Year: 1895

page_text: I, ETIENNE WILLIAMS KUHN of 42 Rue du Louvre, Paris, in the Republic of
France, Engineer, do hereby declare the nature of this invention to be as
follows:
The object of my invention is to provide a process of, and apparatus for the
absolute and scientific sterilization of liquids consisting in submitting them to the
action of heat and cold alternately, as and under the conditions hereinafter
explained so that the effect is homogeneous and takes place as instantaneously as
practicable throughout the body of liquid. The operations are performed in a
tightly closed chamber, preferably horizontal, and capable of receiving oscillatory,
gyratory, or equivalent movement such of the gases contained in the liquid treated
which tend to become disengaged during the heating, being retained and subjected
to such a pressure that during cooling, they are re-absorbed by the liquid. The
action due to the metallic vessel and the transformations which would result there-
from in the liquids under treatment are entirely avoided by coating the inner
surfaces of the chamber with silver or a metal such as those hereinafter defined.
The various applications of heat which have hitherto been tried for the sterili-
zation of liquids and more particularly for the sterilization of fermented liquids,
have not given quite satisfactory results for manufacturing purposes partly because
the processes employed do not permit the treatment of sufficiently large masses at
one operation, and partly because the changes brought about in the nature, or
condition of the liquid, by the treatment to which it was subjected in apparatus
such as have been used hitherto prevented the general application of the
processes.
The failures met with hitherto are explainable from the fact that the necessary
conditions as regards homogeneous and complete sterilization and the retaining
the liquid in an unaltered condition physically and chemically or organically
have never been before adequately obtained at one and the same time.
The absence of homogeneity or regularity in the effect produced and of com-
pleteness in sterilization is owing both to the absence of uniformity in and the
slowness of heating and cooling. The fact that the temperature is not regular
throughout the mass of liquid arises from the liquids being bad conductors of heat
so that it is not evenly diffused and consequently the transformation is not the same
throughout the different portions of the liquid unless the liquid be submitted to
agitation. The agitating or stirring devices hitherto employed for this purpose
have been attended by serious drawbacks as they interfered with the tightness of
Γ.
71

page_text: the chambers or receivers used op gave rise to the danger of considerable losses
of gas especially of carbonic acid gas in the case of fermented liquid which gas in
escaping carries away with it the aromatic principles which impart the peculiar
qualities to certain liquids; such as beer for example.
One of the reasons which have caused the abandonment of previous sterilizing
methods is due to certain peculiar and hitherto inexplicable disturbances which
take place in the liquids which are treated and which may manifest themselves
some considerable time after the operation. These disturbances have been hitherto
attributed to the action of heat but I have found by analysis that these
disturbances are due to the partial decomposition produced. by contact with the
metals hitherto employed and that the only metals which will not cause such
disturbances are platinum, gold, silver, and certain other metals of the same class,
such as palladium, and iridium. When metals other than these, come into contact
with a heated and fermented liquid, metallic hydroxides form and these react upon
the nitrogeneous and albuminoid matters contained in the liquid, and cause them
to be precipitated. Other reactions of a very complicated nature also take place
between the organic acids and metals; which reactions it is particularly important
to avoid especially where beer or milk for instance, is the liquid treated.
The object of this invention is to provide a process whereby the various incon-
veniences and objections above referred to are entirely avoided. It consists in
obtaining homogeneous, regular, and perfect sterilization without any physical,
chemical or organic change taking place in the liquid treated. This effect by
subjecting the liquid as rapidly as possible (without however superheating any part
thereof) to the sterilizing temperature, and then rapidly bringing it down again to
its initial temperature, by causing heated and cooled liquids to alternately circulate
in such a manner that the liquid being treated is presented in strata, of but small
depth, to the action of the heat and cold alternately.
The operation is carried out in a perfectly tightly closed receiver, capable of
resisting very high pressures such as those to which the liquid to be sterilized
exerts owing to the elevated temperature to which it has to be brought. An
oscillatory, gyratory or equivalent movement, of any suitable description is
imparted to the said closed receiver for rendering the temperature even, or
homogeneous throughout the liquid under treatment.
The said process may be carried out by means of apparatus of various forms; but
I prefer a horizontal cylinder, or vessel of small diameter or width compared to its
length.
It is advisable for example, that the length of the cylinder or vessel should be
at least six times greater than its diameter so that the liquid layer shall have but
little height, or depth, and by this means differences of temperature between the
top and bottom portions of the liquid are avoided.
