AN IMPROVEMENT IN AND UPON CERTAIN APPARATUS ALREADY KNOWN FOR THE COMMUNICATING OF HEAT BY MEANS OF THE CIRCULATION OF A FLUID
Year: 1829

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME; we, HENRY
CRUGER PRICE and CHARLES FOX PRICE, of the City of Bristol, Ironmongers,
send greeting.
WHEREAS we did, by Petition; humbly represent to His most Excellent
Majesty King George the Fourth that, after consideration, application, and
expence, we had invented or found out "AN IMPROVEMENT IN AND UPON CERTAIN
APPARATUS ALREADY KNOWN FOR THE COMMUNICATING OF HEAT BY MEANS OF THE
CIRCULATION OF A FLUID," which Invention we believed would be of general
benefit and advantage, and that we were the true and first Inventors thereof,
and that the same had not been made or used by any person or persons whatso-.
ever.to the best of our knowledge or belief; and His said Majesty being willing
to encourage all useful inventions, was thereupon graciously pleased to grant
us. His Royal Letters Patent under the Great Seal of Great Britain, bearing
date at Westminster, the Twentieth day of August, in the. tenth year of His.
reign,. and by those Letter's Patent His said Majesty hàth, for Himself, His
heirs..and successors, given and granted unto us, the said Henry Cruger Price
and Charles Fox Price, our executors, administrators, and assigns, His especial
licence, sole privilege and authority, that we or they, by ourselves or them-
selves, or by our or their deputy or deputies, servants or agents, or such others
as we, the said Henry Cruger Price and Charles Fox Price, our executors,
administrators, and assigns, shall at any time agree with (and no others), from
time to time" and at all times during the term of years therein expressed,
shall and lawfully may make, use, exercise, and vend, within England, Wales,
and, the Town of Berwick-upon-Tweed, and also within His Majesty's Colonies
and Plantation's abroad; our said Invention, and have and enjoy the whole

page_text: profit and advantage thereof; in which said Letters Patent there is contained
a proviso obliging us, the said Henry Cruger Price and Charles Fox Price,
by an instrument in writing under our hands and seals (or under the hand and
seal of one of us) particularly to describe and ascertain the nature of our said
Invention, and in what manner the same is to be performed, and to cause
the same to be enrolled in His Majesty's High Court of Chancery within
six calendar months next and immediately after the date of the said recited
Letters Patent, as in and by the same (reference being thereunto had) will
more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Charles Fox Price, do hereby declare that the nature of our said Invention,
and the manner in which the same is to be performed, is described and
ascertained in manner following, that is to say :-
The apparatus to which our improvement relates is for the communicating
of beat to air for the purpose of warming the interior of apartments in dwell-
ing houses or shops, or manufactories, of churches and public edifices, of hot-
houses and conservatories for plants, or other buildings in which a moderate:
degree of artificial heat or warmth is required to be given to the air therein
contained, the communication of that heat being effected by means of the
circulation of hot water through a system of pipes and hollow vessels, one of:
which vessels is situated at the lower part of the aparatus, and is exposed to
the heat of fire in the manner of a boiler, in order to give heat to the water
therein contained; and other hollow vessels, which are situated at the upper
part of the apparatus, are surrounded with the air which is to be warmed by
communicating to that air a part of the heat which the contained water.
received when the same was in the boiler. The said circulation is kept up in.
that direction which will always cause the water which is heated in the boiler to
flow out from the upper part thereof through ascending pipes into the other-pipes
or vessels, which, as aforesaid, are exposed to the air; and as fast as the same.
water becomes cooled by communicating part of its heat to that air, it flows
out from the said vessels through descending pipes, and returns into the lower
part of the boiler, where it becomes heated again, and as fast as it is so heated.
it rises to the upper part of the boiler, and passes away again through the
ascending pipes to the upper hollow vessels, as before stated, so as to keep up
a continual circulation of all the water that is contained in the apparatus
through every part of the system of pipes and hollow vessels, for the water.
goes out of the boiler as soon as it is heated by the fire that is applied thereto,
and it returns back into the said boiler after it has become cooled within the
vessels which are exposed to the air that is to be warmed by the apparatus..

