IMPROVED APPARATUS TO BE USED FOR THE PURPOSES OF VENTILATION AND OF COMBUSTION
Year: 1880

page_text: LETTERS PATENT to William Potts, of Birmingham, in the County of Warwick,
Manufacturer and Ventilating Engineer, for an Invention of " IMPROVED
APPARATUS TO BE USED FOR THE PURPOSES OF VENTILATION AND OF
COMBUSTION."
PROVISIONAL, SPECIFICATION left by the said William Potts at the Office
of the Commissioners of Patents on the 17th April 1880.
EE
WILLIAM POTTS, of Birmingham, in the County of Warwick. IMPROVED
APPARATUS TO BE USED FOR THE PURPOSES OF VENTILATION AND OF COM-
BUSTION."
This my Invention is designed to remedy great evils that have existed relative to
burning combustibles and to ventilating attempts, both of which processes have
been unsatisfactory, but in this my Invention means are used conjointly to aid both
processes. The said processes have been unsatisfactory on the point of the outer air
being colder and denser than the air in a flue or enclosed space it has entered, and
prevented combustion going on with economy; it has checked the burning, con-
densed the smoke or vapour, and delayed the smoke's dispersion on its meeting the
external air, as it is assumed that good combustion, whether in a flue or in a lamp
that is burned in communication with the external air, should proceed by the air
entering at the bottom of burning matter, or in such a lamp, and passing from a
fire into a flue in which there is no down draught, but only an updraught, and in
such a lamp to a channel having an out draught only; the same theory is true in
regard to ventilating enclosed spaces. Warmer air requires to be drawn and con-
ducted out by a current to the outer air, free from any interruption to its outward
course.
My said Invention in relation to the improvements effected is two fold, as
concerns the two important subjects of combustion and ventilation, which are in a
sense identical, viz., that the channel for carrying off the products of combustion
will be used for removing vitiated air from enclosed spaces, or vapours from
manufacturing works, &c.; and as regards my mode of ventilating in relation to
extracting and discharging foul air, the vapours or gases are twofold on the point of
the construction of the machines used externally for the extraction and discharge

page_text: of the same matters, being different for existing buildings having chimney stacks to
the machines employed at houses to be built on my plan for using a circular flue
going through a building in lieu of a chimney stack.
The advantages of a circular flue, which by preference in houses I use of fireclay,
are great as relate to economy of space in rooms, &c., and economy of cost in
building on both points the advantage is considerable.
There are other great advantages, viz., that as the circular flue could be used for
combustion and ventilation for as many rooms placed around it as its periphery
would supply space for an opening into each room, it follows that only a seginent
of its periphery would project into each room, and this would be a slight projection,
the fire grate being low, and in front the comfort would arise, radiation of heat
reaching all parts of a room, and a view of the fire would be had by all the
inmates.
The advantages described are obtained from and by means of the said circular
flue used generally as an outlet from many rooms, and being only an up draught
channel, and also that no cold air can enter it, and its consequent freedom from
down draught, this highly important result producing brighter combustion, greater
heat, &c., consequent economy of fuel, and avoidance of condensation of smoke in
the flue, and its consequent exit into the outer air in a comparatively light state, to
be soon dispersed by the wind.
These various and great advantages are derived from the plan combining com-
bustive and ventilating results in the use of the extractor and discharger, which
are both simple in plan and powerful and certain in effect, and that a current of the
external air naturally arising in the tubular channel draws the air vapour or gas
from any place, having the said circular flue in connection with it into its current
and blows it away. It will be apparent that there is no risk of the outer air
entering a place for evident reasons, as the vane will set the entrance mouth of the
said current tube to face the wind.
I assume as additional advantages from the use of the said circular flue in
combination with the said extractors and dischargers, that the round form and
lessened size of the said smoke channel will allow in rooms of much additional
architectural beauty, that the external appearance of buildings will, by the said
form be much improved and varied, and that in the greatly diminished height of
the smoke channel, in lieu of chimney stack in connection with the uncondensed
state in which smoke will enter the atmosphere, greatly reduce the smoke nuisance
in towns, and vastly lessen that annoyance in manufacturing districts.
In ventilating railway carriages, the said extractor and discharger will not require
the vane, as the said machine will be fixed so as to face the current naturally
ineeting a train in motion.
If the said circular flue with the said extractors and dischargers are employed at
chemical works, the discharging end of the machines may be connected with
arrangements of collecting vessels, in which injurious products may be condensed
and collected so as to prevent the destructive effects produced in the neighbourhood
containing such works, as the machine referred to will enable manufacturers to very
considerably reduce the height of the chimney or discharging channel.
For the extraction and discharge of vitiated, &c., from existing houses or
buildings having an ordinary chimney stack, I employ a machine as above described
for those results, constructed so as to be employed externally, and having a natural
current of the atinospere down the extracting and discharging tube, similar to the
machines; the said machines can be used connected with a channel through the top
rail of the upper sash in windows, but is by preference used in manufacture in walls
next to the ceiling of a room, and placed in the wall's thickness; the action produces
a draught out of the internal air without a risk of the outer air entering, but the
external current tube must be fixed at least a moiety of its width external to the
wall.
The said extractors and dischargers can be most usefully employed, as will be
bereinafter described, for the extracting and purifying the air in buildings of all

