IMPROVEMENTS IN THE MANUFACTURE OF LOAF SUGAR, AND IN THE MACHINERY OR APPARATUS EMPLOYED THEREIN
Year: 1872

page_text: LETTERS PATENT to Edward Thomas Hughes, of the Firm of Hughes
and Son, Patent Agents, 123, Chancery Lane, London, for the
Invention of "IMPROVEMENTS IN THE MANUFACTURE OF LOAF SUGAR, AND
IN THE MACHINERY OR APPARATUS EMPLOYED THEREIN." -A communication
from abroad by Eugen Langen, of Cologne.
Sealed the 14th February 1873, and dated the 17th August 1872.
PROVISIONAL SPECIFICATION left by the said Edward Thomas Hughes
at the Office of the Commissioners of Patents, with his Petition, on
the 17th August 1872.
I, EDWARD THOMAS HUGHES, of the Firm of Hughes and Son, Patent
Agents, 123, Chancery Lane, London, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN THE MANUFACTURE OF LOAF SUGAR,
AND IN THE MACHINERY OR APPARATUS EMPLOYED THEREIN," a communication to
me from abroad by Eugen Langen, of Cologne, to be as follows :—
The sugar solution evaporated to its proper consistency is put in
moulds formed as segments of a cylindrical ring, and the cylindrical face
of each mould consists of a movable bottom, which is removed after the

page_text: congelation. The bottom is fastened during the filling and congealing
operations by a slip bolt under the frame of the mould, and kept tight
by means of a sheet of india-rubber placed between the bottom and the
frame, and each mould is provided with a handle.
When the congelation is effected eight or other number of moulds are
placed in a centrifugal machine specially constructed to receive them,
the machine differing from others by the revolving chamber having no
top plate, and connecting the outer perforated sieve or cylinder to the
nave or boss by strong stays; but before the moulds are placed in the
machine the bottom plates with their india-rubber packings are removed,
and this can be readily effected where india-rubber is used, but would
not be possible without it, as no air could enter between the bottom
plate and the congealed mass, and the open moulds are put in the
chamber with their handles at the top, each mould occupying a space
between the perforated cylinder and two sets of the stays. As soon as
the machine is set in motion, the mould frames with their contents aro
pressed towards the sieve, and the syrup is quickly removed through the
fine passages between the sugar crystals, for after from ten to fifteen
minutes all the green syrup is forced out.
The next operation consists in clearing the crystals of their yellow-
brown colour, and this is effected by filling the interstices by claying
liquor in the following manner:-The centrifugal machine is stopped
when all the green syrup is removed and the eight moulds with their
loaves of sugar taken out, and then the bottom sides of the moulds are
again closed by the bottom plates and india-rubber packings. The
moulds are now placed in a vessel half filled with claying liquor, that is,
liquor saturate with a solution of refined sugar, and hermetically at the
top, and as the capillary attraction between the crystals is not sufficient
to draw the liquor, on account of the interstices being filled with air,
there is an exhausting or pneumatic machine connected by pipes to the
vessel, in order to make a vacuum and draw off the air from the crystals,
and then fresh air is let into the vessel to assist the capillary attraction,
so that all the interstices which were filled first with green syrup, and
afterwards with air, can be filled with the claying liquor, and as the
mould is closed by the plate and packing, the liquor can only enter at
the opposite side, and therefore the cover of syrup is driven towards the
closed side, which was the bottom of the mould when the evaporated
sugar solution was passed into it.

