IMPROVEMENTS IN COOLING AND FREEZING MACHINES
Year: 1873

page_text: LETTERS PATENT to William Mort, of 155, Fenchurch Street, in the
City of London, for the Invention of "IMPROVEMENTS IN COOLING AND
FREEZING MACHINES."-A communication from abroad by Eugene
Dominique Nicolle and Thomas Sutcliffe Mort, both of Sydney,
in the Colony of New South Wales
Scaled the 18th November 1873, and dated the 19th June 1873.
PROVISIONAL SPECIFICATION left by the said William Mort at the
Office of the Commissioners of Patents, with his Petition, on the
19th June 1873.
I, WILLIAM MORT, of 155, Fenchurch Street, in the City of London,
5 do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN COOLING AND FREEZING MACHINES," to be as follows:
:―
My Invention consists of a mechanical combination which enables
me to utilize the waste cold resulting from frigoric mixtures, whereby
I can follow up the lowering of temperature to the extreme point at
which the salts used will dissolve.

page_text: My method of availing myself of this power enables me to freeze
water and refrigerate generally with certainty, safety, and cconomy;
the apparatus being continuous in its action, instantaneous in its results,
and requiring only a trifling power to work it.
way~I--
It is well known that the lower the temperature of the liquid used
in cooling mixtures for the dissolving of the salts the more intense
the cold produced, and I avail myself of this fact and utilize it in
my temperature exchanger by which I am enabled to impart to the
water and salts next to be used the surplus cold of the liquid last
used. In this way I can effect refrigeration with--the-most simple
and familiar ingredients, such as common salt, sugar, washing soda,
or any other crystallized salts which produce cold during liquifaction
the range of cold attainable, as before stated, being only limited by
the temperature at which the salts employed will liquify. For example,
common salt producing only three degrees of reduction of temperature
at 75° Fahrencit by the use of my apparatus reduces it from 75°
to 28°, or four degrecs below freezing point. Then again, nitrate of
ammonia giving only 46° reduction starting from the same point with
my apparatus gives and maintains zero, or 32° below freezing point.
!.!
In working I use by preference simple fixed salts which are soluble
in water, and requiring only to be evaporated to be again ready for
úsc.
Care must be taken to use in the construction of the apparatus
such pipes and vessels as will not be affected by the salts employed.
I now proceed to describe the apparatus. The salt employed is
placed into a receiver, at the bottom of which is a slide worked to
and fro by an eccentric on a shaft which rises up through the receiver.
In the slide is an aperture which, as the slide is moved to and fro,
passes alternately into and out of the receiver; when the aperture enters
the receiver it is filled with the salt, and when it passes out from the
receiver this measured quantity of salt falls on to an inclined shoot
which also has a small stream of water previously cooled, as herein-
after described, directed on to it. The water together with the salt
is conducted by the shoot into a vertical pipe which passes down
through the centre of a refrigerating well, and at the lower end of
the pipe they are delivered on to the centre of an agitator in the
form of a screw propeller composed of several blades; the blades, are

page_text: of such a shape and at such an angle as will counteract the centrifugal
force, and give a retrograde motion to the projected particles towards
the centre, thus causing a rapid dissolution of the salts employed.
The agitator is carried by a shaft which passes up through the vertical
tube above mentioned, and is driven at its upper end. On the upper
end of the shaft is also a pulley by which motion is transmitted to the
axis of the eccentric from which the salt measuring slide derives its
motion; this pulley can, by moving a clutch, be at any time set loose
on the shaft, and thus throw the measuring slide out of action.
'
The water with the salts dissolved in it passes by an overthrow into
one end of a freezing box or chamber in which the ice moulds, filled
with water or other articles requiring to be refrigerated, are placed;
it is made with divisions so as to cause the liquor to pass in a zig-zag
course through the. box, and at the opposite end of the box there is
an escape pipe by which the spent liquor passes away; the gradual
application of the cold, and the discharge of the spent liquor at a
temperature at which the water on its way to the water tender will
not freeze, is thus ensured, the ice moulds being moved in such manner
that as one mould is frozen the ice is taken out and the mould refilled
with water, and placed at the end where the spent liquor discharges,
the other moulds being moved on towards the opposite end where the
freezing liquor enters. The spent liquor as it passes from the freezing
box circulates through a coil of pipes contained in a hollow casing
of wood or other slow conducting material which surrounds the, rc-
frigerating well and freezing box; this hollow casing is filled up with
charcoal or other non-conducting material. The spent liquor after
passing through this coil enters a tank below the well and freezing
box; within this is a fresh water tank or vessel in which the water
next to be used for the purpose of ice making is cooled, so utilizing
any remaining cold which may be in the spent liquor. Through the
coil of pipe which conducts the spent liquor from the freezing box
to the spent liquor tank is passed a pipe of smaller diameter, the spent
liquor occupying the space between the two.
Water is supplied to one end of the smaller pipe from a receiver,
and at the opposite end it is conducted to the shoot herein-before
mentioned, on to which the measured supply of the salts is fed. The
circulation of the warmer and colder liquids through these pipes is
arranged to be in opposite directions, and if the pipes be in harmony

