CHEMISTRY. 339 
Of BALSAMS. 
Authors differ as to what conffrtutes a balfam. La 
Grange defines it, a refin United by the aft of vegetation 
with the benzoic acid. There are f'everal fpecies. i. Ben- 
soin ; this is diftinguifhed into two kinds : the benzoin 
amygdaloides, formed of white tears, refembling almonds, 
united by a brown matter; and common benzoin, which 
is brown, and without tears; it emits a very agreeable 
fmell, when fufed or touched with a hot needle. The 
benzoin comes from the kingdom of Siam, and the ifland 
of Sumatra. It affords very little volatile oil on account 
of its folidity. Boiling water extrafts an acid fait, in the 
form of needles, of a ltrong fmell, which cryftallizes by 
cooling. It is likewife obtained by fublimation, and is 
then called flowers of benzoin. This operation is made 
in two glazed earthen pots, placed one above the other, 
and ciofed at the place of junftion with paper. The fub¬ 
limation muff be performed with a gentle heat, other- 
wife the fait, will be brown. The paper cone, formerly 
ufed as a fubliming chimney, inffead of the upper pot, 
caufes the lofs of a great part of the concrete acid. We 
bave explained the properties of tins acid in p. 325. Ben¬ 
zoin, diftilled in a retort, affords a very acid phlegm, a 
concrete and brown fait of the fame nature, with a brown 
and thick oil. The refidual coal contains fixed alkali. 
Benzoin difl'olves in alcohol; and its tinfture, precipi¬ 
tated by water, affords the lac ‘virginale. The fait of 
benzoin, or benzoic acid, is ufed as a good incifive re¬ 
medy in pituitous diforders of the lungs and veins. 
Its oil is difcuflive, and is externally applied in paraly¬ 
tic diforders. 
2. Balfam of Tolu, Peru, or Carthagena. It is im¬ 
ported either in cocoa-nut (hells, or in yellowifh tears, 
or in a fluid ftate. It flows from the toluifera, placed 
by Linnaeus among the decandria monogynia. It may 
be extrafted from the (hells, by fteeping them in boiling- 
water, which renders it fluid. It comes from South Ame¬ 
rica, in the track between Carthagena and Hombre de 
Dios, called by the iflanders Tolu, and by the Spaniards 
Honduras. By analyzing, it affords the fame produfts 
as benzoin, and more particularly the concrete acid. It 
is made into a fyrup, and is ufed in diforders of the 
lungs. Some naturalifts diftinguifh balfam of Peru from 
that of Tolu. The acid of thefe two ball'ams does effen-, 
tially differ from benzoic acid. 
3. Storax calamita is in tears, either red and clean, or 
brown and unftuous. Its fmell is very ltrong. It flows 
from the oriental liquid amber, a plant very little known. 
Duhamel obferved a juice of a (imilar odour flow from 
the aliboufier. Newman analyzed the (lorax calamita, 
and obtained a very fmall quantity of effential oil, a con¬ 
crete acid fait, and a thick oil. This balfam is applied 
to the fame ufes as benzoin, and is more particularly 
confumed by perfumers. It was formerly imported en- 
clofed in reeds or canes; we now receive it in the form 
of loaves, or irregular maffes, of a reddifh brown co- 
lour,,mixed with fome tears of a lighter colour, and of 
a very agreeable fmell. 