page_text: The object of forcing the thin coating of syrup to the closed side is to
enable it to be entirely carried off by the succeeding operation, for if
both sides of the congealed block or loaf were open the syrup would be
forced into the middle.
For forcing out the claying liquor and remaining syrup, the moulds,
after their closing plates and packings are removed, are placed in another
centrifugal machine, so that when the machine is set on the syrup and
liquor passes through the sieve or perforated cylinder, and thus the liquor
and syrup is diminished to a minimúm.
In the congealed solutions from sugar beet, or in those having very
small crystals, it may be necessary to repeat the claying operations; but
even in this case the entire operations only occupy about an hour. The
sugar produced, when white and almost dry, and for finishing the sugar,
it is only necessary to submit it to the operation of drying room for
from one to two days..
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Edward Thomas Hughes in the Great Seal Patent.
Office on the 17th February 1878.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
THOMAS HUGHES, of the Firm of Hughes and Son, Patent Agents,
123, Chancery Lane, London, send greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventeenth day of August, in the year
of our Lord One thousand eight hundred and seventy-two, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors, give
and graut unto me, the said Edward Thomas Hughes, Her special licence
that I, the said Edward Thomas Hughes, my executors, administrators,
and assigns, or such others as I, the said Edward Thomas Hughes, my
executors, 'administrators, and assigns, should at any time agree with,
and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, usc, excrcise;
and vend, within the United Kingdom of: Great Britain, and Ireland;
the Channel Islands, and Isle of Man, an Invention for "IMPROVE-
MENTS IN-
N-THE MANUFACTURE OF LOAF SUGAB, AND IN THE MACHINERY OR
..

page_text: APPARATUS EMPLOYED THEREIN," a communicatlon to mo from abroad by
Eugen Langen, of Cologne, upon the condition (amongst others) that I,
tlio said Edward Thomas Hughes, my executors or administrators, by
an instrument in writing under my, or their, or one of their hands and
seals, should particularly describe and ascertain the nature of the said 5
Invention, and in what manner the same was to be performed, and cause
the same to be filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Edward Thomas Hughes, do hereby
declare the nature of the said Invention, and in what manner the same 1
is to be performed, to be particularly described and ascertained in and
by the following statement (that is to say) :-
Before describing the improvements it may be as well to explain
briefly the branch of the manufacture to which they belong, at the same
time remarking that for a long time no essential progress has been made 1
in that branch.
5
The improvements are comprised in that part of the manufacture
which is situated between the evaporation of the refined filtered juice,
and the result of the whole product is a hard and consistent form (that
is loaf sugar). It is known that by the evaporation of the water con- 2
taining the sugar in solution, the filtered solution of coarse sugar is
transformed into a stiff pulp, which consists of crystals formed by the
evaporation and saturated sugar solution, and according to the old
method the evaporated mass is placed in moulds, where it slowly cools
and congeals into a hard lump. The mass is called filling mass, and the 2
saturated sugar solution which encloses the crystals filling up the spaco
between is called syrup.

page_text: syrup is pretty fast, but the speed diminishes more and more, and stops
before the capillary canals are entirely empty, the height at which it
remains depending on the nature of the filling mass, and the fineness of
the sugar crystals enclosed in syrup, and it often happens that after too
5 quick evaporation nothing at all drops out, and then the filling mass has
to be dissolved, and the mould filled again. When no syrup drops out
it is in consequence of the capillary attraction of the canals being
stronger than the gravity of the syrup; and it was to obviate this
phenomenon which frequently occurs in sugar refining that led to the
) present Invention.
"
P.
་
It is known that coarse sugar is yellow, and that its solution can be
.cleared or whitened by animal charcoal, but in the boiling process the
colour again. becomes 'dark, and the crystals contained in the filled.
mould, after the dropping out of the syrup, have the same color as the
coarse sugar, but this coloration does not penetrate the crystals, but is
caused by their being covered with syrup, and the crystals cannot be
made white except by washing, which is effected in the following
manner:-.
'
After the syrup has sunk down as near as possible to the point a
O portion of the upper part of the mass is cut off, then crumbled and
sifted, and again put into the mould, after which a saturated solution of
white refined sugar is poured in and is diffused amongst the contents of
the filled mould, and drives away the cover of syrup. This work, which
is called the claying operation, occupies from six to eight, days, and at
3 the same time the liquor requires a great quantity of the best white
coarse or refined sugar.
I
After six or eight days fresh liquor is added, and the contents become"
white; but the lower part of the mould before filled with syrup is now.
filled with liquor, which can only be removed by a suction apparatus,
b after which the sifted sugar is removed, and the humid loaf taken out of
the mould. The loaf is now transported to the drying room, where it
must also remain for eight or ten days, and this ancient mode of manu-
facture has been continued notwithstanding the many inconveniences
connected with it, such as,―
First. The mixture of a large quantity of white sugar solution with