page_text: as to size, and the lengths be properly adjusted, a perfect exchange
of temperature will be effected between the two; one liquid leaving
at one end at the temperature the other entered, and vice versa.
By preference I use one pipe within another, as above described,
but I do not confine myself to this form of exchanger, as other
exchangers may be used; such, for instance, as a coil or spiral placed
in a vessel, one liquid flowing through the coil, and the other entering
and leaving the vessel in opposite directions.
If preferred the ice moulds may be removed from the freezing box
and be replaced by a coil, through which chloride of calcium or any
other vehicle for cold may be passed by action of a pump or other
mechanical contrivance, the cooling agent entering the coil where the
freezing liquor leaves the freezing box, and leaving that vessel on its
way to do its work where the freezing liquor enters.
The spent liquor as it passes away has subsequently to be evaporated
to recover the salts from it for reuse; this is effected continuously
in the following manner :-The spent liquor is passed through the coils
or pipes of an exchanger, meeting the evaporated liquid on its way from
the still in which it has been concentrated, and afterwards through the
coils or pipes of another exchanger, meeting the vapours passing from
the still.
The upper chamber of the still is fitted with evaporating plates on to
which the spent liquor falls, having in its course through the exchangers
before mentioned acquired a large amount of heat.
The liquor passes from plate to plate, receiving additional heat from
the vapour arising from the steam plates occupying the lower portion
of the still, and into which steam is admitted at suitable temperature.
In passing over the steam plate the necessary amount of water is
driven off, and the liquid leaves the still entering the exchanger first
mentioned to impart its heat to the liquor next to be acted upon.
The concentrated liquor is caused to drop on to a revolving drum
through which cold water is made to pass, by the cooling power of
which the salt is crystallized, and coming in contact with a scraper
is made to fall into a receiver, from whence, by endless belt or other
mechanical contrivance, it is carried into the salt receiver of the frigoric
machine, thus keeping up the supply in that vessel.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Mort in the Great Seal Patent Office on
the 18th December 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
MORT, of 155, Fenchurch Street, in the City of London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent bearing date the Nineteenth day of June, in the year of
our Lord One thousand eight hundred and seventy-three, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said William Mort, Her special license
that I, the said William Mort, my executors, administrators, and
assigns, or such others as I, the said William Mort, 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, exercise, and vend,"
within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN COOLING
AND FREEZING MACHINES," a communication to me from abroad by Eugene
Dominique Nicolle and Thomas Sutcliffe Mort, both of Sydney, in the
Colony of New South Wales, upon the condition (amongst others) that
I, the said William Mort, my executors or administrators, by an instru-
ment in writing under my, or their, or one of their hands and seals,
should particularly describe and ascertain the nature of the said In-
vention, 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 William Mort, 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 thereof, that is to say:-
-
This Invention consists of a mechanical combination which enables
waste cold resulting from frigorific mixtures to be utilized whereby
the lowering of temperature can be followed up to the extreme point at
which the salts used will dissolve.
The method of availing of this power enables water to be frozen and re-
frigeration generally to be carried on with certainty, safety, and economy,..
-

