IMPROVEMENTS IN THE VENTILATION AND HEATING OF BUILDINGS AND IN APPLIANCES THEREFOR
Year: 1877

page_text: LETTERS PATENT to Francis Thomas Bond, of Gloucester, in the County
<<
of Gloucester, Doctor of Medicine, for the Invention of IMPROVEMENTS
IN THE VENTILATION AND HEATING OF BUILDINGS AND IN APPLIANCES
THEREFOR"
Sealed the 16th April 1878, and dated the 25th October 1877.
PROVISIONAL SPECIFICATION left by the said Francis Thomas Bond at
the Office of the Commissioners of Patents on the 25th October 1877.
FRANCIS THOMAS BOND, of Gloucester, in the County of Gloucester, Doctor
of Medicine. "IMPROVEMENTS IN THE VENTILATION AND HEATING OF BUILDINGS
AND IN THE APPLIANCES THEREFOR." .
This Invention refers to improvements in two methods of warming and venti-
lating buildings, which are described in a Provisional Specification which I deposited
at the Office of the Commissioners of Patents on the 8th of December 1876.
The first of these describes a method of bringing fresh air into a building by
means of a tubular bracket, which bracket may also be made to serve the purpose of
a gas bracket by carrying a gas pipe through its interior and so arranging the
burner that the air with which it shall be supplied shall be drawn through the tube
from the outside of the building. Since the filing of the said Specification I have
found that it is more convenient to introduce fresh air in connection with a gas
bracket by suspending over the burner at a suitable distance a shade of glass or
other appropriate material, terminating above in a short straight chimney. I connect
this chimney, just above its junction with the shade, with a cylindrical tube which
opens into it at a right angle, and the other end of which is fixed in an aperture in
the wall, through which fresh air can pass into the tube and chimney either directly
from the outside, or by the medium of a passage in the wall from the space above
the ceiling or below the floor. When the gas burner of the bracket is lighted the
heated air ascending into the shade and passing up through the chimney drags up
at the same time a current of fresh air through the tube, according to a well-known

page_text: principle, which is illustrated in the apparatus know as Sprengel's air pump, and
in other familiar appliances. When the gas is not burning the tube and chimney
serve to introduce fresh air into the building at an ordinary temperature; but when
the burner is lighted the fresh air as it enters the tube and passes up the chimney
into the building becomes mixed with the products of combustion, and while it
dilutes them is at the same time itself warmed. The force of the current in the
tube may be regulated by means of a throttle valve placed in it.
My. second improvement refers to a form of ventilating stove, which I have
described in the latter part of the same Specification, as consisting of a cylinder in
which gas is burned so as to heat fresh air which is introduced into the building
through the cylinder by means of a cone of copper or other suitable metal, and and
having on the outside of it a series of small tubes through which the products of
combustion pass down to an annular chamber, and thence by a pipe connected with
this chamber into the outer air. I have found that this arrangement is defective
in use by reason of the fact that there is no means of regulating the force of the
draught through the stove so as to meet the varying pressure to which the out-
going products of combustion may be exposed, especially from the influence of a
strong wind outside the building, or of a suction current from within, either of
which may reverse the current of the products of combustion and cause them to
pass back into the building. In order to obviate this defect I attach an outlet pipe
to the upper part of the stove, and I connect this outlet with that at the bottom of
the stove by an intermediate pipe, so that the products of combustion may either
pass out from the stove directly through the upper outlet, or after passing down the
series of small pipes on the outside of the cylinder by the aperture in the annular
chamber, as before described. In the upper aperture I place a throttle valve, by
means of which the direction of the current of the products of combustion in the
stove may be regulated at will, for if the valve is open they will escape through the
upper aperture, & if it is closed they will be compelled to pass down the series of
small tubes into the annular chamber and out by the lower aperture. By this means
the force of the draught through the stove can be regulated at will.