page_text: which is in contact with the air.
Thirdly. The necessity of having very large rooms, and a very large
number of filling moulds.
Fourthly. The loss of interest caused by the number of days occupied !
from the filling operation to the completion of the drying.
And, fifthly. The only result of this tedious proceeding is a piece of
white solid sugar formed as a loaf, which is very unpractical both for
packing and trade.
The desire to pursue a better method has existed for a long time, and 1
since centrifugal machines were invented attempts have been made to
employ them, and in the first case the ordinary filled moulds were placed
in the apparatus, but that plan was soon given up.
When the mould was placed in the centrifugal machine in order that
the syrup should be swung or forced out, the said syrup was driven 1
radially to the exterior of the mould without affecting the middle of the
loaf, and thus there was always a kernel of yellow dirty sugar, and the
proceedings caused many fatal accidents, because the centrifugal
machines were required to bo of very large dimensions, and the weak
wall of sugar could not always resist the centrifugal force.
Since these experiments no attempts have been made to manufacture
white loaf sugar as an immediate product in the centrifugal machine,
although it has been often used in the manufacture of sugar in its
moist or crumbled state. Such sugar placed in a moist state in the
centrifugal machine can be pressed as plates, but these sugar plates,
when dried, had not the solidity of refined loaf sugar, and this plan was
given up.
The method lately described by Mr. Weinrich Schröder approaches
the solution of the problem, but does not solve it. The method was to
clay by steam in order to cause the sugar mass to fall to pieces, but
when the pieces were pressed by the centrifugal force towards the sieve
of the machine the pieces became crumbled, as they had no cohesive
form.
Clayings by means of steam or water dissolves a quantity of the
filling mass, but if the sugar is to be clarified in the centrifuval machine

page_text: it is only possible by a saturated sugar solution. The claying liquor if
used, should be added in the centrifugal machine; but this is not pos-
sible in the method described by Weinrich Schröder, because the claying
liquor, instead of passing through the sugar, prefers the way between
the pieces of sugar.
The application of claying liquor in the centrifugal machine has
always the disadvantage that the liquor ascends the interior sugar sur-
face, stops up the small holes, and goes rapidly towards the sieve, so
that the sugar pieces are scarcely touched by the claying liquor, and
remain as yellow pieces in the mass, and even a very great quantity of
claying liquor cannot overcome this inconvenienco.
The description of the foregoing modes of manufacturing sugar is for
the purpose of explaining the causes which led to the present Invention,
and to enable its value to be fully perceived, and the following is a
description of the improvements in the manufacture of loaf sugar, and in
the machinery or apparatus employed therein, reference being had to
the Figures on the accompanying Sheet of Drawings, and to the letters
of reference marked thereon.
The sugar solution, evaporated to its proper consistency, is put into
moulds which are swung round by the centrifugal machine, the moulds
being formed as segments, Figs. A and B, of a segmental ring, and the
cylindrical face of each mould consists of a moveable bottom, which is
removed after the congelation of the filled mass, after which a number
of these moulds, say, eight, are placed in the centrifugal machine. The
moveable bottom plate is fastened, during the filling, and congealing
operations, by a slip bolt under the frame of the mould, and a packing of
sheet caoutchouc is placed between the frame and bottom plate. When
the congelation of the mass is effected, the filled moulds, which have
handles, are placed in a centrifugal machine specially constructed to
receive them. This machine, Figs: 1, 2, and 3, differs from others by
the revolving chamber, Figs. O and D, having no top plate or-sur-
mounting edge, and that the sheet iron cylinder bored as a sieve has
eight strong stays connected to it, and the nave or boss to which the
shaft of the cylinder is keyed or fastened, and these stays divide the
chamber into eight compartments or divisions. The construction is
therefore so solid and strong that a great weight can be placed in the
machine, and thereby under this method practicable.

