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SUGAR. 
cess, from Use sap of (lie acev saceharimim, or 
sugar maple-tree, which abounds in the woods. 
(See Ac ur.) Every forty pounds of sap 
yields about a pound of sugar; so that it is 
not one sixth so rich as the "East India sugar- 
cane. & 
‘ he sap ought never to be kept longer than 
twenty-dour hours after it is procured from 
die tree, it is improved by straining through 
a cloth. It is put into large flat kettles,- 
mixed usually with quicklime, white of egg, 
and new nolle. A spoonful ol slacked lime, 
the white of one egg, and a pint of new milk, 
are sufficient for iittecn gallons of sap. A little 
butter is added to prevent the sap from boil- 
ing over. When boiled down sufficiently, it 
is allowed to grain, or form into small crystals, 
which constitute raw sugar, and then purified 
in the usual manner. 
4. The raw sugar imported into Europe 
is still farther puriiied. It is dissolved in wa- 
ter, mixed with lime, clarified by means of 
bullock’s blood, boiled down to a proper con- 
sistency, skimming off the impurities as they 
rise to the top, and then poured into unglazed 
conical earthen vessels, where it is allowed to 
grain. The point of file cone is undermost, 
and perforated to allow the impurities to se- 
parate. 1 he base of the cone is covered with 
moist clay ; firewater of which gradually lil- 
tres through the sugar, and displaces a quan- 
tity ot impure liquid. The sugar thus purified 
is called loaf-sugar. When redissolved, and 
treated in the same way a second time, it it 
called refined sugar. 
5. Sugar, thus procured, lias a very strong 
sweet taste. When pure it has no smell. Its 
colour is white; and when crystallized it is 
somewhat transparent. It lias often a con- 
siderable degree of hardness •. but it is always 
so brittle that it can be reduced without dif- 
ficulty to a very fine powder. When two 
pieces of sugar are rubbed against each other ! 
in the dark, a strong phosphorescence is vi- I 
sible. 
Sugar is not altered by exposure to the at- 
mosphere, excepting only that in damp air it j 
absorbs a little moisture. j 
It is exceedingly soluble in water. At the j 
temperature of 48°, water, according to Mr. 
Wenzel, dissolves its own weight of sugar. 
The solvent power of water increases with its 
temperature; when nearly at the boiling- 
point, it is capable of dissolving any quantity 
of sugar whatever. Water thus saturated 
with sugar is known by the name of syrup. I 
Syrup is thick, ropy, and very adhesive ; 
when spread thin upon paper it soon dries, and 
forms a kind of varnish, which is easily re- 
moved by water, its specific caloric, accord- 
ing to the experiments of Dr. Crawford, is 
1 .08(5. When syrup is sufficiently concen- 
trated, the sugar which it contains precipitates 
in crystals. The primitive form of these 
crystals is a four-sided prism, whose base is 
a rhomb, the length of which is to its breadth 
as 10 to 7 ; and whose height' is a mean pro- 
portion between length and breadth of the 
base. The crystals are usually four or six- 
sided prisms, terminated by two-sided, and 
sometimes by three-sided summits. The spe- 
cific gravity of sugar is 1.4045. 
When heat is applied to sugar it melts, 
swells, becomes brownish black, emits air-bub- 
bles, and exhales a peculiar smell, known in 
French by the name of caromel. At a red 
beat it instantly bursts into flames with a kind 
of explosion. The colour of the flame is white 
with blue edges. 
0. Sugar, as far as is known, is not acted 
poo by oxygen gas. The effect of the sim- 
U 1 . ... „ 
pie combustibles on it has not been tried; 
but it does not appear to be great. Azotic 
gas or the metals have no sensible actions on 
it. 
The lower compartment of Plate Saw-mill, 
&c. represents a mill for squeezing the juice 
from the sugar-canes. AB DE is a strong’traine 
or wood, (be lower part D of which is a large 
block : the upper surface of this is cut out into 
a bason, to collect and receive the juice of the 
canes; which is expressed by the three rollers 
EG II, whose lower pivots work in sockets in 
the block D, and the upper sockets are fixed 
in the beam E. The sockets of the middle 
roller are fixed firmly in the beams D and E. 
J lie sockets of tiie other two arc held between 
two wedges ab, put in in contrary directions, 
the small end of one wedge being on (he 
same side with the large end of the other. By 
this means the rollers can always be set near- 
er together, or farther from each other. 
When it is wanted to set the outside rollers 
nearer the middle roller, drive out that 
wedge which is nearest the middle roller, and 
gar and lime. Sulphuric acid precipitated the 
lime in the state ofsulplnit, and restored the 
original taste of the sugar. Wlifn the com- 
pound or sugar and lime was evaporated to 
dry ness, a semitransparent tenacious syrup re- 
mained which had a rough bitter taste, with a 
certain degree of sweetness. 
drive the other in; and the cohtrarv when 
they are wanted farther apart. The rollers 
are usually of cast iron, and each has a cog- 
wheel, as I, on its upper end, which causes 
them all to turn together, the power of the 
first mover being applied to the middle one 
by a shaft K. 
