The Forest Republican. [volume] (Tionesta, Pa.) 1869-1952, 1890-10-01
TIE TESTING OF SUGAR
ESTIMATING SUGAR DUTIES IN
UNCLE SANS LABORATORY.
The Different Kinds of Sugar and the
Method of AnaIyzinG Fhem-Au
Ingenious Process.

metnOu OF Analynlng Inem-hu
Ingenious Process.
There are many varieties Of sugar, for
the term is used generically to designate
the sweet products obtained from GER
tain vegetables aud most fruits. Thus
we have the cane sugar, from sugar cane;
beet sugar, grape sugar, maple sugar,
melon sugar, palm sugar, date sugar, sor
ghum sugar, maize sugar and Others less
commonly known.
The one, however, which is Of the
greatest importance, and whose use we
are most familiar with, is cane sugar. To
it, therefore, we may devote our princi-
pal attention.
The sugar which comes to New York
is principally exported from Cuba.
Smaller quantities are received from 9th
er of the West Indian islands and Brazil.
In still smaller amounts sugars are sent
to this country from China and some of
the islands of the Pacific.
The origin of the sugar having been
ascertained, it is but natural that we
should expect to see it along the docks
Of our river front.
The incidents of its journey can be of
no interest to us. In the dark hold of
some vessel, probably sailing ship, as
the days quickly follow the nights, in
storm or in calm, the sugar remains in
Its package, unconscious alike of the
anxiety of the seamen or of the tedious
monotony which makes an ordinary sea
voyage so hard to be endured. At the
wharf, as each packages comes ashore, it
is marked by the Government inspector
chosen for this special duty.
Every fourth hogshead or barrel is laid
aside, and when the packages are smaller,
such as bags, ceroons or mats, more fire.
1uent parcels are selected for sampling.
Then long tube, called trler, is run
directly through the central portion, from
end to end, of cack package selected.
Every trierful constitutes an entire sam
pie. The sugar thus extracted is packed
in small tin boxes; these again are placed
in wooden chests, and are sent to the ex-
animation room as rapidly as possible.
The utmost dispatch throughout the en-
ard ending with the polarization, is in
sisted on in order to avoid the drying out
of the water or moisture contained in
the sugar; otherwise higher degree of
polarization, and in consequence higher
rate of duty, would follow. As the inn
porters generally examine the sugar in
their own laboratories, every precaution
is taken by the Government to obtain
correct results.
In the examination room, the sugar is
thrown on the fiat surface of long table
aud thoroughly mixed, so that any selec-
tion from it will represent a fair average
of the entire invoice. Then an examina-
! ton of the color is made by comparing a
sample with the so-called "Dutch Stand
ard" This latter consists of series of
sealed bottles containing sugars whose
value in crystallizable sugar has previously
been determined, the lighter colors
naturally representing the purer qualities.
/ If the sample is not above No. 13 in
color, it is again packed in tin box, a
duplicate of which is retained in the
examination room properly numbered,
! and then it is sent to the laboratory.
We may say in this connection that
?
stautly employed testing sugar at the APP
praiser's Stores in New York, and also,
more than this, that each of the large
ports of the country-Boston, Philadel-
phia, New Orleans, San Francisco and
! others-have their laboratories where
men are kept busy at this work.
The first operation that the sugar un-
dergoes is that of crushing and mixing
in mortar. This step is considered
necessary in order to remove any Jumps
or inequalities that may have been over
looked in the examination room, and to
make the mass more thoroughly homo
geneous. Then a suitable portion is
weighed out, the amount depending upon
the kind of polariscope employed. In
the United States laboratories the Scheib-
Ter modification of the polariscope is
used, and 1902 grams of substance is
the quantity taken for examination.
The weighed sugar is carefully washed
into a graduated flask holding exactly
fifty cubic centimeters, brought into a
solution by agitation, slight quantity
of lead acetate or sugar of lead is added,
and the mixture is filtered. The lead
salt is used for the purpose of partially
decolorizing the compound. The yellow
solution thus obtained is poured into the
polariscope tube and an examination or
reading is made. All sugars possess the
peculiar power of twisting or rotat-
ing ray of polarized light, either
to the right or left. Thus cane
sugar has a polarization to the right
of 73 deg. 8 min, grape sugar to the
right 81 deg. 4 min. Fruit sugar to the
left LOG deg, and so on. This charac-
teristic property of sugars is made use of,
and an instrument has been so con-
struoted that a ray of light entering the
apparatus becomes polarzed, then pass
ing through the tube containing the sac
charne solution is rotated in a definite
direction, and by means of suitable adj
justment this degree or amount of rota-
tion is shown on a readable scale attached
10 the instrument. The reading of the
vernier, as the scale is called, completes
the examination; in other words, the re-
suit obtained tells us exactly how much
pure crystallizable cane sugar is contained
in the sample. The percentage of pure
sugar is transmitted to the appraiser, who
then adjusts the amount of duty to be