To this cylinder a gyratory, or oscillatory, or equivalent, movement can be
imparted by mounting it upon spindles, pivots, rollers, or other similar devices
enabling it to be rotated or partially rotated through an angle varying say
between 180 degrees in each direction that is permitting it to complete an entire
semi-revolution in each direction so that what was before the top of the apparatus,
becomes its bottom, and vice versa, whereby an intermixture of the liquid layers
is effected and the liquid is consequently prevented from becoming divided into
layers, or zones, differing in temperature and density. The said cylinder, or
vessel, is provided with an outer casing, or jacket, and with tubes running through
its interior for the passage of the heating and cooling medium and the motion
imparted to it whilst enabling it to remain tightly closed, has the effect of causing
the said internal tubes to act as an agitating device of great efficacy which in the
most satisfactory manner effects the complete mixture of the liquid and ensures
homogeneousness of treatment throughout.
To avoid the treatment causing changes in the taste, flavour or odour, in the
liquids, treated the time of heating is made as short as possible too intense a
heat being avoided but the heating surfaces being as numerous, or extended, as

page_text: "
possible. Physiological effects are more rapilly obtained than physical or chemical
effects, and they bear a more direct relation to the factor" temperature" than to the
factor "time so that by rapid and brief application of high temperature a
zymotechnical sterilising effect is obtained, and, on this being obtained, the
application of heat should cease before it has time to bring about a chemical, or
physical, effect such as boiling, or other cause of undesirable changes due to the
continued action of heat. This most important prevention of undesirable changes
is effected by means of the inner tubes, and the outer casing, and the passage there-
through of a heating agent and then of an intensely cold agent, such as ice water,
or incongealable cold liquid. This combination of means enables the liquid treated
to be raised to the sterilizing temperature in a short time and to be maintained at
that temperature just as long as, and not longer than the tiine strictly necessary for
the attainment of the desired sterilising effect. When this is attained, the liquid
treated is immediately cooled down to its original temperature, the maintenance of
any intermediate temperature liable to prove harmful being carefully avoided..
This method enables sterilisation to be attained in a satisfactory manner whilst
avoiding the least modification in the taste odour or nature, of the liquid treated ;.
and it gives a result totally different from that obtained by the slow heating and
cooling processes performed in bottles.
By plating with silver, or other like metals, as hereinbéfore defined the metal
surfaces with which the liquids to be sterilised (more particularly fermented
liquors) would otherwise come into contact, decomposition is entirely avoided, and
therefore those injurious disturbances, which hitherto have been solely ascribed to
beat are prevented.
The apparatus employed may be arranged as follows. It consists of a tightly
closed cylinder say of copper. Its interior is silver-plated and it has a length
about six times greater than its diameter. It is arranged horizontally and traversed
longitudinally by a series of tubes set very closely together, and say of copper
and they are silvered on their exteriors. These tubes are arranged in horizontal
tiers and their ends are secured in front to the end plate over which is fixed a box,
or chamber, forming the end of the apparatus, the said box or chamber being
divided into a number of superposed compartments into which the ends of the
tubes open 80
as to constitute with the said tubes a continuous passage..
This chamber is connected with the cylinder by very closely set bolts, so that a
hermetically closed joint is formed. The bottom and top compartments have
respectively connected with the pipes constituting the inlet and exit for the
heating and cooling fluid.
The said cylinder is covered by a jacket with an inlet at one end and an outlet
At the other end for the entrance and exit of the heating and cooling fluid, to and
from the space between the jacket and cylinder. The said cylinder is supported
by rings which rest on rollers supported by a framing or support.
The apparatus is provided at the end with a pressure gauge a thermometer or
temperature indicator a liquid gauge, a filling and discharge cock and an air
exhaust cock. To the cylinder, handles are secured which enable the operator to
impart oscillation in both directions to the said cylinder with the greatest case and
with the requisite amplitude of movement (no matter what the dimensions, or the
weight, of the apparatus may be) owing to its being supported on rollers. In the
case of very large sized apparatus one of the rings may be replaced by a toothed
wheel with which engages a pinion by means of which rotary motion can be given,
to the cylinder.
The liquid to be sterilised having been filtered, or strained, if necessary, is, under
pressure, conveyed through the inlet pipe and cock into the cylinder, while the air-
contained in the latter escapes through an outlet or discharge cock therefor.