page_text: The filled moulds destined to be placed in the machine are treated in
the following manner:-First, the moveable bottom plates with their
caoutchouc packings are removed, and it may be here remarked that the
sheet of caoutchouc is absolutely necessary, because it packs the mould,
and also that without it the iron bottom could not be removed because {
no air could enter between the bottom and the congealed mass. The
opened moulds are now placed with their handles at the top in the
chamber of the centrifugal machine, Fig. 1, and each mould fills the
space formed by the sieve plate and two stays. As soon as the centrifugal
machine is set in motion, the frames with their contents rounded at the
outside are pressed towards the sieve, and the syrup is quickly removed
through the fine passages or canals between the sugar crystals. The
small sugar crystals aro cleared radially, the iron frame enclosing them
preventing their displacement, and after from ten to fifteen minutes have
clapsed all the green syrup is swung or forced out.
The next operation consists in clearing the filled mass of the yellow
brown color, and this is effected by filling the interstices formed by
swinging out the syrup with claying liquor in the following manner :—The
centrifugal machine is stopped when all the green syrup is removed and the
eight moulds with their lumps of sugar taken out, and then the bottoms
of the moulds are again closed by the iron plates and caoutchouc
packings. The moulds are now placed in a vessel, Fig. 4, half filled
with claying liquor, but as by simple capillary attraction the liquor
could not sufficiently enter the interstices because they are filled with
air, it is evident this air must be removed, and for this purpose the top
of the vessel is turned true and hermetically sealed with a cover. An
exhausting or pneumatic machine is now connected to the vessel at the
valve a by a conduit of pipes, in order to make a vacuum and draw off
the air from the crystals, and after the valve a is closed, fresh air is let
into the vessel through the valve 6 to assist the capillary attraction, so
that all the interstices which were first filled with green syrup and
afterwards with air can be filled with the claying liquor. The curved
exterior side being closed, the liquor can only enter on the contrary side,
and the cover of syrup is driven towards the exterior side, and this fact
is very important, because if the exterior side was not closed the claying,
liquor could enter on that side and pass towards the middle; but if the
impregnation is made from the inner or open side, any green syrup
which was left must, at the second working of the centrifugal machine,

page_text: be instantly removed through the sieve, and the whole remaining liquor
can drive out the yellow syrup, and wash the small crystals.
For forcing out the remaining syrup and claying liquor, the moulds,
after, their closing plates and packings are removed, are placed in another
centrifugal machine, Fig. 2, and therefore the mixture of claying liquor
and
syrup
is diminished to a minimum.
In the congealed solutions or filling masses having fine small crystals,
or when the solutions are less pure, as for example, the evaporated
liquors from beet sugar, they cannot be rendered white enough by one
claying operation, and therefore this operation is repeated in another
vessel, Fig. 5, and the liquor afterwards removed in another centrifugal
machine, Fig. 3.
"
When there are two claying operations, the liquor resulting from the
centrifugal machine, Fig. 3, is used as the first claying liquor in Fig. 4,
and it is only in Fig. 5 that a fresh claying liquor is employed; but even
in this case the entire operations only occupy about an hour, the result
being the production of a solid white piece of sugar, almost dry, and of
a much more practical shape than the ordinary sugar loaf, and to finish
this sugar it is only necessary to submit it to the drying operation in the
drying room for from one to two days.
From the foregoing description of the improvements it will be scen
that there is great economy of time and interest on capital, a minimum
number of moulds, and the capability of using comparatively small
rooms and factories; other advantages consist,-
First. In the employment of a centrifugal machine of such stability as
to prevent accident.
Secondly. The saving of 75 per cent. of white sugar used in the
claying liquor.
Thirdly. The reduction of the mixture of claying liquor and syrup to
a minimum.
Fourthly. The diminution of the decomposition and acidification of
the sugar, which is unavoidable in the old method where so much time
is occupied.
And, fifthly. The capability of acting on congealed or evaporated
solutions of a lower quality than is possible by the old method, and also

page_text: the capability of the direct transformation of beet sugar juice into
refined sugar.
In witness whercof, I, the said Edward Thomas Hughes, have here-
unto set my hand and seal, this Seventeenth day of February,
in the year of our Lord One thousand eight hundred and seventy-
three