I have also found that inconvenience and even danger may arise in lighting this
stove, if by accident the gas is turned on for a short time before the light is
applied to the ring of burners, whence an explosion may occur from the coal gas
becoming mixed with atmospheric air in the stove. In order to obviate this defect
I connect a small pipe with the hole in the plug of the tap by which the gas is turned
on to the burner, and which tap I fix just outside the stove in such a way that the
gas can pass through the tap into the pipe without necessarily passing into the ring
of jets inside the stove. The small pipe is so arranged that it moves with the plug
of the tap, which is, indeed, operated by moving the pipe, and its free end is per-
forated to allow of gas issuing from it in a small jet, which can be regulated or
extinguished by means of a tap on the pipe. A small aperture in the cylinder
allows the pipe and jet to be moved into the interior of the stove, and the form of
the pipe, which is curved for the purpose, and its relation to the main tap, are so
arranged that as the jet of ignited gas at the end of the pipe approaches the ring of
-burners inside the stove it turns on the gas and at the same time ignites it as it
issues from them. It is thus impossible for an explosion to occur, as the gas is not
turned on to the burner until the movable pipe and jet connected with the tap are
in such a position as to ignite it.
Another improvement which I have made in the said stove is to affix to the inlet
of the fresh air pipe at the base of the cone a box or chamber containing cotton
wool or other similar material, by means of which the incoming air may be purified
from soot, dust, and other suspended impurities which it may bring with it, thus
obviating the disagreeable smell which such matters are apt to produce when they
come in contact with heated surfaces.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent and of
an Order of the Lord Chancellor filed by the said Francis Thomas Bond in
the Great Seal Patent Office on the 7th May 1878.
FRANCIS THOMAS BOND, of Gloucester, in the County of Gloucester, Doctor of
Medicine. "IMPROVEMENTS IN THE VENTILATION AND HEATING OF BUILDINGS,
AND IN APPLIANCES THEREFOR.'
"
This Invention has for its object improvements in warming and ventilating
buildings.
My first improvement relates to an improved method of bringing hot air into a
building by means of a tubular bracket, which bracket may also be made to serve
the purpose of a gas bracket by carrying a gas pipe through its interior, and so
arranging the burner that the air with which it shall be supplied shall be drawn
through a tube from the outside of the building. In order to effect this object I
introduce fresh air in connection with a gas bracket by suspending over the burner,
at any suitable distance, a shade made either of glass or other suitable material,
terminating above either in a short, straight, or slightly conical chimney, which is
connected just above the point of its termination in the shade with a cylindrical
tube, one end of which opens into it at right angles, while the other end thereof is
fixed into an aperture in the wall through which fresh air can pass into the tube
and chimney, either from the outside or by the medium of a passage in the wall,
from the space above the ceiling or below the floor. When the gas burner of the
bracket is lighted the heated air ascending into the shade passes up through the
chimney, and simultaneously introduces a current of fresh air through the tube,
according to a well-known principle. When the gas is not burning the tube and
chimney serve to introduce fresh air into the building at an ordinary temperature ;
but when the burner is lighted the fresh air as it enters the tube and passes up the
chimney into the room becomes mixed up with the products of combustion, and is
thus warmed. The force of the currrnt in the tube is regulated by means of a
suitable throttle valve or its equivalent with which the same is furnished.
My second improvement refers to an improved form of ventilating stove, which
in a Provisional Specification, No. 4752, of 8th December 1876, I have described as
consisting of a metal cylinder in which gas is burned, so as to heat fresh air which
is introduced through the cylinder by means of a cone of copper or other suitable
metal, and having on the outside of it a series of tubes through which the products
of combustion pass down to an annular chamber, and thence by a pipe connected
with this chamber into the outer air. Since filing the said Specification I have
found that this arrangement is defective in use, by reason of the fact that there is
no means of regulating the force of the draught through that portion of the stove
in which combustion takes place, so as to meet the varying conditions of pressure
to which the outgoing products of combustion may be exposed, especially from the
influence of a strong wind outside the building, or of a source of suction, such as a
fire in an adjoining room within it, either of which influences may reverse the
current of the products of combustion, and cause them to pass back into the building
in consequence of their being over cooled by passing down the outer series of tubes.
