IMPROVEMENTS IN SURFACE CONDENSERS, ALSO APPLICABLE TO GERATION OR COOLING OF FLUIDS
Year: 1863

page_text: LETTERS PATENT to Henry Cochrane, of Ormesby Iron Works, Middles-
borough-on-Tees, in the County of York, Engineer, for the Invention of
"IMPROVEMENTS IN SURFACE CONDENSERS, ALSO APPLICABLE TO
GERATION OR COOLING OF FLUIDS"
Sealed the 29th December 1863, and dated the 30th October 1863.
PROVISIONAL SPECIFICATION left by the said Henry Cochrane at
the Office of the Commissioners of Patents, with his Petition, on the
50th October 1863.
I, HENRY COCHRANE, of Ormesby Iron Works, Middlesborough-on-Tees,
in the County of York, Engineer, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN SURFACE CONDENSERS, ALSO APPLICABLE TO THE
REFRIGERATION OR COOLING OF FLUIDS," to be as follows:-
My.Invention has reference to that class of surface condensers known as
"evaporative surface condensers," in which the condensation of steam is
effected by passing the same through tubes or pipes, upon the outer surface of
which a small quantity of water is made to flow, the evaporation of such
[Price 8d.1

page_text: water effecting the condensation of the steam within the tubes or pipes. Such
evaporative surface condensers have been variously constructed, and Patents
for such arrangements have been obtained by Clark in 1822 (No. 4665), by
Pirsson in 1858 (No. 899), by Perkins in 1858 (No 2124), by Pontifex in
1858 (No. 2620), and by Howden in 1860 (No. 2854); but in all these
arrangements the steam is made to pass through the inside of tubes of
comparatively small diameter, whilst the condensing water is made to fall
upon the exterior of such tubes. These arrangements have the dis-
advantages, firstly, of requiring a great volume of condensing water to
produce the necessary degree of condensation; and, secondly, of having a
number of pipe joints that are with difficulty maintained in proper work-
ing condition.
Now, my Invention has for its object the remedying of these defects, and
consists in constructing such evaporative surface condensers of a narrow
annular vertical chamber, into which the steam to be condensed is made to
pass, whilst a small quantity of water is made to flow down the outer surface
of both the in'ernal and external walls of the chamber. Thedistance between
the internal and external walls is made to be very small, whereby the steam is
caused to come in most intimate contact with them, and thus becomes
thoroughly condensed by the absorption of its heat consequent on the
evaporation of the water from the outer surfaces of the walls, which are made
of iron or other metal that is a good conductor of heat. I prefer to construct
such condensers in the following manner:-Two pipes, tubes, or cylinders of
cast iron or other suitable metal of moderate thickness and of different
diameters are placed the one within the other, the differenceof their respective
diameters being such as to leave a narrow annular space between them c n-
stituting the before-mentioned chamber into which the steam passes. This
space is closed in an air-tight manner at the lower extremity of the cylinders
by their being fitted into an annular trough formed on an annular plate upon
which they stand; between the sides of this trough and the sides of the tubes
there exist spaces that are filled in to a certain extent with lead, cement, or
other suitable material. At the top the annular chamber is closed by a pro-
jecting rin being formed on the inner surface of the outer tube a short
distance down from the top of the same which rim fits against the outer
surface of the inner tube, and the space between the two tubes abovethis rim
is filled in to a certain extent with lead, cement, or other suitable material;
and in order to seal both this joint and the lower one in the most perfect
manner, the space above the lead or cement in the annular grooves is filled in