page_text: In the Matter of Letters Patent granted to EDWARD THOMAS HUGHES, of
the Firm of Hughes and Son, Patent Agents, 123, Chancery Lanc,
London, for the Invention of "IMPROVEMENTS IN THE MANUFACTURE
OF LOAF SUGAR, AND IN THE MACHINERY OR APPARATUS EMPLOYED
THEREIN." A communication from abroad by Eugen Langen, of Cologne,
bearing date at Westminster, the Seventeenth day of August, One thousand
eight hundred and seventy-two, No. 2456.
eight hundred and seventy-two, No. 2456.
DISCLAIMER AND MEMORANDUM OF ALTERATION as proposed to be
entered by Eugen Langen, of Cologne, in the German Empire, Assignee of the
said Letters Patent, pursuant to the Statutes in that case made and
provided.
WHEREAS Her Majesty Queen Victoria by Her Letters Patent under the Great
Seal of the United Kingdom of Great Britain and Ireland, bearing date at
Westminster, the Seventeenth day of August 1872, in the thirty-sixth year of Her
reign, did give and grant unto the said Edward Thomas Hughes, his executors,
administrators, and assigns, the sole privilege for the term of fourteen years thence
next ensuing, of making, using, exercising, and vending within the United Kingdom
of Great Britain and Ireland, the Channel Islands, and Isle of Man, the said
Invention of IMPROVEMENTS IN THE Manufacture of Loaf SuGAR AND IN THE
MACHINERY OR APPARATUS EMPLOYED THEREIN." A communication from abroad
Et
by Eugen Langen, of Cologne:
And whereas, in pursuance of a proviso in the said Letters Patent contained, the
said Edward Thomas Hughes did, within six calendar months next after the date
of the said Letters Patent, cause a Specification or Instrument in writing under
his hand and seal, purporting to describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, to be duly filed in the
Great Seal Patent Office :

page_text: "
And whereas the said Letters Patent have been assigned to, and became and now
are vested in me the said Eugen Langen:
And whereas since the filing of the said Specification, I, the said Eugen Langen,
have ascertained that the said Specification may be objected to on the ground that
it does not define with sufficient precision the Invention intended to be claimed
under the said Letters Patent, and that consequently it may be understood to claim
more than was or is intended to be claimed thereby, and whereas there are in the
said Specification certain clerical errors which it is desirable to have corrected, in
consequence thereof I hereby disclaim and alter parts of the said Specification in
manner following, that is to say :-
"
ย
"
"
"
"
Referring to the Queen's Printers Copy of tho said Specification; at page 4,
line 19, for "is" I substitute "in;" at page 4, line 23, before the word "saturated
I insert "of;" at page 5, line 2, for "height" I substitute" point;" at page 5,
line 19, after "point" I insert "of the mould;" at page 6, line 23, for "it" I sub-
stitute that machine;" at page 6, line 28, for "Mr." I substituto "Messrs. ;" and
between Weinrich and "Schröder" I insert "and;" at page 6, line 33, for
form" I substitute "character;" at page 6, line 34, for "Clayings" I substitute
Claying;" at page 7, line 3, I insert "and" between "Weinrich" and "Schröder;"
at page 7, line 30, I omit "Figs. 1, 2, and 3;" at page 7, line 31, I omit "Figs.;'
at page 7, line 33, between "and" and "the" I insert "to;" and for "to," after
"boss," I substitute "in;" at page 7, line 37, I omit "and;" and for "under" I
substitute "rendering ; ;" at page 8, line 8, for "Fig. 1 " I substitute "C;" at page 8,
line 20, after "sugar" I insert "arc;" at page 8, line 22, for "Fig. 4" I substitute
"IV.;" at page 9, line 5, for "Fig. 2" I substitute "1I. ;" and for "therefore"
I substitute "thus;" at page 9, line 7, I omit "In;' at page 9, line 9, I
omit "they" at page 9, line 11, for "Fig. 5" I substitute "V.;" at page
9, lino 12, for 66
'Fig. 3" I substitute "III.;" at page 9, line 14, I insert
"second" before "centrifugal;" and I omit "Fig. 3," and "in Fig. 4," at page 9,
line 15, for "in Fig. 5" I substitute "for the second claying;" at page 10, after
line 2, I insert the following paragraph :—“ Having thus described the nature of 3
my Invention, and in what manner the same is to be performed, I would have it
"understood that I make no general claim to the use of centrifugal machines for
cleansing or claying sugar, nor to any parts of the herein-described apparatus and
process other than the moulds made of a shape to suit the circular form of the
"centrifugal machine, and provided with removeable bottoms, and charging the 3
sugar with claying liquor by placing the moulds along with the liquor in close
vessels, extracting the air, and then adinitting air to force the liquor into the
vacuous interstices of the sugar." And the said Specification when disclaimed,
altered, and amended, will read as follows: -
"
"
TO ALL TO WHOM THESE PRESENTS SHALL COME, 1, EDWARD THOMAS
HUGUES of the kirm of Hughes and Son Patent Acenta 122 Chancery Lane

