Encyclopaedia Britannica, or, a Dictionary of arts, sciences, and miscellaneous literature : enlarged and improved. Illustrated with nearly six hundred engravings > Volume 19, Scripture-SUG

S tr G [ 803 ] S U G
Sugar, purities may be thoroughly feparated. But if the liquor
'_l were fuffered to boil with violence, the impurities would
again incorporate with it. It is known to be fufficiently
heated when the fcum begins to rife in blitters, which
break into white froth, and appear generally in about
40 minutes. The fire is then fuddenly extinguifhed by
means of a damper, which excludes the external air, and
the liquor is allowed to remain about an hour undifturb-
ed, during which period the impurities are collefted in
fcum on the furface. The juice is then drained off ei¬
ther by a fyphon or a cock j the fcum being of a tena¬
cious gummy nature, does not flow out with the liquor,
but remains behind in the clarifier. The liquid juice is
conveyed from the clarifier by a gutter into the evapo¬
rating boiler, commonly termed the grand copper ; and
if it has been obtained from good canes it generally ap-
2(j pears tranfparent.
and four In the evaporating boiler, which fliould be large
coppers. enough to receive the contents of the clarifier, the liquor
is allowed to boil; and as the fcum rifes it is taken off.
The fcumming and evaporation are continued till the
liquor becomes finer and thicker, and fo far diminifhed
in bulk that it may be eafily contained in the fecond
copper. When put into the fecond copper, it is’ nearly
of the colour of Madeira wine ; the boiling and fcum¬
ming are continued, and if the impurities be confider-
able, a quantity of lime-water is added. This procefs is
carried on till the liquor be fufficiently diminilhed in
quantity to be contained in the third copper. After
being purified a third time, it is put into the fourth cop¬
per, which is called the teache, where it is boiled and
evaporated till it is judged fufficiently pure to be re¬
moved from the fire. In judging of the purity of the
liquor, many of the negroes (fays Mr Edwards) guefs
folely by the eye (which by long habit they do with
great accuracy), judging by the appearance of the grain
on the back of the ladle : but the praftice moft in ufe is
to judge by what is called the touch ; i. e. taking up
with the thumb a fmall portion of the hot liquor from
the ladle ; and, as the heat diminilhes, drawing with
the fore-finger the liquid into a thread. This thread
will fuddenly break, and fhrink from the thumb to the
fufpended finger, in different lengths, according as the
liquor is more or lefs boiled. The proper boiling height
for ftrong mufcovado fugar is generally determined by
a thread of a quarter of an inch long. It is evident,
that certainty in this experiment can be attained only
by long habit, and that no verbal precepts will furniffi
/ any degree of fldll in a matter depending wholly on con-
^ ftant practice.
After being The juice being thus purified by paffing through the
clarified it clarifier and four coppers, it is poured into coolers,
is cooled, ndjJeh are ufually fix in number. The removal from
andfreed ’ teache to the cooler is called Jlriking. The cooler
from its is a (hallow wooden veffel feven feet long, from five to
melafles. fix wide, about 11 inches deep, and capable of contain¬
ing a hogffiead of fugar. As the liquor cools, the fu¬
gar grains, that is, collects into an irregular mafs of im¬
perfect cryftals, feparating itfelf from the melaffes. It
is then removed from the cooler, and conveyed to the
curing-houfe, where the melaffes drain from it. For
receiving them there is a large eiftern, the (loping fides
of which are lined with boards. Directly above the ci-
ftern a frame of joift-work without boarding is placed,
®n which empty hogflieads without heads are ranged.
The bottoms of thefe hogffieads are pierced with 8 or | Sugar. ^
10 holes, in each of which the (talk of a plantain leaf 1 »
is fixed fo as to proje£t fix or eight inches below the
joifts, and rife a little above the top of the hogfhead.
The hogtheads being filled with the contents of the
cooler, confiding of fugar and melaffes, the melaffes be¬
ing liquid, drain through the fpongy dalk, and drop in¬
to the cidern. After the meiaffes are drained oft, the
fugar becomes pretty dry and fair, and is then called
mufcovado or ra w fugar.
We have defcribed the procefs for extracting fugaf,
which is generally adopted in the Britilh Wed India
iftands, according to the lated improvements *, and have
been anxious to prefent it to our readers in the iimpleft
and moft perfpicuous form, that it might be intelligible
to every perfon j and have therefore avoided to mention
the obfervations and propofed amendments of thofe who
have written on this fubject. Had we done fo, we
(hould have fwelled the prefent article to too great a
fize, without accomplilhing the purpofe which we have
in view j for our intention is not to inftrucff the plant¬
ers, but to give a diftindt account of the moft approved
methods which the planters have generally adopted.
But though we judge it ufelefs to trouble our readers
with all the little varieties in the procefs which different
perfons employ, we flatter ourfelves it will not be dif-
agreeable to learn by what methods the French make 2g
their fugar purer and whiter than ours. A quantity of Method of
fugar from the cooler is put into conical pans or earthen purifying
pots, called by the French formes, having a fmall per-
foration at the apex, which is kept clofed. Each cone,
reverfed on its apex, is fupported in another earthen
veffel. The fyrup is ftirred together, and then left to
cryftallize. At the end of 15 or 16 hours, the hole in
the point of each cone is opened, that the impure fyrup
may run out. The bafe of the fugar loaves is then \.?l-chaptal's
ken out, and white pulverized fugar fubftituted in its Chemi/lry,
(lead •, which being well preffed down, the whole is co-va1, ll1,
vered with clay moiftened with water. This water fil¬
ters through the mafs, carrying the fyrup with it which
was mixed with the fugar, but which by this manage¬
ment flows into a pot fubftituted in the place of the firft.
This fecond fluid is called fine fyrup. Care is taken to
moiften and keep the clay to a proper degree of foftnefs
as it becomes dry. The fugar loaves are afterwards ta¬
ken out, and dried in a (love for eight or ten days j af¬
ter which they are pulverized, packed, and exported to
Europe, where they are dill farther purified. The rea-
fon affigned why this procefs is not univerfally adopt¬
ed in the Britiffi fugar iflands is this, that the water
which dilutes and carries away the melaffes diffolves and
carries with it fo much of the fugar, that the difference
in quality does not pay for the difference in quantity.
The French planters probably think other wife, upwards
of 400 of the plantations of St Domingo having the ne-
ceffary apparatus for claying and a&ually carrying on
the fyftem. 29
The art of refining fugar was firft made known to the The art of
Europeans by a Venetian, who is faid to have received refin.ing fll“
100,000 crowns for the invention. This difcovery wasf
made before the new world was explored ; but whether VenePai,.
it was an invention of the perfon who firft communica¬
ted it, or whether it was conveyed from China, where
it had been known for a confiderable time before, can¬
not now perhaps be accurately afcertained. We findmb
5 I 2 mention..