page_text: The said circulation results from the manner in which the said boiler and
pipes and hollow vessels are disposed; arranged, and combined, one with
another, into a system whereof that part where the fire is applied is on a
lower level than the other parts which are surrounded by the air that is to be
warmed; and the ascending and descending connecting pipes between one
part and the other of the apparatus are so arranged that the columns of water
contained in each of the said pipes respectively shall be of equal vertical
height, but nevertheless that the water constituting the column within the
boiler (and the pipes ascending from it) shall be hotter than the water consti-
tuting the column within the vessels that are exposed to the air that is to be
heated (and the pipes descending from them). In short, the apparatus must
contain two distinct columns of water, one hotter than the other, which com-
municate freely at their respective lowest levels where the boiler is situated,
and also at their highest levels, where the vessels that are exposed to the air
are situated. The two columns are of equal vertical heights or altitudes; but
the water in one column being colder (and consequently heavier) than the
hotter water in the other column will preponderate and weigh up that other
column, so as to cause motion and circulation of the water through the appa-
ratus by virtue of those alterations of specific gravity which takes place in
water or other fluids whenever they are heated or cooled. For instance, when
heat is communicated to water so as to raise its temperature, the water
expands, that is, its bulk or volume increases, and consequently the specific
gravity of the water is diminished; for any given measure of it will weigh
less than it would have weighed when the temperature was lower; or, ou the
other hand, when heat is withdrawn from water so as to lower its tempera-
ture, that water shrinks or contracts in bulk, and consequently its specific
gravity is increased. On this principle, if one of the columns of water in the
apparatus is always kept hot by the application of fire to the lowest part of it'
(that is under the boiler); and if the other column is always kept cool by the
communication of part of its heat to the air that is to be warmed (that cool-
ing taking place at the upper part of the column) then the greater specific
gravity of the cooled water in the latter column will outweigh the hotter
water in the other column so as to displace the hot water out of the boiler,
and drive it upwards through the ascending pipes into the vessels which are
exposed to the air as fast as the cooler water runs out therefrom through the
descending pipes into the boiler, and the heated water so entering those upper
vessels, being cooled in its turn, by communicating part of its heat to the
surrounding 'air, becomes heavier, and then descends, forcing up out of the
boiler a fresh quantity of water which has become licated again therein, and

page_text: consequently lightened, and thus the water in the boiler at the bottom of the
two columns being continually heated by the fire, and the water in the upper
vessels being continually cooled by warming the air with which they are sur-
rounded, a constant circulation of the water is produced through all the parts
of the apparatus, whereby that water becomes a vehicle for the conveyance
and distribution of heat from the fire to places at a distance where that heat
is required to be communicated to air. And whereas apparatus of the above
description is already known, and is not of our Invention, it is not necessary
to describe the same more minutely, what is herein-before stated being suffi-
cient to explain the kind of apparatus to which our improvement is to be
applied. And our improvement consists in a certain arrangement and combina-
tion of pipes and vessels (herein-after described) to be connected with the
upper part of the ascending pipes from the boiler (which ascending pipes con-
tain the column of heated water) in order to receive the increase which takes
place in the volume of the water that is contained in the apparatus as it
becomes heated, our improvement operating in such manner as to avoid over-
flowing by that increase, and yet to keep the boiler and the vessels which are
exposed to the air which is to be warmed (as well as the ascending and
descending pipes connecting. between the same) always full of water. And
further, our improvement consists in constructing the aforesaid vessels which
are exposed to the air that is to be warmed in a particular manner (herein-
after described) with several cylindrical vessels of different diameters, which
are put one within another in pairs, the upper and lower edges of each pair
being joined together, in order that the space left vacant between the two.
cylinders may form a vessel to contain the hot water. A series of such. cylin-
drical vessels are disposed one within another, leaving narrow cylindrical spaces
between them for the passage of the air that is to be warmed by the hot
water which is contained within the vessels, consequently the said air will be
exposed or spread out in thin layers, which are situated between extensive
surfaces of the vessels containing the hot water, and, conversely, the hot water
so contained will be spread out in thin layers between the said extensive sur-
faces that the vessels expose to the air, and that air is caused to ascend in a
continuous current through the narrow cylindrical spaces allotted for it between
the said cylindrical vessels, at the same time that the hot water flows down-
wards through the interior of the cylindrical vessels, whereby the heat of the
water will be rapidly and completely communicated to the air.. And for the
full explanation of our improvements w have hereunto annexed a Drawing
which represents so much of an apparatus for the communicating of heat to
air by means of the circulation of hot water through the apparatus, as is requi