In order to obviate this defect I attach an additional outlet pipe to the upper part
of the stove, and I connect this outlet with that at the bottom of the stove by an
intermediate pipe, so that the products of combustion may either pass out from the
stove directly through the upper outlet, or by the aperture in the annular chamber,
after passing down the series of tubes on the outside of the cylinder, as before
described. In the upper aperture I place a throttle valve, by means of which the
direction of the current of the products of combustion may be regulated at will, for
if the valve is open they will escape through the upper aperture, but if it be closed
they will be compelled to pass down through the series of tubes into the annular

page_text: .
chamber, and out by the lower aperture. By this means the force of the draught
can be regulated at will.
I have also found that danger may arise in lighting the stove above referred to, if
by accident the gas should happen to be turned on for a short time before a light
is applied to the ring of burners, whence an explosion may occur from the coal gas
becoming mixed with atmospheric air in the stove. In order to obviate this defect I
connect a small pipe to the gasway in the plug of the tap by which the gas is
turned on to the burners, and which tap I fix just outside the stove in such a way
that gas can pass through the tap into the pipe without necessarily passing into the
ring of jets inside the stove. The small pipe is so arranged that it moves with the
plug of the tap, which is indeed operated by moving the pipe, and its free end is
perforated so as to allow the gas to issue from it in a small jet, which can be
regulated or extinguished by means of a tap on the pipe. A small aperture in the
cylinder allows the pipe and jet to be moved into the interior of the stove; and
the form of the pipe, which is curved for the purpose, and also its relation to the
main tap are so arranged that as the jet of ignited gas at the end of the pipe
approaches the ring of burners inside the stove it turns on the gas, and at the same
time ignites it as it issues from them. It is thus impossible for an explosion to
occur if the burner is lighted by the jet of the movable pipe, as the gas is not turned
on to the burner until the movable pipe and jet, which is connected with the tap,
is put into such a position as to ignite it.
Another improvement which I have made in the said stove is to affix to the
inlet of the fresh air pipe at the base of the cone a box or chamber containing
cotton wool or other similar material, by means of which the incoming air may be
purified from soot, dust, and other suspended impurities which it may bring with it,
thus obviating the disagreeable smell which such matters are apt to produce when
they come into contact with heated surfaces.
I will now proceed to describe in detail the appliances which I employ for the pur-
poses above specified, and which are illustrated in the accompanying Drawings. In the
said Drawings, Figure 5 is a sectional representation of the tubular bracket above
described, in which A is a tube which is connected at right angles to a vertical
chimney B. The tube and chimney may be made of metal, glass, or earthenware.
To the bottom of the chimney is attached a glass shade C for the purpose of
collecting the heated gases which arise from the flame of the gas bracket over which
the chimney is to be placed, and of directing them into the chimney B. The tube
A is attached telescopically, or in any other convenient manner, to a second tube E
open at both ends, one of such ends being fixed in an aperture made for the purpose
through the wall to which the gas bracket is attached, and by this means communi-
cation is effected with the outer air. In the tube A is placed a throttle valve D,
or other suitable contrivance, for the purpose of regulating the passage of air there-
through.
As I have before stated, the heated air, whilst passing up through the chimney B,
will draw in a stream of fresh air through the tube A, which will mix with it as it
passes out of the upper aperture of the chimney, thereby cooling it, and diluting the
offensive emanations which it contains. This result will however only take place
if there be an outlet for the escape of air from the room in which the bracket is
placed, such as a fire-place or an eject provided specially for the purpose. If there
be no such outlet the tube will then become one, and instead of being the medium
for introducing fresh air, it will serve for the escape of a portion of the heated air
rising through the chimney. It will thus be seen that the bracket will act either
as an inlet or an outlet, according to the conditions which are present in the room
in which it is fixed.