page_text: the apparatus being instantaneous in its results, and requiring only a
trifling power to work it, whilst its continuous action may be perpetuated
without any manual interference beyond the attention required in
keeping the motive power going, the water and the salts for cach succes-
sive manipulation being (where the evaporating apparatus is used in
combination with the freezing power) mechanically and continuously
supplied as the evaporation of the spent liquor goes on.
:
It is well known that the lower the temperature of the liquid used in
cooling mixtures for the dissolving of the salts, the more intense the
cold produced, and this fact is utilized by the employment of a tempera-
ture exchanger by which the surplus cold of the liquid last used is
imparted to the water and salts next to be used. In this way refrig-
eration can be effected with the most simple and familiar ingredients,
such as common salt, sugar, washing soda, or any other crystallized salts
which produce cold during liquifaction, the range of cold attainable as
before stated being only limited by the temperature at which the salts
employed will liquify. For example common salt producing only three
degrees of reduction of temperature at 75° Fahrenheit by the use of
this apparatus reduces it from 75° to 28° or four degrees below freezing.
point. Then again, chloride of calcium giving only 31° reduction
starting from the same point with this apparatus, gives and maintains a
point considerably below zero.
-The cold producing machine shewn upon the annexed plan and herein
described is designed for household purposes and to be worked by hand,
but it may of course be made of any size, according to the work required
of it, and be driven by any form of motive power which may be at
command, and may be worked in combination with the evaporating
apparatus herein-after described or not.
The shape of the vessels and the position they occupy may also be
varied to suit circumstances and conditions so long as the general prin-
ciple be observed.
In working the apparatus simple fixed salts are by preference used,
which are soluble in water and only require to be evaporated to be again
fit for use, such as nitrate of ammonia, chloride of calcium, &c., &c.
Care must be taken to use only such pipes and vessels as are not affected
by the salts employed. This is easily ascertained by placing a bit of the
metal proposed to be used in a solution of the salt intended to be em-

page_text: ployed; if the solution be discolored by the metal then that metal must.
be avoided.',
i)
I'now
now proceed to describe the apparatus which is styled "Nicolle and
Morts' frigorific machine," reference being had to Figures 1 and 2 of
the plan hereunto attached. (†
3
'
Figure 1 shew's a sectional elevation through the centre of the appa?
ratus; Figure 2 is a ground plan of the apparatus. A is a salt receiver
fitted witli a cone or inverted funnel in order to lead the salt to
the dis-
tributing slide Ę; B is a vertical shaft fitted at the base with an
eccentric to give backward and forward motion to the slide E; C'is'a
pulley fixed on the shaft B to which it gives motion; Dis a spade to
which a circular movement is given by an arm attached to the upper
part of the shaft B. This spade fills the aperture in the slide E with
the salts every successive stroke. E is a distributing slide which moves
freely between two dovetails receiving its motion from, the eccentric
above referred to. This slide is made witli an opening (by preference
oval) which is filled with salt cach time it enters the vessel A, emptying
itself on its return into the inclined shoot J; F is a water' tender fitted
at the base with a small pipe which serves to convey the water through
the exchanger and into the inclined shoot J; G is a temperature cx-
changer composed of a metallic cylinder with an external spiral channel
and a coil containing one pipe within another, tlie cylinder and the
coil being connected and both enclosed in some good non-conductor..
004
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107
The cylinder is made of a good conducting metal having a broad but
shallow spiral recessed on its outer side, such recess being covered with
an outer casing so as to form it into a channel, into the upper part of
which the spent liquor is made to enter on its return from its work, and
after having performed the circuit of the spiral to continue its course
through the outer pipe of the coil on its way to the tank S.
☑
I
The water next, required for the dissolution of thic salts enters the
inner pipe of the coil at the point where the spent liquor discharges, and
passing in an opposite direction exchanges temperature with that liquor
entering the cylinder at its base at or about the temperature at which
the spent liquor left that vessel. Upon entering the cylinder the water
comes into contact by conduction with the more intense cold of the
spent liquor which it absorbs, and if the cold be sufficiently intense it
will cause the congelation of the water against the inner surface of the

