FOR THE REFINING OF SUGAR, AND THE MAKING OF SUGAR FROM THE CANE JUICE, AND BY MEANS OF WHICH MUSCAVADO OR BROWN SUGAR MAY BE MADE TO YIELD A CONSIDERABLY GREATER PROPORTION OF REFINED SUGAR, AND BETTER IN QUALITY, THAN CAN BE OBTAINED BY THE METHOD USUALLY PRACTISED
Year: 1784

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
MURRAY, of Lower Grosvenor Place, in the Parish of Saint George, Hanover
Square, in the County of Middlesex, Esquire, send greeting.
WHEREAS His most Excellent Majesty King George the Third, by
His Letters Patent under the Great Seal of Great Britain, bearing date
the Twentieth day of August, in the twenty-fourth year of His reign, did give
unto me, the said Robert Murray, His special licence that I, the said Robert
Murray, during the term of fourteen years therein expressed, should and
lawfully might make, usc, exercise, and vend, within England, Wales, and
Town of Berwick-upon-Tweed, and within all His Majesty's Dominions and
Plantationis abroad, my discovery "FOR THE REFINING OF SUGAR, AND THE
MAKING OF SUGAR FROM THE CANE JUICE, AND BY MEANS OF WHICH MUSCAVADO OR
BROWN SUGAR MAY BE MADE TO YIELD A CONSIDERABLY GREATER PROPORTION OF
REFINED SUGAR, AND BETTER IN QUALITY, THAN CAN BE OBTAINED BY THE METHOD
USUALLY PRACTISED;" in which said Letters Patent there is contained a
proviso obliging me, the said Robert Murray, under my hand and seal, to
cause a particular description of the nature of my said Invention, and
how the same is to be performed, to be inrolled in His Majesty's High
Court of Chancery within four calendar months, next after the date of the
said recited Letters Patent, as in and by the same, relation being thereunto
had, may more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said provisoe, I, the said
Robert Murray, do hereby declare that my said Discovery for the Refining of
Sugar and the Making of Sugar from the Cane Juice, and by means of which
Muscavado or Brown Sugar may be made to yield a considerably greater
Proportion of Refined Sugar, and better in Quality, than can be obtained by
the Methods usually Practised, is described in the manner following (that is
to say):
purpose
The Improved Process of making Sugar from Cane Juice.-The juice from
the mills is immediately run through linen into two or three copper cauldrons,
hereafter described, and care is taken that the quantity in each cauldron be
such as fills it to twelve or thirteen inches only above the bottom, in which
situation it is quickly brought to a state of ebulition for the
of evapo-
rating a part of the water, and condensing and contracting the mass. While it is
boiling, a refuse matter presents itself on the surface as a black skum, which
must be removed with a skimmer. When it is contracted till the liquor is
become thick, and when by introducing the skimmer the latter drops which
fall therefrom form small sheets, you must empty your cauldrons, previously
putting out or suppressing the fires which were under them. The liquor in
this state is taken from the two or three cauldrons, and poured through a
strainer, hereafter described, into one or more cauldrons (called boilers, which
are filled about nine inches (leep); there it is again brought to a state of
ebulition, and the evaporation is continued until it be ready to chrystallize in
large distinct grains. When the mass is in this state you take it from the
boiler, having first covered or extinguished the fire, and put it into a cooler
(hereafter described), in which it is frequently stirred with a wooden spatula to
accelerate chrystallization, which will be compleated by this means in more or
less time according as the mass is poorer or richer. When the chrystallization
is compleat, you take the mass and place it in a draining trough (hereafter
lescribed), which is supported by two trestles. Under this trough is placed a
cooler, similar to the above-mentioned, and which serves as a recipient for the
syrup, which, oosing from the sugar and filtering itself through the apertures
at the bottom of the trough, falls into this recipient, leaving in the trough the
chrystallized mass, which must be left to drain well; you then put it into
hogsheads in which it is to be brought to Europe, when you mean to despatch
it as raw sugar. If you mean to clay it, then follow the process for purifica-
tion or claying of raw sugar, as described in the process of refining. The
syrup which has fallen into the recipient is again put into a cauldron called the
evaporating cauldron; there it is evaporated afresh and brought to the same
degree of consistence with the cane juice. When brought to this state it is