page_text: site for the full explanation of our improvement, and the adaptation thereof to
the apparatus already known.
Figure 1 is an elevation of the apparatus with our improvement.
Figures 2, 8, and 4 are horizontal sections of what we term our water stovė,
being our aforesaid series of vessels one within another, by which the heat
is communicated. from the hot water to the air; and Figure 5 is a vertical
section of the same stove. The same letters of reference are used to denote
the same parts in all the Figures. A represents the boiler, which is of the
kind commonly used for steam engines, and the only difference in the use of
it is, that it is quite filled with water. The boiler is heated by applying fire to
it in any of the modes in use for steam boilers; but the furnace is much
smaller in proportion to the boiler than is usual in steam boilers: The con
struction of the boiler forming no part of our Invention need not be further
described. B is an ascending pipe joined to the upper part of the boiler to
convey the hot water therefrom up to the cylindrical vessel C. The ascending
pipe B is no part of our Invention. The vessel C, with the pipes and vessels
marked D, E, F, G, H, I, and K, we term our safety reservoir; and we claim
the whole thereof as part of our Invention. The cylindrical vessel C is of
such size' as will facilitate the union of those pipes with it, and it also serves
as a reservoir which contains an extra quantity of water beyond what would
be absolutely necessary to the performance of the apparatus; and thereby
allows hot water to be drawn off from the apparatus (when required for any
useful purpose) without interrupting the operation of the apparatus. D is a
pipe joined to the top of the vessel C; and; to the bottom of the upper vessel. E,
in order to convey the increased and superfluous quantity of water (whether
arising from the expansion of the water by heat or otherwise) from C'into Er
The pipe D is curved or looped. down. and up again to form an inverted syphon
which will prevent the circulation of water that might otherwise, take place
between C and E, in consequence of the water contained in C (which is the
lowest) being hotter than that contained in E' (which is higher). E is a vessel
in form of a frustrum of a cone, open at top,. and the pipe D joins to it-at
bottom;
it receives the water that may proceed from-C,, in consequence of the
increase of the volume of the water contained in the apparatus' when it becomes
heated. As the vessel E is provided to allow for that expansion, its capacity.
should be made suitable to the increase of bulk consequent upon the applica-
tion of heat. When the fluid employed is water, the capacity of the vessel E
should be one twentieth part of. the quantity of water contained in all- the:
other parts of the apparatus; because water at the mean temperature of. 52
degrees of Falirenheit expands about one twentieth of its volume, when it

page_text: becomes heated to 212 degrees, or the boiling point. The vessel E is made
conical, in order that as the water rises within it the extent of surface it
exposes to the atmosphere may be diminished, and the evaporation propor-
tionally lessened. F is a cylindrical vessel, within which the conical vessel E
is contained, as it were, within a case. The vessel F is open at top, and its
use is to receive such part of the water as may overflow the top of E in conse
quence of the generation of vapour in the boiler, or any other cause: The
waste of water from the apparatus, whether by evaporation or by being
withdrawn for usual purposes, or from other causes, may also be supplied by.
pouring water into the vessel F, and G is a pipe descending from F to C, with
a stopcock in it at E to let down the water from F into C. I is a short pipe
joined to the lower part of the loop in the pipe D, and to the pipe G, where it
joins to the top of the vessel C. It has a stopcock K in it. When the cock
K is opened, it allows the loop of D to empty itself of water, which might
otherwise obstruct the escape of the air from the apparatus when it is to be
filled preparatory to working. L is a pipe from the bottom of the vessel C to
the bottom of our stove M. 'The pipe L is no part of our Invention.
M (see also Figures 2, 3, 4, and 5,) is our stove, which we do claim as part
of our Invention. N is a pipe descending from the bottom of the stove M to
the bottom of the boiler A: it serves to conduct the water down from the
stove M (as it becomes cooled therein) to the boiler that it may be heated
again. The pipe N we do not claim as our Invention. The vessel C should
never be entirely empty, and to ascertain the height of the water within it a
small vessels is joined at the lower part of it by the pipe r and cock t to the
bottom of the vessel C; therefore, when the cock t is opened (the cocks H or K
being also opened to establish a free communication with the atmosphere) the
water will rise within the vessel s to the same height as it stands within C.
The vessels is open at top, and that top is on a higher level than the top of C.
s may be made of glass, to see the height of the water within it. The parts
r, s, t, we do not claim as part of our Invention. The stove M is made of
concentric cylinders, placed one within the other, leaving narrow spaces
between the cylinders, which are united in pairs at top and at bottom, so
that the space left between each pair will serve as a vessel to contain
water, as is shewn by the coloured spaces d, e, in Figures 3 and 5. The
spaces or intervals f, f, f, between the several cylinders c, d, e, that contain
the water, are left vacant for the passage of the air that is to be warmed
by the hot water that is contained within the vessels c, d, e. The cylin
drical vessels d, e, of the stove are each composed of two cylinders of
metal, which enter one within the other, leaving a space of about two inches