page_text: cylinder. The ice thus formed is continuously detached by a revolving
knife or scraper (which also acts as an agitator), and as detached, is
owing to its lighter gravity continuously passed into the tube K where
it joins the salt on its way into the refrigerating well.
If the refrigerated liquor be made to return to the spiral of the
cylinder without robbing it of too much of its cold on the way, the
whole of the water may speedily be passed into the tube in a frozen
state, whereby a very low range of temperature may be obtained, indeed
if crystallized chloride of calcium be the salt employed 49° below zero
or thereabouts will be the result if both salt and water be cooled.
In simple ice making the spiral cylinder may be dispensed with as the
temperature of the spent liquor after having done its work will never be
at freezing point.
I may here state that I do not confine myself to the form of this
vessel, as a similar result may be obtained by the spent liquor being
made to surround a metal vessel by coil of round or flat pipe, the water
entering the inner vessel, or one vessel may hold the water and be placed
in another vessel receiving the spent liquor, but by preference the form
first described is used.
The coil is composed of two pipes of different diameters, the smaller
pipe being placed inside the larger one, and of such proportions as to
allow the water from the tender F to circulate freely, whilst sufficient
space is left between the inner and outer pipe to allow the overflow from
the refrigerating well H as it passes from the spiral of the cylinder also
to circulate freely.
The principle of the exchanger is the circulation of a warmer and a
colder liquid in opposite directions within separate metallic pipes or
spaces, and if the pipes or spaces be in harmony as to size, and the
lengths be properly adjusted, say from 25 feet to 100 fect according to
the quantity of liquor to be passed, a perfect exchange of temperature
will be effected between the two, one liquid leaving at one end at the
temperature the other entered, and vice versa.
It may be observed that the pipes being in excess of the length
required will not be injurious to the working.
By preference one pipe is used within another, but I do not confine
myself to this sort of exchanger as any other form of temperature

page_text: exchanger may be used, such for instance as a coil or spiral placed in a
vessel, onc liquid flowing through the coil, and the other entering and
leaving the vessel in opposite directions, or one metal vessel may be
placed within another vessel, the spent liquor being made to enter one
of the vessels, and the liquid next to be employed in dissolving the salts
to enter the other.
The description just given has reference to the cooling of the water
only, but it will be found that in some cases it will be advantageous to
carry out the system still further and to cool the salt itself as well as the
liquid in which it is to be dissolved, as for instance where the salts
employed have a large capacity for heat. To effect this two different
modes may be used, one for the finer salts, the other for the coarser.
Where the salt is fine it is cooled by conduction, but where coarse by
absolute contact with the cold spent liquor, which latter plan may, if
preferred, be also used for the finer salts and vice versa.
For cooling by conduction a double metallic cylinder is employed;
that is, a cylinder with a water space outside it, and which space forms
a second or outer cylinder. Through this water space the spent liquor
flows, entering at the bottom and leaving at the top, thus moving in an
opposite direction to the salt.
The salt is conducted down the middle cylinder on its way to the
freezing well by means of a spiral made after the fashion of a screw;
propeller, and underneath which is a regulator for adjusting the flow of
the salt. This propeller which may be worked off the vertical shaft in
connection with the apparatus not only serves to pass the salt down but
keeps it constantly agitated, causing the crystals to come in fresh and
continuous contact with the cooled surface of the cylinder, and thus to
exchange temperature with the spent liquor.
For cooling by contact the following mode is employed:-The salt next.
to be used is allowed to fall in at the top of a vertical cylinder, in which'
is an agitator made after the fashion of the one herein described, and
working off the vertical shaft. The cold spent liquor is made to enter
through the bottom of this cylinder, and is forced upward by either
pump or gravitation through the salt passing out at the upper part into
the water exchanger, whereby its remaining cold is imparted to the
water next to be used. At one side of this vertical cylinder an aperturo
is made to allow the salt to pass into a closed vessel fitted against it at'