page_text: with water; by this means perfectly air-tight.joints are obtained in the most
simple possible manner. The eduction pipe from the steam engine commu-
nicates with the top part of the annular chamber through an aperture formed
in the outer tube, and the water of condensation passes away at the bottom
through an aperture formed in the annular plate before mentioned. An
annular trough continuously supplied with cold water is attached to the top
of the inner and outer tubes in such a manner that narrow apertures are
formed against the sides of the tubes through which the water can trickle
down in a thin film over the outer surfaces of these tubes, the passage of the
water being further regulated by the application of rings of lead or other soft
material attached to the trough, and having their edges projecting below the
latter, so as to be capable of being brought as close to the outer surfaces of
the tubes as may be required, the water being made to flow between the edges
of such rings and the surfaces of the tubes. The condenser is supported upon
standards, framing, brickwork, or other foundation, in such a manner as to
facilitate the passage of the air through the inner tube, and the current of air
may be further increased, and consequently the evaporation of the condensing
water accelerated, by forcing or drawing the air through the inner tube bythe
aid of a fan, or by connecting that space with a boiler or other flue. The
outer tube may also be surrounded at some distance by a casing, through
which a current of air would be induced by the heat given off from the tube,
and the evaporation of the condensing water thus accelerated. I prefer to
make the tubes or cylinders of a large diameter and of some considerable
height, so that one such annular chamber only is required for affording
sufficient condensing surface, but several such annular chambers of smaller
dimensions inay be combined, either concentrically or otherwise, to forin a
surface condenser.
Although I prefer to make the tubes of a cylindrical form, yet they may be
of any other transverse sectional form, and they may be formed with flutings
or corrugations to increase the surface.
My improved evaporative surface condenser may also be applied to the
cooling or refrigeration of fluids by passing such fluids through the annular
chamber in place of the steam, as before described.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Henry Cochrane in the Great Seal Patent Office on the
11th March 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
COCHRANE, of Ormesby Iron Works, Middlesborough-on-Tees, in the County of
York, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirtieth day of October, in the year of our Lord
Onethousand eight hundred and sixty-three, in the twenty-seventh year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Henry Cochrane, Her special licence that I, the said Henry Cochrane,
my executors, administrators, and assigns, or such others as I, the said Henry
Cochrane, 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, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN SURFACE
CONDENSERS, ALSO APPLICABLE TO THE REFRIGERATION OR COOLING OF FLUIDS,"
upon the condition (amongst others) that I, the said Henry Cochrane, 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 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 Henry Cochrane, do hereby declare the
nature of the said Invention, and in what manner the same is to be performed,
to he particularly described and ascertained in and by the following statement
thereof reference being had to the accompanying Drawings, and to the figures
and letters marked thereon, that is to say:-
My Invention has reference to that class of surface condensers known as
"evaporative surface condensers," in which the condensation of steam is
effected by passing the same through tubes or pipes, upon the outer surface of
which a small quantity of water is made to flow, the evaporation of such water
effecting the condensation of the steam within the tubes or pipes. Such
evaporative surface condensers have been variously constructed, and Patents
for such arrangements have been obtained by Clark in 1822 (No. 4665), by

page_text: Pirsson in 1858 (No. 899), by Perkins in 1:58 (No. 2124), by Pontifex in
1858 (No. 2620), and by Howden in 1860 (No. 2854); but in all these
arrangements the steam is made to pass through the inside of tubes of com-
paratively small diameter, whilst the condensing water is made to fall upon
the exterior of such tubes. These arrangements have the disadvantages,
firstly,of requiring a great volume of condensing water to produce the necessary
degree of condensation; and, secondly, of having a number of pipe joints that
are with difficulty maintained ia proper working condition.
Now my Invention has for its object the remedying of these defects, and
consists in constructing such evaporative surface condensers of a narrow
annular chamber, into which the steam to be condensed is made to pass,
whilst a small quantity of water is made to flow down the outer surface of both
the internal and external walls of the chamber. The distance between the
internal and external walls is made very small, whereby the steam is caused to
come in most intimate contact with them, and thus becomes thoroughly
condensed by the absorption of its heat consequent on the evaporation of the
water from the outer surfaces of the walls, which are made of iron or other
metal that is a good conductor of heat. I prefer to construct such condensers
in the following manner :-Two pipes, tubes, or cylinders of cast iron or other
suitable metal, of moderate thickness and of different diameters, are placed the
one within the other, the difference of their respective diameters being such as
to leave a narrow annular space between them, constituting the before-
mentioned chamber into which the steam passes. This space is closed in an
air-tight manner at the lower extremity of the cylinders by these being fitted
into an annular trough formed on an annular plate upon which they stand;
between the sides of this trough and the sides of the tubes there exist spaces
that are filled in to a certain extent with lead, cement, or other suitable
material. At the top the annular chamber is closed by a projecting rim being
formed on the inner surface of the outer tube, a short distance down from the
top of the same, which rim fits against the outer surface of the inner tube, and
the
space
between the two tubes above this rim is filled in to a certain extent
with lead, cement, or other suitable material, and in order to seal both this
joint and the lower one in the most perfect manner, the space above the lead
or cement in the annular grooves is filled in with water. By this means
perfectly air-tight joints are obtained in the most simple possible manner.
The eduction pipe from the steam engine communicates with the top part of
the annular chamber through an aperture formed in the outer tube, and the
water of condensation passes away at the bottom through an aperture formed