page_text: under my, or their, or one of their hands and seals, should particularly described and
ascertain the nature of the said Invention, and in what manner the same was to
be performed, and cause the same to be filed in the Great Seal Patent Office within
six calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Edward Thomas Hughes, do hereby declare
the nature of the said Invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement
(that is to say):-
Before describing the improvements it may be as well to explain briefly the
branch of the manufacture to which they belong, at the same time remarking that
for a long time no essential progress has been made in that branch.
The improvements are comprised in that part of the manufacture which is
situated between the evaporation of the refined filtered juice, and the result of the
whole product in a hard and consistent form (that is, loaf sugar). It is known that,
by the evaporation of the water containing the sugar in solution, the filtered
solution of coarse sugar is transformed into a stiff pulp, which consists of crystals
formed by the evaporation and of saturated sugar solution; and, according to the
old method, the evaporated mass is placed in moulds, where it slowly cools and
congeals into a hard lump. The mass is called filling mass, and the saturated
sugar solution which encloses the crystals filling up the space between is called
Бутир.
By a repeated crystallization of the syrup the mother lie becomes more and more
exhausted of crystallizable sugar, and finally becomes the syrup of commerce.
The sugar mould, which formerly consisted of earthenware, but is now made of
sheet iron, has a holo at its point or apex, which, during the filling operation, is
closed by an enveloped nail. The filled mould, when cold, is transported to the
upper floor of the building, and the nail withdrawn; and some days are allowed for
the syrup to drop out through the hole at the apex or bottom. At the commence-
ment the trickling of the syrup is pretty fast, but the speed diminishes more and
more, and stops before the capillary canals are entirely empty, the point at which it
remains depending on the nature of the filling mass and the fineness of the sugar
crystals enclosed in syrup, and it often happens that after too quick evaporation
nothing at all drops out, and then the filling mass has to be dissolved and the mould
filled again.
When no syrup drops out it is in consequence of the capillary attraction of the
canals being stronger than the gravity of the syrup; and it was to obviate this
phenomenon, which frequently occurs in sugar refining, that led to the present
Invention.
:
It is known that coarse sugar is yellow, and that its solution can be cleared or
whitened by animal charcoal, but in the boiling process the colour again becomes
dark, and the crystals contained in the filled mould after dropping out of the syrup
have the same colour as the coarse sugar; but this coloration does not penetrate the
crystals, but is caused by their being covered with syrup, and the crystals cannot
be made white except by washing, which is effected in the following manner:-
After the syrup has sunk down as near as possible to the point of the mould, a
portion of the upper part of the mass is cut off, then crumbled and sifted, and
again put into the mould; after which a saturated solution of white refined sugar
is poured in, and is diffused amongst the contents of the filled mould, and drives
away the cover of syrup. This work, which is called the claying operation, occupies
from six to eight days, and at the same time the liquor requires a great quantity of
the best white, coarse, or refined sugar.
After six or eight days, fresh liquor is added, and the contents become white; but
the lower part of the mould, before filled with syrup, is now filled with liquor, which
can only be removed by a suction apparatus, after which tho sifted sugar is removed,
and the humid loaf taken out of the mould. The loaf is now transported to the
drying room, where it must also remain for eight or ten days; and this ancient mode