page_text: kinds, carriages, railway and private, ships, outdoor lamps, mines, sewers, and all
constructions having communication with the atmosphere.
But as ventilation construed as purifying the air of enclosed spaces can be only
successfully accomplished by two processes, vic., the removal of vitiated air and the
introduction of air from without, I now describe my mode of bringing air into
rooms and spaces so as to avoid draught unpleasantly perceptible.
The channel is constructed of perforated and plain metal; it will be seen that the
outer air cannot flow directly into a room, but is made to ascend vertically, and
has to pass through three perforated surfaces; the upper one of a bead is of very fine
perforation, but in an ordinary state of weather or atmosphere the said bend being
binged is turned up, so that only two perforated surfaces have to be passed; the
entrance of air can thus be controlled; the flow inward is a very mild current, but
air is always entering. For the introduction of air from without, if at the windows,
I take out a strip of glass in the lowest sash of windows, by preferenco at the
bottom of each, and occupy the opening by the metal channel of perforated and
plain sheet metal, which allows of the air entering without perceptible draught, and
gives the power of controlling the current's force of the air entering, and also the
quantity of air admitted in the case of a direct and strong pressure of air on the
window.
The outer air enters at the perforated surface, but the plain close surface in front
of it obliges the air to take a suitable line, and to pass through the two perforated
sides before it can enter the room, which it does vertically, as the moulding in
front is a close surface.
Unless the air is strong, the bead, which is of very fine perforation and hinged to
be moveable, does not cover the outlet, but is raised up; but if the air is violently
agitated by folding the bead moulding over the outlet the entrance of air is much
limited, and the gentle diffusion of it would not annoy very sensitive persons
standing near.
This admission channel can be used in front of any opening other than that in
the glass if it is preferred to do so.
To produce an outflow of the vitiated air from an enclosed space the discharging
machines fixed externally are important in inducing an outflow of the warm air
from a room or building by means of the current of the outer air naturally flowing
down the narrow channel which is open at each end, therefore the current forined
by the outer air rushing down the narrow channel draws it into the warm air from
the room and blows it away. To prevent the outer air entering, the disc is
connected to a circular cover of the escape channels, and is turned by the air in its
passage down the tube so as to close against a stop, the cover over the opening
nearest to the end of the said tube that the air enters at, and opens the other outlet
farthest from the entrance for the passage out of the air by the current in the tube
described. The action is reversed if the wind changes, to flow in at the opposito
end of the outer current tube. The air is found to take a passage down the tube
from one or other of the entrances, but to ensure a current through the tubular
channel described, if the wind sits directly in front of the tubular channel, an
entrance is by an opening on the front line having a hinged plate to close the
nearest passage which obliges the air to take a current to the other outlet.
The constructions for air extraction specially adapted on chimneys to entirely
prevent smoke entering rooms which have a flue with down draught.
In purifying the air of carriages for railways or private use I employ the inlet
pure air channel as described, but for extracting the vitiated air from railway
carriages I use the air extractor and discharger without the vane, arranging for fixing
it in the roof of the carriage with the closed end of the inner channel to face
the front of the train; the current meeting the train forms the desired draught
to take out the vitiated air which passes out through the lamp in the carriage,
as will be explained in describing the ventilation of lamps connected with the
external air.
For the purifying the air in the lower decks or holds of ships the air extractors