page_text: in the annular plate before mentioned. An annular trough, continuously
supplied with cold water, is attached to the top of the inner and outer tubes in
such a manner that narrow apertures are formed against the sides of the
tubes, through which the water can trickle down in a thin film over the outer
surfaces of these tubes, the passage of the water being further regulated by the
application of rings of lead or other soft material attached to the trough, and
having their edges projecting below the latter, so as to be capable of being
brought as close to the outer surfaces of the tubes as may be required, the
water being made to fl w between the edges of such rings aud the surfaces of
the tubes. The condenser is supported upon standards, framing, brick work,or
other foundation in such a manner as to facilitate the passage of the air through
the inner tube, and the current of air may be further increased, and con-
sequently the evaporation of the condensing water accelerated, by forcing or
drawing the air through the inner tube by the aid of a fan, or by connecting
that space with a boiler or other flue. The outer tube may
also be surrounded
at some distance by a casing, through which a current of air would be induced
by the heat given off from the tube, and the evaporation of the condensing
water thus accelerated. I prefer to make the tubes or cylinders of a large
diameter, and of some considerable height, so that one such annular chamber
only is required for affording sufficient condensing surface; but several such
annular chambers of smaller dimensions maybecombined, eitherconcentrically
or otherwise, to form a surface condenser.
Although I prefer to make tubes of a cylindrical form, yet they may be of
any other transverse sectional form, and they may be formed with flutings or
corrugations to increase the surface.
My improved evaporative surface condensers may also be applied to the
cooling or refrigeration of fluids by passing such fluids through the annular
chamber in place of the steam, as before described.
But in order that my Invention may be readily understood and carried
int effect, I will now proceed more particularly to describe the best means
I am acquainted with of performing the same.
On the accompanying Drawings are shewn various arrangements of which
my improved evaporative surface condenser is susceptible.
Figures 1 to 4 on Sheet I. shew the arrangement which I prefer to employ.
Figure 1 shews an elevation; Figure 2 shows a plan; Figure 3 shows a
sectional elevation; and Figure 4 shows a sectional plan. The same letters
of reference indicate the same parts in each of the Figures.
A is the annular chamber, in which the condensation of the steam takes

page_text: place; it is formed between the two pipes, tubes, or cylinders B and C, of
which the latter is made of a smaller diameter than the former. These
cylinders are of thin cast iron or other suitable metal, and the annular space
between them is closed at the lower end by their being fitted into the annular
trough D formed on the annular plate E, whilst at the upper end the outer
cylinder B is provided with an internal fillet b, fitting against the outer surface
of the cylinder C. Lead, cement, or other suitable caulking is run into the
narrow spaces left between the sides of the trough D and the cylinders, as
also into the annular space at top between the two cylinders above the
fillet b, a space being left above the caulking, both at top and bottom, into
which spaces water is introduced for the purpose of rendering the joints
perfectly air-tight. An annular trough F, open at the bottom, rests upon the
top of the cylinders B, C, by means of the ribs f.f, connecting the two sides
of the trough, narrow annular spaces being made to intervene between the
latter and the sides of the cylinders, as shown, through which spaces the water
that is supplied to the trough by the service pipe G and branches g, g, runs
down in a thin film over both the external surface of the cylinder B and the
internal surface of the cylinder C. In order to regulate the quantity of water
that flows down these surfaces with the greatest nicety, rings of lead H, I,
attached to the lower edges of the trough F, are made to project beyond the
bottom of the same, and are brought close to the surfaces of the cylinders, as
shown; and as the degree of this proximity may be readily adjusted by means
of a hanımer, the quantity of water that passes through between the lead
rings and the sides of the cylinders may be accurately regulated. The lead
rings are pressed firmly against the sides of the trough by means of iron
hoops J, K, and are prevented from slipping down by strips h, i, bent over
the upper edges of the trough. The steam to be condensed passes into the
annular chamber A through the pipe L, and in passing down through the
same becomes effectually condensed, the water of condensation being
exhausted from the chamber through the aperture e in the plate E and
pipe M, leading to the air pump. The small quantity of water that falls
from the condenser into the tank N after filling the annular spaces in the
trough D, is conducted thence through the pipe O to a pump for forcing it
back into the supply reservoir, to be used over again. The condenser is
supported by four standards P, P, P, P, bolted to the plate E and to the
foundation plate Q, resting on the masonry of the tank N, by which
arrangement free access of air is permitted to the central space of the
condenser, so as to accelerate the evaporation of the water.