page_text: an angle, and in which vessel an elevator made after the manner of a
dredge ladder with perforated buckets is fixed. Endless motion is given
to the elevator by pulley worked off the vertical shaft, and by which
means the salt is raised from the bottom of the elevator vessel up to the
top where it is discharged into a shoot which leads it on its way to its
work into the central tube K.
By the agencies now described, if the supply of water and salt be
properly adjusted, both substances may be reduced to about the tem-
perature of the spent liquor after having performed its work.
H is the refrigerating well made of wood or other material, and by
preference lined with lead or other metal not affected by the salts used,
into which the salts and water pass by the tube K. H¹ is a freezing
box made by preference of wood lined with tin or lead, or other metal,
which the salts used will not affect, in which the ice moulds (filled with
water) or other articles requiring to be refrigerated are placed. It is
made with divisions so as to ensure the gradual application of the cold
and the discharge of the spent liquor at a temperature at which the
water on its way to the water tender will not freeze. I is a small
metallic pipe which conveys the water from the tender F through the
inner coil of the exchanger into the inclined shoot J. This pipe is fitted
with regulating cock in order to regulate the flow of water into the
shoot J. J is an inclined shoot which leads the water and the salts into
the central tube K. K is a central tube which leads the salts and the
water on to the centre of the agitator L. This tube is essential to the
proper working of the apparatus, as without it the water would escape
without proper contact with the salt, and if the water were introduced
at the bottom it would congeal. L is an agitator working in the
refrigerating well H, made with several blades in the form of a screw
propeller, and of such shape or angle as will counteract the centrifugal
force and give a retrograde motion to the projected particles towards the
centre, thus causing a rapid dissolution of the salts employed. M is a
vertical shaft, on which the agitator L is fixed, revolving in a step fixed
on the bottom of the refrigerating well H., N is a small driving pulley
revolving freely on the shaft M, fitted with a strap or band encircling
the pulley C, and giving motion to the shaft B. N¹ is also a driving
pulley communicating its rotary motion to a corresponding pulley on the
shaft of the scraper or knife in the spiral cylinder of the exchanger G.
O is a clutch fitted with a square hole on to the shaft M, which enables

page_text: 1
the salt spade and distributor to be thrown out of gear without inter-
fering with the motion of the shaft M. A thumbscrew serves to keep the
clutch in or out of gear as required: Pis a bracket, in which. thic
shaft M. revolves freely. Q is a handle for working the machine, which
can be replaced by a pulley where the machine is of: a size requiring
more than hand power. R is a U pipe rising to the level of the over-
flow to ensure the exchanger pipe, into which the spent liquor overflows,
being kept full so that the inner pipe containing the water may be.in
full contact with the cool liquor. S'is the spent liquor tank, into which
the spent liquor flows after exchanging its temperature with the water
coming from the tender F. Tis a delivery cock. U is a fresh water.
tank placed in the spent liquor tank S for the purpose of cooling the
water next to be used for icc making, utilizing any remaining cold which
may be in the spent liquor. V is a supply pipe for the purpose of
admitting water into the tank U. X is a cock for withdrawing the
water from the tank U. Y is a cock for drawing off the spent liquor
from the well H. Z is a cock for drawing off the liquor from the
:
.
The salt tank A must DC шlled with the salt intended to be used and
the water tender F with water, and be replenished as required. This
may be effected by mechanical means such as elevators, and be made
actually continuous in its operation by being worked in combination
with the evaporator.
The ice moulds must be filled with water and placed in the freezing
box H¹ with any other articles requiring to be refrigerated. These
things attended to the cock in the pipe I at the bottom of the water
tonder must be opened, and at the same time the machine must be put
in motion by turning the handle Q, this action must be continued until
the refrigerating well H, and the freezing box H₁ are full, when the
temperature of the liquid, if nitrate of ammonia be the salt used, will be
about 46° below. the temperature of the water at starting, but should
this not be the case before proceeding with the work the flow of water
must be lessened by adjusting the regulating cock so as to increase the
quantity of salt, and should it be found as the work proceeds that tho
salt admitted is in excess of what the water will take up, then the
clutch must be thrown out of gear and screwed to the shaft by the.

