fia, and alumnae, are prepared by (baking tliefe earths in 
water, and adding the camphoric acid in cryftals; boil, 
filter the liquor hot, and concentrate. That of barytes 
fliould be made with the pure earth ; difTolve it in water, 
and add the camphoric acid eryftallized. The campho- 
rats of potafti, 1'oda, and ammoniac, ftiould be prepared 
with the car'oonats diffolved in water; faturate the folu- 
fion with cryftahized camphoric acid; heat, drain,and the 
camphorats are obtained by evaporation and cooling., 
If the camphoric acid which is ufed be very pure, the 
camphorats have no odour ; if otherwife, they will pre- 
fcrve a finell of camphor. The camphorats of alumine 
and barytes leave a fenfe of acidity on the tongue; the 
.others are rather bitter. They are all decompofed by 
caloric; the acid flies off, and is fublimed; the bafe re¬ 
mains pure, except that of ammoniac, which evaporates 
entirely. If urged with the Blow-pipe, the acid burns 
with a blue flame, which, in the camphorat of ammo¬ 
niac, changes at laft to red. They are moftly foluble; 
thofe of lime and magnefia are the leaft fo. -Mineral acids 
difl'olve them all. Alkalis and earths a£t according to 
their affinities for the camphoric acid : the order of affi¬ 
nities is, lime, potaflt, foda, barytes, ammoniac, alumine, 
and magnefia. Many metallic folutions, and feveral of 
the neutral falts, decompofe the camphorats, as the nitrat 
of barytes, molt of the calcareous falts, &c. Thofe of 
lime, magnefia, and barytes, yield their acid to the a&ion 
of alcohol. 
■Fixed and volatile oils difl’olve camphor by the aflift- 
ance of heat. Tliefe folutions, by cooling, gradually de- 
pofit cryftals iu a vegetation fimilar to that which is 
formed in folutions of ammoniacal muriat; namely, a 
middle Item, in which very fine horizontal threads are 
inferted. This kind of feathers, examined by the mag¬ 
nifier, is very beautiful and regular. 
Camphor is one of the moll powerful remedies the art 
of medicine poflefl'es. It diffipates inflammatory tumors 
in a fhort time, by external application. It is ufed as an 
antifpafmodic, and as an antileptic remedy in contagious 
diforders, putrid fevers, and, in general, in all diforders 
which are attended with nervous affeftions, or putridity. 
It is of importance to be known, that camphor often 
mitigates heat and pain in the urinary paflages. It is 
given, triturated with yolk of eggs, fugar, gums, or in 
the ftate of oil of camphor ; and is lbmetimes ufed in the 
-compoiition of diet drinks. 
Of RESINS. 
Volatile oils, expofed to the air, grow thick fooner or 
; later ; what remains, after this fpontaneous evaporation, 
is called re/m. The ancients believed, that, in the con- 
verfion of oils into refins, nothing but water was evapo¬ 
rated ; but it is now known, that there is no refiniftca- 
tion, if the vefl'els which contain them are entirely full, 
or if deprived of the contact of air. The procefs is as 
follows.: The oil abforbs a pretty confiderable quantity 
of oxygen, and lofes a part of its carbon, which, uniting 
..with the oxygen of the atmolphere, furniflies carbonic 
a< id; a proof that a refin is only a volatile oil with a 
greater quantity of oxygen, and a fmaller quantity of 
carbon. 
But refills may be made artificially, by means of nitric 
acid with a volatile oil. Take a glafs tubulated alembic, 
with a receiver proper to preferve liquid and gafeous 
produfls; in the cucurbit of the alembic put fix penny¬ 
weights of volatile oil of turpentine, and dole the aper¬ 
ture with a cork, in which is fixed a fuunel-ftiaped tube 
of glafs; through this introduce, by flow degrees, and 
drop by drop, twelve penny-weights of pure concen¬ 
trated nitric acid: then carbonic acid gas, azotic gas, 
and nitrous gas, will be difengaged. By rectifying the 
produft in the receiver, Pruflic acid is obtained ; and, in 
the retort employed in the rectification, an acid mixture 
will be found, one part ,Qf which cryftallizes in cooling; 
this is oxalic acidj_ the relt is a mixture of nitric and 
S T R Y. 
malic acid. The matter remaining in the cucurbit ufed 
in the firit experiment, is a brownilh mafs of a peculiar 
fmell, of a tenaceous vifcous confidence, analogous to 
reuns. The black colour of this fubftance ariles from 
the fudden precipitation of the carbon ; whereas, in na¬ 
tural refinification, the carbon gradually unites with 
oxygen, and forms carbonic acid, which volatilizes. 