page_text: Figures 5 and 6 on Sheet II. shew respectively a sectional elevation and
a sectional plan of an arrangement in which the condenser consists of three
concentric annular chambers A, B, C, each of which are similar in con-
struction to that just described. The plate D upon which the cylinders stand
is provided with suitable openings between each of the annular troughs
formed upon it, as also in the centre, as shown, to admit of the passage of
the air through the annular spaces between the chambers and the central
space of the chamber C for facilitating the evaporation of the water.
In order to insure the perfect condensation of the steam, the communications
of the chambers with each other and with the exhaust steam pipe and air
pump are arranged in the following manner :-The steam enters the outer
chamber A at the top through the pipe E, it then passes down this chamber
and passes near the bottom through the pipe F into the chamber B, and
after passing up through the same enters the chamber C through the pipe G
at the top; the water of condeusation resulting from all three chambers is
removed through the pipe H connecting the inner chamber with the air pump,
the water of condensation from the chambers A and B being made to pass
into C through the connecting pipe I. This pipe should be of such a depth
that there is always a sufficient column of water in it to prevent the steam
passing directly through the same from the chambers A and B-into C; J,K,L,
are annular troughs to each of the chambers, supplied with water from the
pipe M, and arranged as described with reference to Figures 1 to 4, Sheet I.,
for allowing a thin film of water to flow down the inner and outer walls of
each chamber; the waste water is caught in the tank N, whence it is
removed through the pipe O. This tank serves also as the pedestal to the
condenser, the plate 1 of the latter resting upon bearers P, P, carried in
pockets formed on the sides of the tank. In order to insure a free passage
of air to the annular spaces between the chambers, apertures are formed in
the sides of the tank N, as shewn.
Instead of three annular concentric chambers, any other number of the
same may be combined to form a condenser, and in place of their being
arranged concentrically, several smaller chambers of equal size may be placed
separately in the central space of one larger one, or they may be arranged as
shewn in elevation and sectional plan at Figures 7 and 8, where the four
annular chambers A, B, C, D, are arranged and connected so as to form one
condenser, the steam first passing into A, through the pipe E near the bottom,
then from the top of A, into the top of B, through the pipe F, then from the
bottom of B into the bottom of C through the pipe G, and from the top of C

page_text: into the top of D through the pipe H; the water of condens ition resulting
from all four chambers is drawn off from the chamber D through the pipe I,
the other chambers communicating at the bottom with the latter by means
of bent.pipes, as described in the former arrangement. The other details of
this arrangement are similar to those of the one before described. In place of
making the tubes or cylinders composing the chambers of a circular trans-
verse sectional form, they may be made of any other suitable form, aud
where it is required to produce a considerable amount of condensing
surface in a small space they may with advantage be formed with
corrugations or flutings, as shown in the sectional plan at Figure 9.
the
Figure 10 shows a sectional elevation, and Figure 11 an end elevation of
another arrangement of which my improved evaporative surface condenser is
susceptible. Here the annular chambers A, B, C, are placed one above the
other in a horizontal position, being supported by a framing D, D, at either
end. The condensing water requisite for the outer surfaces of the chambers is
supplied from the trough E with perforated bottom, also supported by the
framing D, D, whilst for supplying the condensing water requisite for the inner
walls of the chambers, the water supply pipe F to the trough E is continued
down at one end of the apparatus, and branches G, H, I, from the same pass
through the central spaces of the chambers, as shewn, and are perforated on
upper part of their surface, so as to cause a number of small jets of water
to be tlirown against the upper part of the inner cylinders. This water runs
down the sides of the cylinders and produces the requisite degree of condensa-
tion by its evaporation. The two cylinders forming each of the annular
chambers are connected together at both ends in a similar mauner to that
describedwith reference to theupper end of the arrangement shown on Sheet I.
of the Drawings, either the inner or the outer cylinder having a projecting
fillet formed near each end of the outer or inner surface, as the case may be,
or the outer cylinder may have a fillet near the one end of its inner surface,
and the inner cylinder may have one near one end of its outer surface. Lead,
cement, or other suitable caulking is then run into a portion of the annular
space beyond the closing fillets, and the remaining annular spaces a, a, b,b,c,c,
at each end of the chambers are closed in by any suitable means as indicated,
.and apertures a', a¹, b1, b, c, cl, being made in each of the outer cylinders, the
water that falls from the trough and from the chambers is ca used to fill the
annular spaces a,a,b,b, c, c, whereby the joints are rendered perfectly air-tight.
The steam passes from the exhaust pipe J into the chamber A, and from
thence, together with the water of condensation, through the pipe K into