In the same Drawings Figure 1 is an elevation of my ventilating stove; Figure 2
is a vertical section of the same made through the centre; Figure 3 is a general
plan, and Figure 4 a sectional plan made in the plane a, b.
The alphabetical letters in the said Figures refer in each case to corresponding

page_text: details. Of these details A is a metal cylinder which may either be made of sheet
iron or of any other suitable material. The proportions of this cylinder are not
material, but it will be found generally convenient for its height to be about twice
its diameter. The lower margin of this cylinder is free, and forms the aperture by
which air is admitted into the interior of the stove for the purposes of combustion.
The upper margin of this cylinder is connected in an air-tight manner with the
upper margin of the hollow cone G. This cone may be made of any suitable metal,
but I prefer to make it of sheet copper, because the high conducting power of that
metal renders it very appropriate for the purpose. The lower margin of the cone
ends in a tube H, which may either terminate by a free aperture a little below the
lower margin of the cylinder, or be connected with the outer air by a prolongation
carried downward through the floor or through an adjoining wall, as may be most
convenient.
Inside the cylinder, and encirling the cone near its lower part, is a perforated
gas pipe K, Figures 3 and 5, which, when supplied with gas and ignited, forms a
ring of gas jets. The aperture in the pipe from which these jets proceed should
not be more than half an inch apart, so that when one jet is ignited the flame may
travel all round the ring. The ring is connected with the gas main by means of
the horizontal pipe L, Figures 1 and 3, which passes through an aperture in the
cylinder A. On this pipe, just outside the cylinder A, is placed a stop-cock, the
thumb piece of the plug of which is replaced by a piece of smaller piping N, the
interior of which is connected with the gasway of the plug by a hole bored vertically
down the plug into the gasway into which the pipe is fixed. On this pipe is fixed
a small stop-cock P, Figures 1 and 3, and the pipe itself is of sufficient length and so
curved that when it moves on the plug as its axis towards the cylinder, the pipe
approaches a small aperture 0 in the side of the cylinder A, through which it passes
until it comes in contact with the ring of the burners. The relation of this pipe to
the cylinder A and ring of burners in these two positions, and the course which it
takes, are shewn in Figures 3 and 4.
The plug of the tap M has a groove running horizontally half way round it,
connecting the two ends of the gasway with one another on the side of the
plug which is away from the stove when the
gas turned off, so that when the
jet pipe is in the position indicated in Figure 3, though the gas cannot pass to the
burner, it can pass through the groove round the plug into the vertical aperture in
its centre, and so into the pipe N. Hence, if when the jet pipe is in this latter
position the tap P be opened, and the jet of gas which issues from the end of the
pipe N be ignited, and the pipe be rotated on the plug so as to bring the jet towards
the ring, the gasway through the plug will be opened, the gas will be turned on to
the burner, and the jets in the latter will be ignited by the jet of the pipe, which
will by this time have approached sufficiently near to do so. By this means the jet
pipe not only serves as a convenient means of lighting the ring of burners, but also
prevents the gas from being turned on until the light is applied to the ring, thus
obviating the danger of explosion which might occur if the gas were turned on by
an ordinary tap some little time before a light were applied.
On the outside of the cylinder are fixed a series of metallic pipes B, which may
vary in number and size, according to the quantity of gas which it is proposed to
burn for the purpose of heating the stove, but I have found that ten pipes, bearing
the proportion to the cylinder in regard to size which is indicated in the Drawings,
is the most generally convenient arrangement.
For the purpose of giving ornamental effect to the stove these pipes may be
modelled in the shape of hollow pillars, with capitals and pediments, or any other
suitable design. Each of these pipes terminates above by a slight lateral prolongation
on one side of the capital, which when adjusted to a corresponding aperture in the
upper part of the cylinder, and fixed in this position in an air-tight manner, brings
the interior of the pipe into connection at its upper end with the interior of the
cylinder. The lower aperture of each pipe is fixed in a similar way to the upper

page_text: surface of an annular metallic chamber C, with the interior of which the pipes B are
thus brought into communication.