A line marked upon the water gauge indicates the point which should not be
exceeded in the level of liquid in the cylinder so as to allow of the necessary space
above for gases from the liquid under treatment, and of the requisite pressure, being
attained.

page_text: When the apparatus is filled sufficiently the cocks which were opened are close 1.
Hot water from any suitable source of supply is then admitted through the inlet
pipes therefor, which are fully opened for the purpose. The temperature of such
water should not exceed, by more than 10 degrees, the final temperature required
for sterilization, as any contact between the liquid treated and a surface heated to
a higher temperature would cause changes to occur in those portions of the liquid
so brought into contact with the superheated surfaces, and it is an object in
carrying out my invention to avoid this by ensuring absolute uniformity of heating
effect throughout the liquid under treatment. The hot water flows through the
rows of tubes in succession and through the compartments, so that it traverses the
said tubes in two directions passing from one end of the apparatus to the other and
then back again alternately, thus exerting its maximum heating effect in a
thoroughly equalized way upon the liquid under treatment.
On arriving at the upper compartment the liquid escapes through the outlet
therefor.
Hot water also passes through the jacket entering by the inlet and leaving by
the outlet.
The liquid to be treated being thus on all sides in contact with the heating
medium is, in a short time, raised to sterilising heat and when this has been attained
the supply of hot water is discontinued after the zymotechnical and physiological
effects of destruction of micro-organisms, or bacteria, have been produced, care
being taken to impart to the cylinder rotary, or oscillatory, movements, preferably
not less than 180 degrees in amplitude, the effect of such movements being to render
the temperature of the whole liquid mass perfectly uniform, or homogenous. The
pipes connected with the apparatus may be made of indiarubber, or other flexible
material, to enable them to follow the movements of the cylinder. When the
desired result is attained there is admitted through the same orifices as those by
which the hot water was previously admitted, and caused to circulate in the same
manner, ice water at about the zero temperature or, better still, incongealable
liquid at 10 degrees supplied from cold producing machines, which cooling
medium causes instantaneous cooling of the liquid under treatment to take place
and in a very short time the whole of the liquid will in consequence fall to its
initial low temperature.
During this cooling process, all the gases and vapours expelled but retained in
the cylinder during the heating process are again dissolved, resolved, and wholly,
absorbed by the cooled liquid.
The operation is then completed and the sterilised liquid, the other properties of
which have undergone no alteration whatever, may be decanted or drawn off for
use, or be introduced into casks, or other vessels, for shipment, or storage, the
necessary precautions of an antiseptic, or isobarometric, nature, being taken, so as
to avoid any infection from noxious germs and any subsequent loss of gas.
Dated this 9th day of April 1895.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.
CUBIT EIN
SPECIFICATION.
Improvements in and Apparatus for Sterilizing Liquids.
1, ETIENNE WILLIAMS KUHN of 42 Rue du Louvre, Paris, in the Republic of
France, Engineer, do hereby declare the nature of this invention and in what
manner the same is to be performed to be particularly described and ascertained.
in and by the following statement :-
The object of my invention is to provide a process of, and apparatus for, the
absolute and scientific sterilization of liquids, consisting in submitting them to the

page_text: action of heat and cold alternately as, and under the conditions, hereinafter
explained; so that the effect is homogeneous, and takes place as instantaneously
as practicable throughout the whole body of liquid. The operations are performed
in a tightly closed horizontal, or approximately horizontal, chamber, or vessel,
capable of receiving oscillatory, gyratory, or equivalent, movement, the liquid
occupying such a portion of the space inside the chamber, or vessel, that such of
the gases and volatile principles contained in the liquid treated, which tend to
become disengaged during the heating, are retained by the liquid after it has been
cooled. The action due to the metallic chamber, or vessel, and the transformations.
which would result therefrom, in the liquids under treatment are entirely avoided
by coating the inner surfaces of the chamber, or vessel, and the parts within it,.
with silver, or a metal such as those hereinafter defined.
The various applications of heat, which have hitherto been tried for the
sterilization of liquids, and more particularly for the sterilization of fermented
liquids, have not given satisfactory results for manufacturing purposes, partly
because the processes employed did not permit the treatment of sufficiently large
masses of liquid at one operation, and partly because the changes brought about
in the nature, or condition, of the liquid, by the treatment to which it was subjected,
in apparatus such as have been hitherto used, prevented the general application of
the processes.
