, 1874-05-27
q G Ar TIE 5 I S

For many years past, it has been the custom
to grade sugars at the United States Custom
Houses according to the Dutch standard elias
sihcati0n, which has reference only to color,
and consequently sugars have been dutiabIe
either higher or lower in accordance with the
color they displayed.
This system Of grading sugars has been
abandoned by the governments Of England,
Germany and France, because it was found
that the color was not q clear or genuine in
dication to the real value of the sugar, which
must necessarily depend upon the amount of
crystaIlizable sugar the raw material contains
and its relative freedom from extraneous sub
stances. All raw sugars contain q certain
percentage Of gummy matters, mineral salts
and moisture, together with such impurities
as may become mixed with it during the pro-
gress Of manufacture on the plantation. These
substances always exist to a greater or less
extent, and Of course have more to do with
the color eff the sugar than with its real crys-
tallizablo value. 1t is not to be supposed,
however, that the darkest sugar is the most
impure. A sugar which will be graded very
low, according to the Dutch standard, and
therefore paying a low rate of duty, may often
be much more valuable to the trade, owing
to the greater amount Of crystallizable matter
it will contain than O sugar of much better CO.
lor upon which a higher rate of duty has been
paid. Here then comes the difficulty, and it
NAV be said the absurdity of the use of the
Dutch standard classification, for it has refer
ence only to the color Of the sugars, without
regard to their real intrinsic values.
Notwithstanding the difficulties in the way
Of interfering with values, to which such a sys-
tenn puts both the importer and %reiner, the
Government still adheres to it, and consequent
" the duties collected upon sugars are for
the most part fictitious.
The trade, however, realizes the value of
knowing exactly what the raw material is
worth and to ascertain this recourse is had
to chemical analysis, by which the orystalliza-
BILE value of the sugar can be established beyond
a doubt. The chief test employed is that of
polarization; and by the application of this
principle a correct knowledge may be had of
the exact amount of the crystallizable sugar
contained in the raw material. These tests
are conducted by experienced analytical chem
lists, notably Me8srs. KrackoWltzer q Harnish,
who gave certificates of results obtained from
samples furnished, upon which purchases and
sales are made.
In reference to this matter of polarization,
Mr.. Harnish informed a BULLETIN reporter
that it was productive of the most singular
results, which showed substantially that the
natural colors Of raw sugar were no possible
indications of their values, He explained the
matter fully, and illustrated his remarks by
showing a sample of MuscoVado Porto Rico
sugar rated No. IS by the Dutch Standard,
which p~olarized at only IS per cent. and as a
contrast he next showed a dark centrifugal
sugar rated No. s Dutch standard, which
polarized at 90 per cent or nearly ten per cent.
higher, and consequently the most valuable.
The Muscovado was, of course, much high
er in color, and probably paid a higher rate
of duty, but it was in reality worth less than
the dark centrifugal. To arrive at these
valuable results an instrument called a polar
imeter or polarisoope is used, by which a ray
of polarized light can be thrown upon a sub
stance held in solution, and thus the amount