The pipes and chamber may be made of any metal, but I prefer to make the
pipes of copper or brass and the chamber of zinc or iron, both for the sake of
appearance, heat-giving effect, and convenience of manufacture. To the circum-
ference of the annular chamber is attached the flue D for carrying off the products
of combustion. This flue is also connected by a second junction at E with the
interior of the cylinder at its upper part. In this connecting pipe is placed an
ordinary throttle valve F, by means of which the passage through this junction pipe
can be opened or closed at will.
In the side of the cylinder may be fixed a piece of glass or mica Q for the purpose
of allowing the ring of jets to be seen, and of thus more easily regulating their com-
bustion. At R is placed a tap for the purpose of drawing off any water which may
accumulate in the annular chamber from the condensation of the vapours of com-
bustion in it or in the flue or tubes.
The operation of the stove will now be evident from the description of its several
parts given above, and from the course of the arrows in Figure 2, which indicates
the direction in which the contents of heated air will pass. If the ring of jets be
lighted air will be drawn up into the interior of the cylinder to support combustion;
it then becomes heated, and is carried in company with the products of combustion
to the upper part of the space between the cone and cylinder. If the throttle valve
F be open the heated gases will pass at once into the flue by the junction pipe E,
which will thus become heated, and a steady flow of air through the stove can be
thereby readily established. When this result has been accomplished the valve F
may be closed, and the heated gases will be compelled to pass at once into the tubes
B, and so down into the annular chamber C, and thence into the flue D. In passing
through this lengthened course the heated gases are brought into contact with a
large surface of metal, to which they give up the greater part of their heat, which is
communicated by the metal to the air around it. By this means a large economy
of the heat produced by the combustion of the gas is effected and applied to warming
purposes. The heated gases as they pass up the cylinder give off a great deal of
their heat to the copper cone, which, in its turn, heats the fresh air supplied to the
pipe at its lower aperture; hence the stove not only heats the air of the room in
which it is placed by the large amount of surface exposed by the cylinder, tubes,
annular chamber, and flue, but also by the current of heated fresh air which escapes
from the mouth of the cone.
When it is desirable to purify the air thus brought into the cone from dust and
other impurities mechanically suspended in it, I attach to the tube at the lower
aperture of the cone a cylindrical metallic vessel S, divided into two chambers by a
perforated diaphragm T. In the upper chamber I place cotton wool loosely com-
pressed, so as to act as a filter of the air which passes through it. This vessel is so
made that it may be easily slipped on to the tube at the lower end of the cone, and
it is divided into two parts transversely just above the diaphragm, so that it may be
opened for introducing and removing the cotton wool.
The stove, constructed as above described, is raised a few inches from the floor by
means of legs, so as to allow free access of air to the lower margin of the cylinder.
Having now particularly described and ascertained the nature of my said improve-
ments, and the manner of carrying the same into operation, I would have it understood
that what I claim is,-
1°. The improved method of introducing fresh air in connection with a gas bracket
by means of a glass or other suitable shade connected with a cylindrical tube, and
otherwise arranged, substantially as herein-before described and illustrated.
2°. The regulating the force of the draught through that portion of the stove,
herein-before described, in which combustion takes place by means of an additional
outlet and intermediate pipe, provided with a throttle valve or its equivalent, sub-
stantially as herein-before described and illustrated.

page_text: 3°. The improved method of preventing explosion in such stove by connecting a
small pipe to the gasway in the plug of the gas tap, arranged substantially in the
manner herein-before set forth.
4°. The improved method of purifying the incoming air introduced through such
stove from soot and other suspended impurities by means of a chamber containing
cotton wool or its equivalent affixed to the inlet of the fresh air pipe at the base of
the cone, substantially as herein-before set forth.
In witness whereof, I, the said Francis Thomas Bond, have hereunto set
my hand and seal, this Third day of May, in the year of our Lord One
thousand eight hundred and seventy-eight.
FRANCIS THOMAS BOND. (L.S.)