page_text: the chamber B, whence it passes into the chamber C through the pipe L.
The whole of the resulting water of condensation is drawn off by the air
pump from the chamber C through the pipe M. N is the tank or tray for
catching the waste condensing water, as in the other arrangements.
Figures 12 and 13 on Sheet III. show respectively a sectional elevation
and a sectional plan of another arrangement of my improved condenser. Here
the annular chambers A, B, C, are of a flattened form, so as to afford con-
siderable condensing surface in a very compact space. The troughs D, E, F,
for supplying the condensing water are shown closed at the top to prevent the
water from spilling when the condenser is employed for marine engines.
The exhaust steam passes into the top of the chamber A through the pipe G,
then from the lower part of the same through the pipe L into the lower
part of the chamber B, from the top of which it passes into the chamber C
through the pipe H; I is the pipe from the latter chamber to the air
pump, and J and K are pipes for conveying the water of condensation from
the chambers A and B into C. The other details of construction are similar
to those of the previous arrangements and require no further description.
In all the foregoing arrangements, where several chambers are combined
to form one condenser, instead of causing the steam to pass into the several
chambers in the manner there described, I sometimes cause the steam to pass
from the eduction pipe directly into each chamber, in which case I provide
each branch pipe from the eduction pipe with a baffler valve, and throttle
the steam on its passage into those chambers which it first enters from
the eduction pipe to such an extent as to distribute the whole volume of
steam to be condensed equally in all the chambers. Each chamber is, in
that case, made to communicate directly by means of branches with the
pipe leading to the air pump.
In cases where the exhaust steam from a number of steam engines is made
to pass through one main exhaust pipe into a number of my improved evapo-
rative surface condensers, I prefer to admit the steam into the latter in the
just described manner, and I then conveniently arrange such evaporative
surface condensers as shown in plan at Figure 16 on Sheet I. of the Drawings.
The condensers A, A, A, A, are arranged in one or more rows, and the steam
enters them from the main exhaust pipe B, B', through the branches b, b, b.
Each of these branch pipes is provided with a baffler valve c, c, c, by means of
which the steam is throttled to such an extent, on passing into the condensers
nearest the eduction pipe B, as to prevent more steam from passing into these
condensers than into those that are farthest from the pipe B. All the con-