page_text: thumbscrew provided for that purpose and so kept until the salt in the
refrigerating box is dissolved. In this way the quantities may be
adjusted so that the flow of the water may be equal to the proper
dissolution of the salts as they are admitted. The vessels H and H¹
being full the overflow will begin to empty itself into the outside pipe of
the exchanger G, through the centre of which the fresh water from the
water tender is flowing in an opposite direction through the pipe I on
its way to the tube K, and an exchange of temperatures between the
two will commence, the spent solution discharging into the tank S at
the temperature the water left the water tender, and the water entering
the shoot J at the temperature the spent liquor left the freezing box H¹.
Fresh water may be introduced through the pipe V into the fresh
water tank U, from whence the ice moulds may be supplied by the
pipe X. It will be found that this water has taken up any cold which
was left in the spent liquor.
The operation will go on so long as the salt and water is supplied and
the apparatus kept in motion, the spent liquor being as continuously
withdrawn for evaporation through the pipe T; but in order to prevent
the spent liquor from freezing the water on its way to the shoot J it
will be necessary where the spiral cylinder is not used to remove the ice
mould next the refrigerating well (which it will be found will be first
frozen), and to move on the other, replacing the space at the end with
the same mould filled afresh with water.
I would here particularly observe that when artificial refrigeration is
required for purposes other than those referred to, the room or space
requiring to be kept cold is more or less surrounded with piping which
is connected at the cock Z, and through which the refrigerated liquor is
made to flow if needs be by a pump, and on its return to enter the
exchanger G. In working with the piping the passage of the liquor is
arranged by preference through two properly protected chambers so as
to give the extreme cold to the centre or frozen one, and then passing it
through the outer chamber in which the articles next to be frozen or
other articles requiring to be kept cool may be placed, the remaining
cold is utilized in reducing the temperature in the outer chamber. In
this way the work is carried on most effectively and the return is ensured
of the cooling agent to its entrance at the exchanger, at a temperature
which will not freeze the water, from the water tender on its way to the

page_text: shoot J, this latter however will be of no importance where the spiral
cylinder forms part of the temperature exchanger except where very low
temperatures are sought.
If preferred the ice moulds may be removed and replaced by a coil
through which brine or any other vehicle for cold may be passed by
action of a pump or other mechanical contrivance, the cooling agent
entering the coil where the freezing liquor leaves the freezing box or
well, and leaving that vessel on its way to do its work where the freezing
liquor enters, but where the salt employed for producing the cold will
not injure the metal through or over which it may have to pass, it may
of course be made to perform the work direct, and so do away with tho
necessity for the coil just described.
To avoid the expense of piping air may be made the cooling agent.
In this case air is passed through the refrigerating well H or the
refrigerating box H³, and then through, over, or around the vessels
required to be cooled, the air being made to pass by means of a common
air pump or fan.
The description given up to this point has reference only to the
working of the apparatus for the production of cold.
I will now describe the plan for continuously evaporating the spent
liquor whilst working and recovering the salts, reference being made to
Figure 3 of the plan hereunto annexed.
A is an exchanger made by preference of wood lined with lead or tin
containing a metal coil E, through which the spent liquor coming out
at the cock Z is forced on its way to another exchanger B. The spent
liquor is forced through the coil E, meeting the evaporated liquid on its
way from the still C to the crystallizing drum D, with which liquid it
partly exchanges temperature. B is another exchanger made by pre-
ference of like material to A, through which the coil E passes, the liquor
in that coil taking up additional heat from the vapour passing into the
vessel through the pipe F from the still C. The condensed water from
this vessel is conveyed by a coiled pipe through the condenser G. C is
a still, the upper chamber of which is somewhat after the fashion of
Coffey's still, and made by preference of wood lined with lead or tin
and fitted with ten or more perforated evaporating metal plates, on to
which the spent liquor falls, having in its course through the