The failures hitherto met with are due to the fact that, up to the present, means
have never been provided which fulfilled the necessary conditions for homogeneous
and complete sterilization whilst retaining the liquid in an unaltered condition
physically, chemically, and organically, and so as not to injure their value for
human consumption.
The absence of homogeneity, or regularity in the effect produced, and of
completeness in sterilization, is owing both to the absence of uniformity in, and
the slowness of, heating and cooling. The fact that the temperature is not regular
throughout the mass of liquid, arises from the liquids being bad conductors of
heat, so that it is not evenly diffused, and consequently the temperature is not the
same throughout the different portions of the liquid unless the liquid be submitted
to agitation. The agitating, or stirring, devices bitherto employed for this.
purpose have been attended by serious drawbacks, as they interfered with the
tightness of the chambers, or receivers, used, or gave rise to the danger of
considerable loss of gas, especially of carbonic acid gas, in the case of treating
fermented liquid, which gas, in escaping, carries away with it the aromatic
principles which impart the peculiar qualities to certain liquids, such as beer, for
example.
One of the reasons which have caused the abandonment of previous sterilizing
methods is due to certain peculiar, and hitherto inexplicable, disturbances which
take place in the liquids which are treated, and which may manifest themselves.
some considerable time after the operation. These disturbances have hitherto been
attributed to the action of heat, but I have found, by analysis, that they are due
to the partial decomposition produced by contact with the metals hitherto
employed for the apparatus, and that the only metals which will not cause such
disturbances are silver, platinum, gold and certain other metals of the same class,.
such as palladium and iridium. I will hereinafter refer to the metal which I use
as silver, as that is the metal practically best adapted for the purposes of my
invention. When metals other than these, come into contact with a heated and
fermented liquid, metallic hydroxides, form and these react upon the nitrogenous
and albuminoid matters contained in the liquid, and cause them to be precipitated.
Other reactions of a very complicated nature, also take place between the organic
acids, and the metals, which reactions it is particularly important to avoid,
especially where beer, or milk, for instance; is the liquid treated.
The object of this invention is to provide a process whereby the various
inconveniencies and objections herein before referred to are entirely avoided and
homogeneous, regular, and perfect, sterilization is obtained without any physical,

page_text: chemical, or organic, change taking place in the liquid treated, or its value for
human consumption being detrimentally affected. This I effect by subjecting the
liquid, as rapidly as possible, (without however superheating any part thereof), to
the sterilizing temperature, and then rapidly bringing it down again to its initial
temperature, by causing heated and cooled liquids to alternately circulate in such
a manner that the liquid being treated is presented in strata of but small depth, to
the action of the heat and cold alternately.
The operation is carried out in a perfectly tightly closed chamber, vessel, or
receiver, capable of resisting very high pressures, such as those which the liquid
to be sterilized exerts owing to the elevated temperature, to which it has to be
brought. An oscillatory, gyratory, or equivalent, movement is imparted to the said
closed vessel, or receiver, for rendering the temperature even, or homogeneous,
throughout the liquid under treatment.
The said process may be carried out by means of apparatus of various forms,
but I prefer a horizontal cylinder, or vessel, of small diameter, or width, compared
to its length.
It is advisable, for example, that the length of the cylinder, or vessel, should be
at least six times greater than its diameter, so that the liquid layer shall have but
little height, or depth, and, by this means, differences of temperature between the
top and bottom portions of the liquid are avoided.
To this cylinder, or vessel, a gyratory, or oscillatory, or equivalent, movement
can be imparted by mounting it upon spindles, pivots, rollers, or other similar
devices, enabling it to be partially rotated through an angle, varying say between
180 degrees in cach direction; that is permitting it to perform a semi-revolution
in each direction, so that what was before the top of the apparatus; becomes its
bottom and vice versa, whereby an intermixture of the liquid layers is effected, and
the liquid is consequently prevented from becoming divided into layers, or zones,
differing in temperature and density. The said cylinder, or vessel, is provided with
an outer casing, or jacket, and with tubes, or equivalent passages, running through
its interior for the passage of the heating and cooling medium, and the motion
imparted to it, whilst enabling it to remain tightly closed, has the effect of causing
the said internal tubes, or passages, to act as an agitating device of great efficacy,
which in the most satisfactory manner, efects the complete mixture of the liquid,
and ensures homogeneousness of the treatment throughout.