page_text: densers are also connected by means of the pipes C, C¹, to one main pipe C2
leading to the air pump or pumps. Should at any time any number of the
steam engines stop working, a corresponding number of the condensers are
also put out of action by simply closing the baffler valves and shutting off the
supply of water; they are, however, still left in communication with the air
pump, so that a vacuum is maintained in them.
It will be evident that any of the before-described arrangements of my
improved evaporative surface condenser may also be employed for the refri-
geration or cooling of fluids by simply passing the fluid to be cooled through
the annular chambers in place of steam; for brewing purposes, however, it is
generally preferred that the apparatus should be open, in order that the liquor
may be capable of inspection whilst undergoing the process of refrigeration;
for this purpose, therefore, I prefer to employ an apparatus as shown in trans-
verse section and plan at Figures 14 and 15 on Sheet III. of the Drawings.
The refrigerator is composed of four concentricannularchambersor receptacles
A, B, C, D, all of which are open at the top, as also are the upper passages
E, F, connecting the receptacles A, B, and C, D. The annular receptacles,
instead of being formed each of two separate cylinders connected to one
common base plate, as in the former arrangements, are in this case formed by
the inner and outer cylinder, which are of thin copper or other suitable metal,
being brazed or otherwise connected together at the bottom. The troughs
G, H, I, J, for supplying the condensing water to the surfaces of the annular
receptacles are fixed to the sides of the same, as shewn, narrow spaces being
made to intervene all round between the surfaces of the troughs and the
receptacles excepting at the points of connection, through which spaces a thin
film of water passes down the sides of the receptacles. The cross pipe K, K,
supplying thewater to these troughs through the branches k,k,k,k,is carried by
the standards L,L,L,L, which are secured to the wastewater tank Mat bottom,
and to which are also attached the bearers N, N, supporting the refrigerator.
The liquid to be cooled flows into the outer receptacle A through the pipe O
at bottom, and, after flowing up through the same, passes into the recep-
tacle B through the open passage E; in this receptacle it flows in a downward
direction and passes into the receptacle C through the pipe P at bottom, here
it again ascends and passes into the receptacle D through the channel F, and
after passing down through the latter it passes away through the pipe Q to
wherever required. The arrows serve to indicate the above-described motion
of the fluid. By this arrangement the whole of the fluid is subjected to the
cooling action of all four of the chambers. It will be evident that the fluid

page_text: may, with the same effect, be first introduced into the inner receptacle and
issue from the outer one, in which case of course the arrangement of the con-
nections would have to be reversed. If requisite, a greater or less number
of receptacles than shewn may be combined in one refrigerator, and instead
of the annular receptacles being placed concentrically, the oue within the
other, they may be arranged in any other suitable manner.
It will be evident that although in all the before described arrangements
I have spoken of the chambers into which the steam or fluid passes as being
"annular," the arrangement of parts that produces such a form being the
most practicable one, owing to the greater number of connections to be main-
tained in an air-tight condition that the adoption of any other form would
involve, nevertheless, the principle of my Invention, which is the exposure of
a thin but extended stratum of steam or fluid to the condensing or cooling
action produced by the evaporation of fluids from the outer surfaces of the
exceedingly narrow chambers or receptacles containing such steam or fluid,
may also be carried out without necessarily making the chambers of an
annular form,although, for the reasons stated, I much prefer to construct them
in that manner.
Having now described the nature of my Invention, and the best means
I am acquainted with of performing the same, I wish it to be understood that
I do not limit myself to the precise arrangements of the same as herein-before
.described with reference to the accompanying Drawings,as these mayevidently
be variously modified without departing from the nature of my Invention, nor
do I claim the use of annular chambers for the surface condensation of steam
or for the refrigeration of fluids generally, as I am well aware that various
arrangements of annular chambers have already been proposed or employed
for such purposes, but what I claim is,-
Firstly,constructingevaporative surface condensers for condensing steam of
one or more narrow annular chambers into which the steam passes and
becomes condensed by the evaporation of a thin film of water made to flow
upon both the inner and outerwalls of such annular chambers; also employing
such apparatus for the refrigeration or cooling of fluids.
Secondly, condensing steam and refrigerating or cooling fluids byexposing
thin strata of the same, contained in narrow chambers or receptacles having
very extended surfaces, to the cooling action produced by the evaporation of
thin films of water made to flow over the external surfaces of such chambers
.or receptacles.
Thirdly, the various arrangements of evaporative surface condensers and

page_text: refrigerators herein-before described with reference to the accompanying
Drawings.
Fourthly, the manner of constructing annular chambers for surface con-
densers and refrigerators, as also the method of rendering and maintaining the
joints air-tight, as herein-before described with reference to Figures 1 to 13
of the accompanying Drawings.
In witness whereof, I, the said Henry Cochrane, have hereunto set my
hand and seal, this Thirtieth day of January, in the year of our
Lord One thousand eight hundred and sixty-four.
Witness,
JOSIAH WILLIAM LISTER,
Middlesbrough-on-Tees.
HENRY COCHRANE.
OCHRANE. (L.S.)