page_text: exchangers A and B acquired a large amount of heat. The liquor
passes from plate to plate, receiving additional heat from the vapour
arising from three or more steam plates occupying the lower portion of
the still, and into which steam is admitted at suitable temperature by
the pipe H. These lower plates are best made of copper, tinned outside,
and of sufficient strength to bear the pressure of steam employed.
In passing over the steam plates the necessary amount of water is
driven off and the liquid leaves the still, and entering the exchanger A
imparts its heat to the liquor next to be acted upon..
D is a revolving drum made by preference of tinned copper, through
which cold water is made to pass, by the cooling power of which the
salt is crystallized, and which coming in contact with a scraper is made
to fall into a receiver, from whence by endless belt or other mechanical
contrivance it may be carried into the salt receiver of the frigorific
machine, thus keeping up the supply in that vessel. E is the metal
coil through which the spent liquor is forced through the exchangers A
and B on its way to the still C; F is a metal pipe through which the
steam and vapour from the still C is conveyed into the exchanger B, in
which vessel it is partly condensed; G is a condenser or cooler made by
preference of wood, into which cold water is allowed to flow for the
purpose of condensing the vapour and cooling the condensed water
coming from the exchanger B through the coil K, which latter is a
continuation of the pipe F. The condensed water falls into a closed
vessel L, from which it is pumped to the water tender of the frigorific
machine, which latter may thus be kept continuously supplied with
water, whilst a vacuum is maintained in the chamber L. H is a metal
pipe by preference copper, by which steam is admitted from any steam'
boiler to heat the steam plates in the still C. The steam after passing
through these plates is carried back to the water space of the boiler
through the pipe I.
The mode of working the evaporating apparatus is as follows, viz. :—
First pass steam by the pipe H at a temperature of about 275° so as to
thoroughly warm the still C, and then begin to pump the spent liquor
(which leaves the frigorific machine at the pipe T) through the pipe E,
which conveys it through the exchanger coils to the still C. As soon
as the liquor gets into circulation open the cock at the bottom of the
vessel L and let out the air; this repeat until all the air is expelled.
1

page_text: The salt as recovered may be passed into the elevator as before
described, and the process in that way may be made continuous.
Having thus described the nature of the Invention and the manner
of performing the same, I would have it understood that what is
claimed is,―
First. The combined arrangement of cooling and freezing machine,
substantially as herein described, and which may be worked with or
without the evaporating apparatus.
5
Second. The employment of temperature exchangers, substantially as
herein described for imparting the cold left in the spent liquor of frigorific 10
mixtures to the salt and the water (either or both) next to be employed
and by which a lower range of cold is obtained than otherwise could be
obtained from such mixtures.
Third. The employment of a central tube substantially as described.
herein and marked K on the plan, whereby the mixing water is 1
prevented from overflowing until saturated with the salt, and is
prevented from freezing by its union with the salt, as the two find their
way into the refrigerating well.
Fourth. The mode herein described of utilizing the cold left in the
spent liquor or other vehicle of cold after having done its work in or 20
over or around the frozen chamber on its return therefrom, and before it
reaches the temperature exchangers by passing it over, through, or
around a second or outer chamber, and by which, among others, the
following results are effected, viz*.-
1st. A valuable barrier is presented against the infiltration of heat 25
into the frozen chamber.
2nd. All the cold left in the cooling medium in excess of what is
required for cooling the water, and the salt next to be used is utilized in
cooling the articles next requiring to be frozen, or in the cooling of
rooms or spaces, or in the temporary preservation of food.
30
The importance of this will be understood when it is remembered
that it is not necessary to maintain a lower temperature than, say 25°
Fahrenheit in the frozen chamber, and allowing that the vehicle of cold
leaves at that temperature, it may absorb 25° of heat on its way through
the outer chamber and still enter the exchangers at 50°, a temperature 35

page_text: which would ensure the next charge being sent into the freezing chamber
at a point of cold which would admit of its leaving again at the normal
temperature of 25°, even allowing a reasonable margin for absorption of
heat in the chamber. At this temperature of 50° the salts dissolve
freely and a relatively larger amount of work will result than would be
obtained if the spent liquor returned to the exchangers at 25°.
In witness whereof, I, the said William Mort, have hercunto set
my hand and seal, this Tenth day of
in the year of
our Lord One thousand eight hundred and seventy-three.
,