To prevent the treatment causing changes in the taste, flavour, or odour, of the
liquids treated, the time of heating is made as short as possible, too intense a heat
being avoided, but the heating surfaces being as numerous, or extended, as possible.
Physiological effects. are more rapidly obtained than physical, or chemical, effects,
and they bear a more direct relation to the factor "temperature," than to the
factor "time," so that, by rapid and brief application of high temperature, a zymo-
technical sterilizing effect is obtained, and, on this taking place, the application of
heat should cease before it has time to bring about a chemical, or physical, effect,
such as boiling, or other cause of undesirable change, due to the continued
action of heat. The inner tubes, or passages, and the outer casing, and the
passage therethrough of a heating agent, and then of an intensely cold
agent, such
as ice-water, or incongealable cold liquid, or brine, enables
the liquid treated to be raised to the sterilizing temperature in a short
time, and to be maintained at that temperature, just as long as, and not longer
thau, the time strictly necessary for the attainment of the desired sterilizing effect.
When this is attained the liquid treated is immediately cooled down to its original
temperature, the maintenance of any high, or intermediate, temperature, liable to
prove harmful, being carefully avoided. This method enables sterilization to be
attained in a satisfactory manner, whilst avoiding the least modification in the
taste, odour, or nature, of the liquid treated, and it gives a result totally different
from that obtained by the slow heating and cooling processes performed in bottles,
or like receptacles, in which the conditions hereinbefore defined have not been
provided for.

page_text: By plating with silver, or other like metals, as herein before defined, the injurious
metal surfaces. with which the liquids to be sterilized, (more particularly fermented
liquors), would otherwise come into contact, decomposition is entirely avoided, and
the injurious disturbances, which hitherto have been solely ascribed to heat, but
are due to contact with such injurious metal surfaces are prevented.
In the accompanying drawings I have shewn an apparatus suitable for use in
carrying this invention into effect, but I do not limit myself to the use of the
particular form, or proportions, of apparatus illustrated.
Figure 1, is an elevation of the apparatus partly in section, and
Figure 2, is an end view of the same seen from the entrance, or admission, end,
(being the left hand end of Figure 1).
Its
The apparatus consists of a tightly closed cylinder A, say of copper.
interior is silver plated, and it has a length of, say, at least, about six times greater
than its diameter. It is arranged horizontally, or practically horizontally, and is
traversed longitudinally by a series of tubes B, set very closely together, and say
of copper, and they are silvered on their exteriors. These tubes are arranged in
horizontal tiers, and their ends are secured in front to the end plate, over which is
fixed a box, or chamber, C, forming the end of the apparatus, the said box, or
chamber, C, being divided into a number of superposed compartments c, into which
the ends of the tubes B, open, so as to constitute, with the said tubes, a continuous
passage. This chamber C, is connected with the cylinder by very closely set
bolts, so that a hermetically closed joint is formed. The bottom and top com-
partments c, have respectively connected with them, the pipes D, and E, constituting
the inlet and exit for the heating and cooling agent.
The said cylinder A, is covered by a jacket. F, with an inlet at one end, and an
outlet at the other end (f, f*,) for the entrance and exit of the heating and cooling
fluid, to, and from, the space between the jacket F, and cylinder A. The said
cylinder A, is supported by the rings a, which rest on rollers g, supported by the
framing, or support, G.
The apparatus is provided at the end with a pressure gauge H, a thermometer,
or temperature indicator, I, a liquid gauge J, a filling and discharge cock K, and
an air exhaust cock L. To the cylinder A, handles a', are secured which enable
the operator to impart oscillation in both directions to the said cylinder with the
greatest ease, and with the requisite amplitude of movement, (no matter what the
dimensions, or the weight, of the apparatus may be), owing to its being supported
on rollers. In the case of very large sized apparatus one of the rings a, may be
replaced by a toothed wheel, with which engages a pinion by means of which
semi-, or partial rotary motion can be given to the cylinder A, or any other suitable
means for giving the necessary motion to the cylinder can be used.
The liquid to be sterilized having been filtered, or strained, if necessary, is,
under pressure, conveyed through the pipe and cock K, into the cylinder A,
while the air contained in the latter, escapes through the outlet, or discharge,
cock L.
A line, marked upon the liquid gauge J., indicates the point which should not
be exceeded in the level of liquid in the cylinder, so as to allow of the necessary
pressure being attained and of the necessary space above for permitting the gases
and volatile principles of the liquid under treatment to remain in such a way that
chemical disassociation is prevented and retention of the said gases and volatile
principles is ensured when the pressure is relieved on cooling.