page_text: wide for water between the two cylinders, and they are united to each other
by flanges at top and bottom of each, viz, the flange at the bottom of the
smallest or interior cylinder projects outwards from the base thereof, whilst the
lowest flange of the larger or external cylinder projects inwards therefrom,
and the under surface of the latter flange applies upon the upper surface of
the before-mentioned flange; suitable packing is interposed between the
flanges, and they are united by screws put upwards through the lowest flange,
and screwed into the other. In like manner the flange at the top of the inner
cylinder projects outwards, whilst the upper flange of the outward cylinder
projects inwards, but those upper flanges fit one into the other to form one
plane, the outside circumference of the flange of the inner cylinder being of
the same size and figure as the inside circumference of the flange of the exterior
cylinder, and the crack. between those two circumferences is covered by a flat
circular ring applied over the top surface of the two flanges, with suitable.
packing under the ring, which is fastened down by screws put down through
the ring, and tapped into the flanges. Note.-It is obvious that in order to
put the cylinders together the lower flange of the outer cylinder must be large
enough withinside to drop over the upper flange of the inner cylinder, but ears
may project within the interior circle of the said lower flange of the outer
cylinder to receive the screws, and corresponding indentations being made in
the exterior edge of the upper flange of the inner cylinder, will allow one.
cylinder to drop over the other; also the interior of the upper flange of the
outer cylinder must have ears projecting inwards to fill up the said indenta-
tions. Each of the vessels so formed of two cylinders has two necks projecting
from it, viz, one at the bottom, projecting downwards to connect with the
branches m, m, of the pipe N to convey the water away from the stove,
and the other neck projecting upwards from the top to connect with the
branches x, x, in order to introduce the hot water into the vessel. For this
purpose the pipe L is joined to the bottom of the large pipe C, which stands
up in the centre of the smallest of the vessels. That large pipe may be con-
sidered as a continuation of the pipe L, only enlarged in diameter, to form a
small vessel, and expose more surface. An interval is left all round it for the
passage of the air that is to be heated, and at the top of the vessel C the
branch a,, is joined to connect with the upper necks of the concentric vessels
d and e, in order to introduce the hot water freely and equally into both them.
Note. The upper neck of each vessel, where the hot water is introduced into
it, should be situated at that part of its interior capacity which is the most
remote from the lower neck by which the same water makes its exit from the
same vessel, in order that the water may be compelled to pass through every
part of the interior of the vessel. The bottom of the stove is raised up from

