tears of varied transparency, ofa reddish-vellow colour, 
of an aromatic taste, and slightly bitter. On breaking some 
of the largest pieces, we,frequently remark a white nucleus 
marked with, lines,:.this part, more or less opake, burus 
with a great flame,, while the transparent tears act in the 
fire in the,same manner.as the gums. We also at times 
meet. with.almost colourless pieces, soluble in water, and 
having the taste of mytrh,and which are not gum arabic as 
has been supposed; but rather a peculiar gum, similar to 
that which exists.in- myrrh, and the, properties of which I 
shall presently detail. 
From this physical examination of myrrh it should secm 
that this subsiance is very variable in,its composition. 
§ 1, Thirty grammes-of;myrrhogradually heated until 
the retort became, red, yielded ten grammes of a brown 
heavy empyreumatic oil, ten grammes of a red liquid which 
greens the syrup of violets, yields ammonia when we mix 
potash with it, and acetate of potash mixed with oil if we 
evaporate the liquor. Hence it follows that this aqueous | 
product is composed of ammonia in excess, acetic acid, and 
empyreumatic oil. 
The charcoal remaining in the retort occupied less space 
than the myrrh employed: it was compact, irisated and 
brilliant, and weighed seven grammes 1: when incinerated 
it produced 1-6 gramme of white ashes, which furnished 
with water seven centigrammes of sulphate of potash con- 
taiuing a smal] quantity of subcarbonate of potash. 
That part-of the ashes which was insoluble in water was 
entirely dissolved in nitric acid with effervescence, owing 
to an extrication of carbonic acid, which held a little sul- 
phuretted hydrogen, proceeding of course from the decom- 
position of a small quantity of sulphate of potash by char- 
coal and lime. 
‘When ammonia was poured into the nitric solution, no- 
thing very remarkable was produced. The subcarbonate 
of potash separated from it all the carbonate of lime which 
enters singly into the composition of these _lixiviated 
ashes. 
§ JIT. A. Fifty grammes of myrrh distilled with water 
yielded a product having the smell of myrrh, and on whieh 
there floated a little volatile oil. 
B. The residue of this distillation was thrown on a filter, 
and 