When the apparatus is filled sufficiently the cocks K, and L, are closed. Hot
water, or other heating agent, from any suitable source of supply, is then admitted
through the pipes D, and f, which are fully opened for the purpose. The tem-
perature of such water, or heating agent, should not exceed by more than say
10 degrees, the final temperature required for sterilization, as any contact between
the liquid treated and a surface heated to a higher temperature would cause
changes to occur in those portions of the liquid so brought into contact with the
superheated surfaces, and it is an object in carrying out my invention to avoid

page_text: this by ensuring absolute uniformity of heating effect, throughout the liquid
under treatment. The hot water, or other heating agent, flows through the rows
of tubes B, in succession, and through the compartments e, as indicated by the
arrows, so that it traverses the said tubes in two directions, passing from one end
of the apparatus to the other, and then back again alternately, thus exerting its
maximum heating effect in a thoroughly equalized way upon the liquid under
treatment, and, on arriving at the upper compartment c, the liquid escapes through
the outlet E.
Hot water, or other heating agent, also passes through the jacket F, entering by
the inlet, and leaving by the outlet f".
.
The liquid to be treated being thus in contact on all sides with the heating
medium is, in a short time, raised to sterilizing heat, and, when this has been
attained, the supply of hot water, or other heating agent employed, is discon-
tinued after the zymotechnical and physiological effects of the destruction of
microorganisms, or bacteria, have been produced, care being taken to impart to the
cylinder A, alternating-rotary, or oscillatory, movements, preferably not less than
180 degrees in amplitude, the effect of such movements being to render the
temperature of the whole liquid mass perfectly uniform, or homogeneous. The
pipes connected with the apparatus, may be made of india rubber, or other flexible
material, to enable them to follow the movements of the cylinder. When the
desired result is attained, there is admitted, through the saine passages as those
by which the hot water, or other heating agent, was previously admitted, and
caused to circulate in the same manner, the cooling agent, say ice water, at about
the zero temperature, or, better still, incongealable liquid at 10 degrees C. supplied
from cold producing machines, which cooling medium causes instantaneous cooling
of the liquid under treatment to take place, and in a very short time, the whole
of the liquid will in consequence fall to its initial low temperature.
-
During this cooling process, all the gases and volatile principles are retained by
the cooled liquid which thus does not lose its original properties.
The operation is then completed and the sterilised liquid, the other properties
of which have undergone no substantial alteration whatever, may be decanted, or
drawn off, for use, or be introduced into sterilized casks, or other vessels, for
shipment, or storage, if necessary the precautions being taken of previously washing
the vessel with an antiseptic and subsequent introduction of the fluid by isobaro-
metric pressures into such vessels so as to avoid any infection from noxious germs,
and any subsequent loss of gas.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. The herein before described improved process of sterilization of liquids,
consisting in first submitting them to the homogeneous and instantaneous action of
heat, not however exceeding, (or exceeding very slightly), the temperature necessary
for sterilization, and then cooling the same, also in a homogeneous and instantaneous
manner, such heating and cooling operations being intermittently performed in a
hermetically closed horizontal, or practically horizontal, cylinder, or vessel, to which
oscillatory, gyratory, or equivalent, motions are imparted, the conditions being
such as aforesaid that the gases and volatile principles of the liquid treated are
retained and injurious action of metallic surfaces being avoided by the employment
of coatings of silver, or equivalent metal proof against the actions of liquids, such
silver, or the like, being applied to the surfaces of, and in, the said cylinder, or
vessel, with which the liquid comes in contact, substantially as hereinbefore
described.
2. Apparatus for the purpose described; the said apparatus consisting of
tightly closed horizontal, or practically horizontal, cylinder, or vessel, for containing
the liquid to be treated, and of a diameter, or width, small in comparison to its
length, and provided with a casing, or jacket, and a series of tubes, or passages, in

page_text: the interior of the said cylinder, or vessel, and means for supplying a heating
agent and a cooling agent to the said jacket and tubes, or passages, and means for
imparting a gyratory, oscillating, or equivalent, motion to the said cylinder, or
vessel, the surfaces in, and of, the cylinder being coated with silver, or equivalent
metal all substantially as hereinbefore described and illustrated in the accompanying
drawings.
Dated this 8th day of January 1896.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.