page_text: of manufacture has been continued, notwithstanding the many inconveniences connec-
ted with it, such as,―
First. The mixture of a large quantity of white sugar solution with yellow syrup.
Secondly. The decomposition and acidity of that portion of the sugar which is in
contact with the air.
Thirdly. The necessity of having very large rooms and a very large number of
filling moulds.
Fourthly. The loss of interest caused by the number of days occupied from the
filling operation to the completion of the drying.
And, Fifthly. The only result of this tedious proceeding is a piece of white solid
sugar formed as a loaf, which is very unpractical both for packing and trade.
The desire to pursue a better method has existed for a long time, and since cen-
trifugal machines were invented, attempts have been made to employ them, and in
the first case the ordinary filled moulds were placed in the apparatus, but that plan
was soon given up.
When the mould was placed in the centrifugal machine, in order that the syrup
should be swung or forced out, the said syrup was given driven radially to the exterior
of the mould without affecting the middle of the loaf, and thus there was always a
kernal of yellow dirty sugar, and the proceedings caused many fatal accidents,
because the centrifugal machines were required to be of very large dimensions, and
the weak wall of sugar could not always resist the centrifugal force.
Since these experiments, no attempts have been made to manufacture white loaf
sugar as an immediate product in the centrifugal machine, although that machine
has been often used in the manufacture of sugar in its moist or crumbled state.
Such sugar placed in a moist state in the centrifugal machine can be pressed as
plates, but these sugar plates when dried had not the solidity of refined loaf sugar,
and this plan was given up.
The method lately described by Messrs. Weinrich and Schröder, approaches the
solution of the problem, but does not solve it. The method was to clay by steam in
order to cause the sugar mass to fall to pieces, but when the pieces where pressed
by the centrifugal force towards the sieve of the machine, the pieces became crumbled
as they had no cohesive character.
Claying, by means of steam or water, dissolves a quantity of the filling mass,
but if the sugar is to be clarified in the centrifugal machine it is only possiblo by a
saturated sugar solution.
The claying liquor, if used, should be added in the centrifugal machine, but this
is not possible in the method described by Weinrich and Schröder, because the
claying liquor, instead of passing through the sugar, prefers the way between the
pieces of sugar.
The application of claying liquor in the centrifugal machine has always the dis-
advantage that the liquor ascends the interior sugar surface, stops up the small
holes, and goes rapidly towards the sieve, so that the sugar piecos are scarcely
touched by the claying liquor, and remain as yellow pieces in the mass, and even a
very great quantity of claying liquor cannot overcomo this inconvenience.
The description of the foregoing modes of manufacturing sugar is for the purpose
of explaining the causes which led to the present Invention, and to enable its value
to be fully perceived; and the following is a description of the improvements in
the manufacture of loaf sugar, and in the machinery or apparatus employed therein,
reference being had to the Figures on the accompanying Sheet of Drawings, and to
the letters of reference marked thereon.
The sugar solution evaporated to its proper consistency is put into moulds,
which are swung round by the centrifugal machine, the moulds being formed as
segments, Figs. A and B, of a segmental ring; and the cylindrical face of each
mould consists of a moveable bottom, which is removed after the congealation of the
filled mass, after which a number of these moulds, say eight, are placed in the
centrifugal machine. The moveable bottom plate is fastened during the filling and
congealing operations by a slip bolt under the frame of the mould, and a packing