There is ltill a fourth operation in refinification; for 
part of the hydrogen of the oil combines with the oxy¬ 
gen of the atmolphere, forming water which volatilizes 
alfo. 
Refins are inflammable, foluble in alcohol and oils, but 
not in water. Several trees produce them ; they are 
fometimes- liquid, lbmetimes hard. They are obtained 
fometimes by incifion; lbmetimes it is neceffary to diftil 
a part of the tree. The principal fpecies are the follow¬ 
ing: Balfam of Mecca and of Copahu, or Copaiba ; Chio 
turpentine, afforded by the turpentine-tree which yields 
piftachio nuts; Venice turpentine, from the larch-tree; 
and Stralburg turpentine, from the fir. 
In the arts, the turpentine of Chio is diftilled in a 
water-bath, and furnilhes a volatile oil, very white, lim¬ 
pid, and odorous, called ejfence of turpentine. In medi¬ 
cine, a remedy is prepared with turpentine, known by 
the name of boiled turpentine. Put turpentine in a glazed 
pipkin, with three or four times its weight of water; 
boil it till the turpentine has acquired a proper confid¬ 
ence to form a mals, which may be known by throwing 
a little of it from time to time in cold water. Turpen¬ 
tine is alfo uled in the combination called Starkey's foap, 
before defcribed. 
Balfam of Canada differs from the fir-turpentine only 
in its fweeter fmell. 
Pitch. —This is a refinous juice, proceeding from a 
kind of fir called picea, or epicea. There are feveral forts. 
That which is melted and ltrained through lacks is the 
pureft; it is received in barrels, and is then called white 
pitch, or Burgundy pitch. White pitch, mixed with lamp¬ 
black, conftitutes black pitch. White pitch, long kept 
in fufion with vinegar, dries, becomes brown, and forms 
colophony. The dregs of pitch are burned in a fire¬ 
place whole chimney leads into a fmall chamber, termi¬ 
nated by a cone made of cloth : in this halt, the fmoke 
condenles, and forms the fine foot, called lamp-black. 
Galipot, or refin of the pine, affords the loft pine¬ 
apples. Holes are bored in the lower part of this tree, 
through which the refm flows into troughs. Other in- 
cifions are made higher up, when the former afford no 
more. When emitted in the fluid ftate, it is called gali¬ 
pot ; the portion which dries on the tree, in yellowifli 
mafles, is called barras. Tliefe juices are meited, and, 
when thickened by heat, are filtered through ftraw-mats, 
and poured into moulds in fand. They then form malfies, 
called ar cannon, or bray-fee. If water be added, the matter 
becomes white, and forms refm, or pitch refin. Galipot 
is diftilled in the large way in many parts of France, and 
affords an oil, called huile-de-ra&e, or caulking-pitch. The 
tar, which is the empyreumatic oil of this fubicanGe, is 
prepared with the branches and roots of the pine. Till? 
wood of this tree is laid in heaps, covered with turf, and 
fet on fire. The oil, difengaged by beat, not being ca¬ 
pable of efcaping through the turf, is precipitated into a 
fiiallow tub, by means of a channel, and is collefted for 
fale by the name of tar. 
The other refinous fubftances are maftic, from the len- 
tifk or maftic-tree; fandarac, from the juniper; labda- 
num, from the ciftus of Candia; dragon’s blood, from 
the dracaena-draco ; refin anime, from the American jetai- 
ba ; copal, from New Spain ; relin elemi, from America. 
The combination of feveral refins, coloured with cin¬ 
nabar and minium, conftitutes what is called Spanijh 
’wax. To make this wax, take two parts of turpentine, 
two of colophony, one of cinnabar, one of minium, and 
four parts of gum-lac; melt the lac and the colophony, 
then add the turpentine, and mix in the colouring matters. 