page_text: syrup
placed in a cooler, such as has been already mentioned, until it shall become
chrystallized; 'tis then put into a trough to drain, as has been already described.
The then seperates and precipitates itself as in the first process, and the
sugar, well drained, is removed into hogsheads. The syrup which has oozed
from this second process is again evaporated, and treated in every respect as
the former, until the mass is entirely exhausted of chrystalline particles.
N.B. If any animal syruph can be procured (and whites of eggs are preferable
to any other), an admixture thereof in the cauldron will assist in getting rid of
the extractive part, and render the raw sugar most beautiful.
:
The Cauldrons. They are all of copper, and of the same form. The bottom
which is flatt is from sixty to sixty-six inches diameter within. The bottom
ought to weigh from four hundred and eighty to five hundred pounds weight.
They must be hammered cold and well smooth'd; the greatest thickness must
be in the middle; the elevation to be only one sixth part of an inch thick.
The circumference of the cauldron must be made of three sheets of copper
nail'd to the bottom, and brazen'd together and soldered with strong solder.
The heigth of the first circumference is from sixteen to seventeen inches, and
cach sheet ought to weigh from fifty-five to sixty pounds; of course the three
sheets from one hundred and sixty-five to one hundred and eighty. pounds.
At seventeen inches from the bottom of the cauldron the sheets of copper. are
turned down horizontally about two inches, and raised again perpendicularly in
this form. On the border a second elevation of sixteen inches is to be joined,
but this last is discontinued, or wanting at the front of the cauldron, where an
aperture is left of four feet six inches to admit of a brace. The cauldron is
incircled with an iron hoop at the top. Each cauldron should be built on a
seperate furnace, and have its proper fire, whether its fuel is to be of trash,
wood, or coals. The whole circumference of the cauldrons ought to be built up,
as well as six inches of the bottom all round the edge of it, to the end that the
fire may be reduced to forty-eight or fifty-four inches, according to the diameter
of the cauldron, and that neither flame or heat shall circulate round the sides
of the cauldron, as the fire must only operate in its bottom. The front of the
furnace and all that surrounds the cauldron should be covered with lead.
The Coolers. These are made of wood, five feet square, with an elevation of
eight inches, and must be lined with sheets of a pure white metal, which is or
ought to be similar to Smith's Patent Metal; these sheets are soldered together,
or folded into grooves and turned down over the edges of the wooden case.
The Draining Troughs.-A trough of wood, four feet long, three feet wide,
and one foot high, at the bottom of which, lengthways, are three traverse

page_text: pieces of wood, exactly fitted to the trough. These ought to be of the form of
the amiss rail in the inside of the trough, round which, on a level with the
traverses, is an abutment projecting about an inch. On the traverses is placed
an osier hurdle, which forms the bottom of the trough, and is supported at the
extremities by the abutment. This bottom is not fixed, but may be removed
at pleasure.
The Strainer. These strainers are of woollen, fixed on the surface of a
wickerwork basket, in the form of an oblong square, by means of iron hooks,
through which the liquor is to be poured.
The Improved Process for Refining Raw Sugar.-The basis of this process,
and what essentially" distinguishes it from the one now pursued, is the
preliminary of washing the raw sugar. The refiners at present disolve
it in the state in which it arrives from the colonies. By this new process
it never is dissolved without being previously stripped of the substance which
discolours it. This substance is an oily matter which opposes the chrystalliza-
tion of a considerable portion of sugar, as well as robs it of its whiteness. To
seperate this matter the raw sugar is put into cases or boxes (hereafter
described) to the heigth of about eighteen inches; there, after having been
-well levelled without any manner of compression, it is covered with a white
clay, strongly triturated with water, and brought to the consistence of thick
pap; this, which is the first coat or covering, should be laid on about three
quarters of an inch thick.. When the water contained in this coat is infiltered
into the mass of sugar, the dry clay is removed from the surface, and a second
coat or covering of the same clay, about an inch thick, is applied. As soon as
the white clay begins to retreat and rack upon the surface, from one hundred
to one hundred and six degrees of heat by Fahrenheit's thermometer is intro-
duced into the warehouse; this heat gives a fluidity to the dissolution (caused
by the water) of that substance which colours the sugar. This dissolution
'infilters itself through the mass, and precipitates itself through the apertures at
the bottom of the case into a recipient placed before it (which recipient is
exactly the same as the coolers already described in the process for boiling the
cane juice, only that the coolers for refining are two inches larger in tho
square). The clay which remains on the sugar is taken off when dry, and the
heat is contained till the draining ceases. The purified or bleached sugar is
taken from the case, of which a greater or less quantity will be obtained,
according to the quality of the raw sugar. If it was good in quality, there
will remain only four or five inches not purified. These remains are collected
'to fill the cases afresh, of which near four fifths remain empty by the removal
of the purged sugar. When they are filled again, the process of claying is