page_text: of sheet caoutchouc is placed between the frame and bottom plate. When the
congelation of the mass is effected, the filled moulds, which have handles, are placed
in a centrifugal machine specially constructed to receive them. This machine:
differs from others by the revolving chamber C and D having no top plate or sur-
mounting edge, and that the sheet-iron cylinder bored as a sieve has eight strong
stays connected to it, and to the nave or boss in which the shaft of the cylinder is
keyed or fastened, and these stays divide the chamber into eight compartments or
divisions. The construction is therefore so solid and strong that a great weight
can be placed in the machine, thereby rendering this method practicable.
The filled moulds destined to be placed in the machine are treated in the following
manner:
First. The moveable bottom plates with their caoutchouc packings are removed, and
it may be here remarked that the sheet of caoutchouc is absolutely necessary,
because it packs the mould, and also that without it the iron bottom could not be
removed, because no air could enter between the bottom and the congealed mass.
The opened moulds are now placed with their handles at the top in the chamber of
the centrifugal machine C, and each mould fills the space formed by the sieve plate
and two stays. As soon as the centrifugal machine is set in motion the frames with
their contents rounded at their outside are pressed towards the seive, and the syrup is
quickly removed through the fine passages or canals between the sugar crystals.
The small sugar crystals are cleared radially, the iron frame enclosing them preventing
their displacement, and after from ten to fifteen minutes have elapsed all the groen
syrup is swung or forced out.
The next operation consists in clearing the filled mass of the yellow brown color,
and this is effected by filling the interstices formed by swinging out the syrup with
claying liquor in the following manner:-The centrifugal machine is stopped when
all the green syrup is removed, and the eight moulds with their lumps of sugar are
taken out, and then the bottoms of the moulds are again closed by the iron plates
and caoutchouc packings. The moulds are now placed in a vessel IV., half filled
with claying liquor, but as by simple capillary attraction the liquor could not
sufficiently enter the interstices because they are filled with air, it is evident this air
must be removed, and for this purpose the top of the vessel is turned true and
hermetically sealed with a cover; an exhausting or pneumatic machine is now
connected to the vessel at the valve a by a conduit of pipes, in order to make a
vacuum and draw off the air from the crystals, and after the valve a is closed fresh
air is let into the vessel through the valve b to assist the capillary attraction, so
that all the insterstices which were first filled with green syrup and afterwards
with air can be filled with the claying liquor. The curved exterior side being
closed, the liquor can only enter on the contrary side, and the cover of the syrup
driven towards the exterior side, and this fact is very important, because if the
exterior side was not closed the claying liquor could enter on that side and pass
towards the middle; but if the impregnation is made from the inner or or open side,
any green syrup which was left must at the second working of the centrifugal
machine be instantly removed through the sieve, and the whole remaining liquor
can drive out the yellow syrup and wash the sinall crystals.
For forcing out the remaining syrup and claying liquor, the moulds after
their closing plates and packings are removed are placed in another centrifugal
machine II., and thus the mixture of claying liquor and syrup is diminished to a
minimum.
The congealed solutions or filling masses having fine small crystals; or when the
solutions are less pure, as for example, the evaporated liquors from beet, sugar cannot
be rendered white enough by one claying operation, and therefore this operation
is repeated in another vessel V., and the liquor afterwards removed in another
centrifugal machine III.
When there are two claying operations, the liquor resulting from the second
centrifugal machine is used as the first claying liquor, and it is only for the second
claying that a fresh claying liquor is employed; but even in this case the entire

page_text: operations only occupy about an hour, the result being the production of a solid white
picce of sugar, almost dry, and of a much more practical shape than the ordinary
sugar loaf, and to finish this sugar it is only necessary to submit it to the drying
operation in the drying room for from one to two days.
From the foregoing description of the improvements it will be seen that there is a
great economy of time and interest on capital, a minimum number of moulds, and
the capability of using comparatively small rooms and factories.
Other advantages consist,-
First. In the employment of a centrifugal machine of such stability as to prevent
accident.
Secondly. The saving of 75 per cent. of white sugar used in the claying
liquor.
Thirdly. The reduction of the mixture of claying liquor and syrup to a
minimum.
Fourthly. The diminution of the decomposition and acidification of the sugar,
which is unavoidable in the old method, where so much time is occupied.
And, Fifthly. The capability of acting on congealed or evaporated solutions of a
lower quality than is possible by the old method, and also the capability of the
direct transformation of beet sugar juice into refined sugar.
Having thus described the nature of my Invention and in what manner the same
is to be performed, I would have it understood that I make no general claim to the
use of centrifugal machines for clensing or claying sugar, nor to any parts of the
herein-described apparatus and process, other than the moulds made of a shape to
suit the circular form of the centrifugal machine, and provided with removeable
bottoms, and charging the sugar with claying liquor by placing the moulds along
with the liquor in close vessels, extracting the air, and then admitting air to force
the liquor into the vacuous interstices of the sugar.
In witness whereof, I, the said Edward Thomas Hughes, have hereunto set my
hand and seal, this Seventeenth day of February, in year of our Lord One
thousand eight hundred and seventy-three.
E. T. HUGHES. (L.S.)
In witness whereof, I, the said Eugen Langen, have hereunto set my hand and
soal this Fourteenth day of June. in the year of our Lord One thousand
Witness,
CHA³. D. ABEL,
20, Southampton Buildings.
EUGEN LANGEN. (L.S.)
HARDINGE CIFFARD,
Solictor-General.