50 ORD. XXV. Lomentacez. MYROXYLON PERUIFERUM. 
time it condenses and hardens into resin, and is then denominated, Dry 
white balsam, or balsam of Tolu, by which name it is distinguished in the 
druggists’ shops. M. Valmont de Bomare says, in his Dictionary of 
Natural History, that if an extract be made from the bark, by boiling it in 
water, it remains liquid, and of a blackish colour, known under the appella- 
tion of black Peruvian balsam.* 
Sensible and Chemical Properties. Genuine Peruvian balsam is of a deep 
reddish brown colour, very viscid, and of the consistence of honey when first_ 
taken from the comb; it has a warm, aromatic, and slightly bitter taste, and 
when swallowed leaves a somewhat acrid sensation in the throat; its odour 
is very fragrant. Distilled with water, it yields a small quantity of reddish 
limpid oil, and benzoic acid sublimes in the neck of the retort; the remaining 
matter is resin: when boiled with water, the liquid becomes acidulated, 
reddens vegetable blues, and deposits on cooling, crystals of benzoic acid. 
It dissolves completely in ether, and also in alcohol, but the latter requires 
to be in considerable quantities. The alkalies and their carbonates, form 
with it thick masses, which, on the addition of sulphuric acid, lets fall a 
resinous matter, and benzoic acid, crystallizes. Treated with nitric 
and muriatic acids, the presence of prussic acid is detected, benzoic acid 
sublimes, and the residual matter is artificial tannin. Mr. Hatchett found 
that when this is heated with sulphuric acid, artificial tannin is also formed, 
and the charcoal remaining amounts to no less than 0,64 of the original 
weight of the balsam.t At 550° the balsam begins to boil when exposed 
to heat in a water-bath, and some gas is discharged. At 594° the oil mixed 
with a little water, comes over pretty fast. Lichtenberg kept four ounces 
of balsam at the temperature of 617° for two hours, and obtained two ounces 
of a yellowish oil, and a crystallized mass of benzoic acid ; which, together 
with the water, weighed six drachms and a half. The gas obtained amounted 
to fifty-eight ounce measures, thirty-eight being carbonic acid; the rest 
burnt like oleifiant gas. From the analysis of Stoltze, 1000 parts of balsam 
consist of 24 of brown, nearly insoluble resin, 207 of soluble resin, 690 of a 
peculiar kind of volatile oil, 64 of benzoic acid, and 6 of extractive matter. 
Tolu Balsam. This balsam was formerly supposed to be the produce ofa. 
* A fictitious composition, a mixture of resin, and some volatile oil, scented with ben- 
zoin, is often sold for the genuine Peruvian balsam, and the fraud is not readily detected. 
+ Hatchett. Phil. Trans. 1806. 