page_text: performed precisely as above described. The drainings which are produced by
this purification furnish an abundant chrystalization in the recipient. This
chrystalization is spontaneous. When by.repeated purifications the recipient
becomes three quarters full, it is emptied into draining troughs (already
described in the process for raw sugars); all that which is chrystalized
remains in the trough; that which is not precipitates itself through the hurdle.
This a black, thick, and bitter melasses, and is no longer susceptible of
chrystalization. From it, however, we may extract, by means of fermentation,
a quantity of spirits fit for varnishing, but which is disagreeable to the palate
if drank. The raw sugar, clayed, purged, or purified by this process, is then
in a proper state to be refined. For this end it must be clarified. This opera-
tion nearly resembles that which is commonly practised by the refiners; it
differs only in not making use of lime to dissolve the sugar, according to the
usual process, but of common pond or river water, and in the clarifying with
whites of eggs in place of using bullock's blood, which is the practise of the
present refiners. The cauldrons to clarify resemble those which are described
in the process of working up the cane juice, adding only a copper plate, which
shuts up the aperture left in the front of the cauldrons at the second elevation,
and enables the sugar boiler to fill up the cauldron near to the uppermost brim.
The clarification effected, the sugar is deprived of those heterogeneous particles
which soil'd it. We therefore proceed to the evaporation of the fluid. To
effect this, the clarified or pure mass is put into boilers (vide the boilers
described for the cane juice) not above eight or nine inches deep, till it arrives
at that degree of contraction known by the term of point of proof in the
refineries; that is to say, that state of contraction which occasions the mass to
chrystalize as it cools, and to become a solid body, taking the form of those
molds into which it is cast, and seperating therefrom in an entire body when
compleatly cold. The state of contraction ought to be such as suffices for this
purpose, but should never be carried beyond it. The sugar being put i into
molds is treated in the same maner as in the common refineries, (viz³) it is
therein divided and moved while cooling, and when cold the mold is placed on
a pot or recipient, into which the first oosing runs; afterwards 'tis clayed
till the loaf becomes universally of an equal degree of whiteness. There
remains then to work up the sugar which has been accidentally carried away
with the scum, the unclouded syrup (or that which oozes spontaneously), and
the cloudy syrup (or that which oozes by the effect of claying). The sugar
carried away and mixed with the scum is recovered, as in the common
refineries, by diluting the skimmings with hot water; the sugar dissolves in
the water, and is seperated froin the indissoluble particles by means of a cloth,

page_text: which serves as a filter; the indissoluble particles remain on the surface; those
that are soluble pass through it. The former is of no use but to burn; the
latter, as well as the cloudy and clear syrups, chrystalize by the same process
and in the same utensils which are used for the cane juice. This chrystaliza-
tion pursued till the mass is totally exhausted, the sugar obtained therefrom
is purified in the same manner as raw sugar; the operation is precisely the
same, but the droppings which come from it do not chrystalize spontaneously;
'tis effected by evaporation on the fire, which must not take place with
respect to the droppings of raw sugar, which cannot be exposed to fire without
being entirely decomposed. When this chrystalization is purified, purged, or
clayed, it makes very white powdered sugar, which may be sold as it is, or of
which new sugar may be made by mixing it with clay'd sugar, as it then
appears infinitely finer than the clayed sugar itself.
The Cases to purge Raw Sugar.-They are the exact model of those draining
troughs described in the process of the cane juice, except that they are five
feet square and twenty inches deep; they are placed on trestles, in such a
manner that five trestles serve for two cases. The trestles placed at the
extremities are flat; that placed in the middle is ariss shaped; their length
must admit of the recipient being placed under the case.
Preparation of the clay resembles that observed in the present refinerics for
claying loaf sugar; but the clay used to clarify or purge raw sugar is thicker
than that used to clay loaves; it is carried to the consistence of a thick pap.
In witness whereof, I, the said Robert Murray, have hereunto set my
hand and seal, this Tenth day of November, in the year of our Lord
One thousand seven hundred and eighty-four.
ROBT MURRAY. (L.S.)
AND BE IT REMEMBRED, that on the Tenth day of November, in
the year above mentioned, the said Robert Murray came before our said Lord
the King in His Chancery, and acknowledged the Specification aforesaid, and
all and every thing therein contained and specified, in form above mentioned.
And also the Specification aforesaid was stampt according to the tenor of the
Statute made in the sixth year of the reign of Their Majestics King William
and Queen Mary of England, and so forth.
Inrolled the Tenth day of Noromban in