\\ hen the machine is at work, a man 
stands on each side of it. ' The one in the 
front takes the canes, and puts them in be- 
tween the rollers EG, which, as they turn, 
draw the canfis through, and express their 
juice. The man behind them directs the 
ends of the canes back between the rollers GII, 
which are somewhat nearer together than the 
others; and as they come through, a third 
man carries them away. The juice runs 
down the rollers info the reservoir, and is con- 
veyed by the trough L to the boiling-house. 
It must be observed, that the reservoir in the 
top of the block D must be only cut in chan- 
nels round the outside of the rollers ; being 
left the full height near the centres, to pre- 
vent the liquor running down, and getting 
out between the wedges ab. 
When a sugar-mill is worked by wind, the 
shaft K is connected with the vertical shaft of 
the mill. If by horses, the levers they work 
from are fixed to the shaft K ; and either the 
horse-walk is raised above ground higher than 
the trough L, or the juice is conveyed by a 
pipe laid under the walk. 
Sugar-mills that are worked by a water- 
wheel, or steam-engine, have a bevelled 
wheel fi:yqrj upon the shaft K, and another 
upbntlie wheel or engine shaft which turns it. 
The earths proper do not seem to have any 
action whatever on sugar; but the alkaline 
earths unite with it. When lime is added to 
a solution of sugar in water, and the mixture 
boiled for some time, a combination takes 
place. The liquid still indeed retains its 
sweet taste; but it has acquired also a bitter 
and astringent one. A little alcohol added to 
the solution produced a precipitate in white 
flakes, which appeared to be compound ofsu- 
Ihe fixed alkalies combine with sugar, and 
form compounds, not unlike that which has 
been just described. Potass destroys the sweet 
taste of syrup more completely than lime; 
but when it is neutralized by sulphuric acid, 
and the sulphat precipitated" by alcohol, .the 
sweet taste is completely restored. When 
alcohol is agitated with the compound of su- 
gar and potass dissolved in water, it refuses to 
unite with it, but swims on the top in a stale of 
purity. 
r ! he acids are capable of dissolving sugar, 
and those which are concentrated decom- 
pose it. Sulphuric acid very soon acts upon 
it ; water is formed, and perhaps also acetic 
acid ; while charcoal is evolved in great abun- 
dance, and gives the mixture a black colour, 
and a considerable degree of consistency. 
The charcoal may be easily separated by di- 
lution and filtration. When heat is applied, 
the sulphuric acid is rapidly converted into 
sulphureous acid. 
Nitric acid dissolves it with an effervescence 
occasioned by the evolution of nitrous gas* 
and converts it info malic and oxalic acids! 
T >0 grains of sugar, treated with six ounces 
of nitric acid diluted with its own weight 
of water, and cautiously heated, separat- 
ing crystals as they formed, yielded 
280 grains of oxalic acid'; so that 160 parts 
of sugar yield by this treatment 58 parts of 
oxalic acid. When liquid oxymuriatic acid 
j is poured upon sugar in powder,' it isdissolved, 
[ and immediately converted into malic acid ; 
j and the oxymuriatic acid is converted into 
I common muriatic acid. 
Sugar absorbs muriatic acid gas slowly, and 
assumes a brown colour and. very strong 
smell. The vegetable acids dissolve it ; but 
seemingly without producing any alteration 
on it. 
The action of the oxides of carbon and 
azole upon sugar has scarcely been exa- 
mined. 
Sugar is soluble in alcohol, but not in so 
large a proportion as in water. According 
to \\ enzel, four parts of boiling alcohol dis- 
solve one of sugar. It unites readily with oils, 
and renders them miscible with water. A 
moderate quantity of it prevents, or at least 
retards, the coagulation of milk ; but Scheele 
discovered that a very large quantity of su- 
gar causes milk to coagulate. 
r l he hydrosulphurets, sulphurets, and phos- 
plnuets of alkalies and alkaline earths, seem 
to have the property of decomposing sugar, 
and of bringing it to a state not very different 
from that of gum. Mr. Cruickshank intro- 
duced a quantity of syrup into a jar standing 
over mercuiy, and then added about an equal 
quantity of phosphuret of lime. Phosphu- 
reted hydrogen gas was immediately extri- 
cated. In eight days the syrup was with- 
drawn : it had lost its sweet taste, and ac- 
quired a bitter and astringent one (the taste of 
I phosphuret of lime). . From this solution alco- 
! hoi threw down white flakes, very much re- 
j sembling those of mucilage separated from 
| water by the same liquid. A little sugar was 