page_text: the floor of the apartment in which the stove is placed by supports, in order to
admit the external air beneath the bottom, that it may pass freely up into the
spacės left vacant for its passage upwards between the several water vessels
c, d, e. The top of the stove is a dome a, covering all the cylindrical vessels
of which the stove is composed, and receiving all the air that rises up through
the spaces ffff, between them. At the top of the dome a is a turning
register of the same kind' as is usually applied in other air stoves: that register
serves to regulate the exit of the warm air from the stove, according to the
quantity that is required to be discharged into the place where the stove is
situated. h is a small tube joined at the highest part of the top branch ï, x,
which connects the three vessel's c, d, e. The tube h passes up through the
centre of the turning knob of the register at the top of the dome a, and has a
small air-cock m at the top, which is open to allow the air to escape from the
spaces c, d, e; when they are to be first filled' with water, but when they become
full the air-cock m is to be shut. To fill the apparatus for action, all the stop-
cocks H, K, t, and m must be opened, and water being introduced into the
upper vessel F, it will flow through the pipe G and cock H into the vessel' C, and
from thence by the pipes B, L, and N it will run down and fill the boiler A
and the stove M until every part thereof is full. When the water begins to
issue at the cock m, that cock must be closed, and also when the height of the
water in the transparent or other vessel's indicates that the vessel C is full to
the top, all the other cocks H, K, and t must be shut. Note.-This mode of
filling the apparatus from the vessel F is that which may be commonly
practised, though it is by no means essential that the water should be intro-
duced at F. If convenience requires, the water may be introduced (either by
a pump or by a pipe from an elevated' reservoir) into any part of the apparatus,
even into the boiler A, the only condition being that the whole apparatus' shall
be completely filled up to the level of the top of the vessel C. The fire is then
to be lighted beneath the boiler A, and as the water within it becomes heated
(and consequently becomes specifically lighter than the water in the other parts
which has not been heated) the circulation will begin by the colder and
heavier water in the descending pipe L, N, overbalancing the hotter and
lighter water in the ascending pipe B; and therefore the colder water will force
its way into the lower part of the boiler A, and displace and force therefrom a
corresponding quantity of hot water up the ascending pipe B, and' into the
vessel C. It is obvious that a corresponding quantity of water will at the same
țime run down the descending pipe L, and pass through the stove M, where it
will communicate part of its heat to the air that is contained in the spaces
ffff, and the water thus becoming cooled (and consequently heavier) will
descend through the descending pipe N into the bottom of the boiler, forcing

page_text: up a like quantity of heated water by the ascending pipe B, and so the circu-
lation will go on.
The fire under the boiler continues giving heat continually
to the water that is within it, and the stove always communicates part of the
heat of the contained water to the air that is passing through it, and which
surrounds it. Hence the difference of specific gravity which causes the
circulation is continually kept up so long as the fire is continued, and the
apparatus kept at work. It it obvious that the heat given to the water should
never be accumulated so much as to produce steam in the boiler. Note.-The
ascending pipe B and the vessel C should be covered with wrappers of non-
conducting substance, to avoid loss of heat by radiation and contact with the-
air, because the ascending column of water in A, B, C, must be kept hot,
whilst that in L, M, N, is cooled. If more convenient, the ascending pipe B.
may be carried up within the chimney of the furnace for the boiler. The
above apparatus is represented with only two of our stoves M, but the same.
boiler and pipes, and our safety reservoir (consisting of the vessel C, with the;
pipes and vessels marked, D, E, F, G, H, I, K,) may supply several of our
stoves, situated either in different places, or together in the same place,
according to the distribution of heat and heated air that is required to be
effected by the apparatus. It is advisable to place the stoves M on a level
as much higher than the boiler A as convenience will allow, because the
circulation will be the more rapid, and consequently the communicating of heat
will be more effectual. The water which has passed through one of our stoves.
may afterwards be conducted through another stove, as is shewn by the Draw-
ing, so as to serve both. The dimensions of the apparatus, and the form and
disposition of the several pipes and vessels, must be adapted according to the
situation in which the apparatus is to be fixed, and the space, which is to be
heated thereby. Few situations being alike in all respects, no rule can be
laid down for dimensions, but the same must be left to the judgment of the
artificer who is to construct the same, and he must adapt it according to local
circumstances of each particular case. And as the materials of which the parts
of the apparatus are to be composed, we prefer cast iron for the large pipes.
and reservoirs and for the stove, and wrought iron for the boiler. The smaller
pipes and cocks may be of copper and brass; and although the vessels of
which the stove is composed are stated to be cylindrical, they may be made
square, or of any other form that is preferred for giving them an ornamental
appearance.
In witness whereof, I, the said Charles Fox Price, have hereunto set
my hand and seal, the Seventeenth day of February, in the year of
our Lord One thousand eight hundred and thirty
CHARLES FOX (L.S.) PRICE.

page_text: AND BE IT REMEMBERED, that on the same Seventeenth day of
February, in the year above mentioned, the aforesaid Charles Fox Price
came before our Lord the King in His Chancery; and acknowledged the
Specification aforesaid, and all and every thing therein contained, in form
above written. And also the Specification aforesaid was stamped according
to the tenor' of the Statute in that case made and provided.
Inrolled the Twentieth day of February, in the year above written.