4. Liquid (lorax, or common ftorax. Bouillon La 
Grange, who has analyzed this fubltance, fays, that 
it is almoft entirely volatile in the fire, and emits an 
odour (imilar to mat of benzoic acid. Heated in a 
pneumatic apparatus, it affords, 1. An acid phlegm hav¬ 
ing the agreeable odour of benzoic acid. 2. A white, 
light, ccrid, and penetrating, oil. 3. A more deeply co¬ 
loured, concrete, (lightly acid,-oil. 4. A faline fubltance 
fublimed into the neck of the retort. 5. A mixture of 
carbonic acid and carbonated hydrogen gales. 6. A very 
light charcoal. If (torax be expoled to atmofpheric air, 
a pellicle is foon formed on its fur face which gradually 
acquires a folid confidence. The ltorax becomes granu¬ 
lar, very bitter, and lets odorous. It appeal s to abfiorb 
oxygen from the atmol'pliere, which converts it more 
completely into the ftate of a refin. Thefe changes take 
1 
place more fpeedily, if oxygen gas be employed inftead 
of atmofpherical air. Very beautiful cryitals may be ob¬ 
tained by diffolving it in water and evaporating the fo- 
lution (lowly. Alkalis, and the mineral acids, produce a 
very marked aftion on ltorax. The alkalis unite wdth 
the benzoic acid and form benzoats, while the acids dif- 
folve the lime that is found in it, and give to it a red co¬ 
lour. Water precipitates this fubltance from its folution 
in alcohol. If the precipitate be left expoled to atmof¬ 
pherical air, it becomes firft brown, and afterwards of a 
deep red colour. The refidue burns on lighted coals, 
and emits a (lightly aromatic odour. A white earthy 
fubltance is left behind. Water has no aftion on this 
matter; alkalis give it a deep colour; the fulphuiic, ni¬ 
tric, and muriatic, acids diffolve the earthy matter; am¬ 
moniac forms in it a precipitate which has all the charac¬ 
ters of magnefia. Oxalic acid Ihews in it the prefence 
of lime. 
5. Artifi.ini balfam of vanilla. This is the filique of 
a plant, which climbs and fallens round trees like ivy. 
It comes from America ; and is found in Peru, Mexico, 
and St. Domingo. It furnilhes benzoic acid. 
Of GUM RESINS. 
Gum refills are juices mixed with refin, and an extrac¬ 
tive matter, which has been taken for a gummy fubltance. 
They never flow naturally from plants, but are extrafted 
by incifion, in the form ofemullive white, yellow, or red, 
fluids, which dry more or lefs quickly. Water, alcohol, 
wine, or vinegar, diffolve them only in part. They differ 
in the proportion of refin and extraft, and their analyfis 
affords various refults. 
Gum refins may be divided into two genera: 1. Such 
as are foluble and fetid ; as, gum ammoniac, affafetida, 
&c. 2. Such as are purgative; as, fcammony, euphor- 
bium, gum guttae, See. The gum refins are very nume¬ 
rous 5 the principal fpecies are, 
1. Olibanum confilts of yellow tranfparent tears, of a 
very difagreeable fmell. The tree which affords it is 
fuppofed to be the cedar with cyprefs leaves. By diftilla- 
tion, a fmall quantity of volatile oil, together wdth an 
acid fpirit, are obtained, and the coally refidue, arifing 
from the extractive part, is very conliderable. It is ufed 
in medicine for fumigations. 
2. Galbanum is a fat juice, of a brown yellow colour, 
and naufeous fmell, brought to us from the Levant. In 
Syria, Arabia, and at the Cape of Good Hope, it flows 
from incifions made in a ferulaceous plant, named bubon 
galbanum by Linnaeus. Diftilled with a naked fire, it 
affords a blue effential oil, which afterwards becomes 
red ; and alio an acid fpirit, with a ponderous empyreu- 
matic oil. It is a very good difcuflive remedy, and is 
powerfully antifpafmodic. 
3. Scammony is of a biackifti grey colour, a ftrong and 
difagreeable fmell, a bitter and very acrid talle. The 
Aleppo fcammony is diftinguifhed by its greater purity 
from that of Smyrna; which is ponderous, black, and 
mixed with foreign fubftances. It is extrafted from the 
convolvulus fcammonia of Linnaeus. The root of this 
plant, cut in pieces, and preffed, affords a white juice, 
which is black when dried. Tha different fpecimens of 
fcammony contain various proportions of extraft and 
refin, and its medical eftefts differ accordingly. It is 
preferibed as a purge, in the dofe of from four to twelve 
grains. Mixed with a fweet extraft, fuch as that of li¬ 
quorice, it forms the common diagridium ; the juice of 
quinces is likewile ufed for this purpofe. The common 
mode of adminiftering it, is after previous trituration 
with fugar and lweet almonds. 
4. Gum guttae is yellow, reddiffi, without fmell, 
and of a very acrid and corrofive tafte. It comes from 
Siam, China, and the ifland of Ceylon. It is extrafted 
from a large tree, not much known, called by the natives 
coddam pulli. It contains much refin, which renders it 
ltrongly purgative, in a dofe of from four to fix grains. 