page_text: and dischargers as described should be fixed on the top of a tube inside but carried
above the ship, and passing downward through the ship to the ceiling of the lowest
deck or hold it is desired to air purify. If the said tube is of adequate dimensions
all or any of those places may by an opening at the ceiling level into the said
discharging tube have the vitiated air drawn out; the external air can be adequately
supplied without perceptible draught to each place described by having a similar
tube fixed in the ship at the end opposite to the discharging tube and carried
downward to the lowest place it is desired to supply, it should have a conical cover
to keep out rain but admit air, and be carried to a convenient height above the ship.
The said inlet tube must be connected in each deck or hold to an air channel fixed
to the sides of the place at a height about one third up the side as before described.
This channel for distributing the air internally should not extend above two thirds
the length of the place to avoid a condensation of the vitiated air in its course to
the discharging tube.
Relative to purifying the state of sewers, as a general plan for extracting the
foul gases from sewers, I employ tubular channels fixed against and carried above
the highest suitable buildings at the most elevated sites in the towns; the said
tubes have bends connected to thein to join them into the sewers passing under the
footpaths, and have at the top of them the air extractor and discharger, the same
extractor and discharger as employed for buildings.
The vertical pipe between the main sewer and buildings can be applied to
preventing the escape of gases at the gratings of sewers in the foul state it does in
public ways. The pipe for the tubular current of pure air takes the place of the
curb to the footpath, having an opening next to the carriage way at each end of it.
The box having the valves and connecting this pipe with the sewer bends down
under the grating, and over the sewer it is hinged so as to lift up for cleaning out
the sewer; the volatile gases therefore meet this box passage first and are drawn up
by and into the tube current, where the oxygen in this air current will rid the gases
of dangerous power, and the gases in the condensed state will be discharged in the
chemically altered condition at a low level. Any rain entering will run away into
the sewer.
The air extractor and discharger is applicable with appliances suited to the
purpose to draw out and remove the dangerous gases existing in mines.
I use near to one of the two main shafts a ventilating shaft carried from near the
bottom of the mine to a suitable height above the earth; this extracting shaft will
be connected air tight with a circular channel around one of the main shafts near
the bottom of the nine, and this circular channel will be connected air tight with
channels running a suitable height from the floor along the drifts or ways having
holes perforated along all the lower surface to receive vapours or gases and also
having openings on the side next to all the open spaces in the mine to admit vapours
or gases, so that these collecting channels being by the plan described connected
with the external extractor and discharger a constant extract and outflow would
be proceeding to the discharging end of the extracting machino where it would bo
dispersed with the atmosphere. The other main shaft would be the inlet for air
from without and thus a constant change of air by the purifying process would be
going on.
RELATIVE TO THE VENTILATION OF LAMPS IN COMMUNICATION WITH THE
EXTERNAL AIR,
The air extractor and discharger will extract the product of combustion and
prevent the condensation, and increase the illuminating power of roof lamps in
carriages, and also in street lamps. The vane on the said extractor and discharger
is not required in railway carriage roof lamps, but it is necessary to the street
lamps. In applying the said machine to roof lamps I first close up all openings
above the burner, and then add, in a way to suit the lanp, the machine described
to form the only outlet, but I bring in air through a series of round apertures in

page_text: the roof lamp glass round the said glass below the level of the burner in the lamp,
thus preventing a cooling of the flame and condensation of the products of
combustion, increasing the light, and carrying off the vitiated air from the carriage.
In street lamps I remove or close the top and all openings above the burner and
substitute as the outlet the said extractor and discharger, making suitable openings
in the glass or elsewhere below the burner for the supply of air to it. In both
street lamps and railway carriage lamps the outlet from the inner passage to the
current tube will require to be contracted at the junction between them to prevent
the current out of the lamp being too violent, or the discharging end of the
extractor and discharger may be narrowed so as to moderate to a desired extent the
measure of the outflow.
Having before described the various beneficial, useful, and economical purposes
to which my said Invention can be applied, I will proceed by detailing the chief
features of claim.
1. As relates to the letting in of pure air from without by the removal of a portion
of the glass for ventilating purposes from windows, also the plan and the substitution
of a construction and fixing in the opening thus made of surfaces and mouldings of
metal, partly binged to move and partly perforated for the purpose of admitting
the external air without draught unpleasantly perceptible, and also the arrangement
by making the bend of fine perforation moveable to control the quantity of air
admitted and the rapidity of its current.
2. The use of a tubular flue or chimney, by preference of fire clay, constructed
with openings for the purposes above described, combustion and ventilation, and to
joint in suitable lengthis to be used in connection with the extractors and dischargers
before described when the said tubular passage is connected with more than one
place for the purposes of combustion, ventilation, or the collection of vapours or
gases in chemical or manufacturing works.
3. For the extraction and discharging of air, vapours, or gases, the construction
of machines called " extractors" and dischargers as above described, and the mode
of attaching them to the points or places they are used, together with the vane
when so required, in application to any building or construction, or flue or
chimney.
4. Also to use in the construction of the extractor and discharger, when so
required, a disc moving on a wire across from its centre, and moved by a chain or
rod fixed at any points in it so as to narrow if necessary the area of the escape
opening, and so regulate the rate of current in it, the said disc to be weighted a
little at the side opposite to where the cord or chain is attached.
5. The use of the various modes of application separately or combined, and the
various apparatus described for the burning of combustibles, the ventilation of
buildings or enclosed spaces, and lamps communicating with the external air in
ships, mines, sewers, or other places where the said modes of operating or the
apparatus can be employed.

page_text: SPECIFICATION in pursuance of the Conditions of the Letters Patent filed by
the said William Potts in the Great Seal Patent Office on the 16th October,
1880.
WILLIAM POTTS, of Birmingham, in the County of Warwick, Manufacturer and
Ventilating Engineer. "IMPROVED APPARATUS TO BE USED FOR THE PURPOSE
OF VENTILATION AND OF COMBUSTION."
This Invention is designed to remedy great evils that have existed relative to
burning combustibles and to ventilating attempts, both of which processes have
been unsatisfactory, but in this Invention means are used conjointly to aid both
processes. The said processes have been unsatisfactory on the point of the outer
air being colder and denser than the air in a flue or enclosed space has entered, and
prevented combustion going on with economy, it has checked the burning, condensed
the smoke or vapour, and delayed the smoke's dispersion on its meeting the external
air, as it is assumed that good combustion, whether in a fluc or in a lamp that is
burned in communication with the external air should proceed by the air entering
at the bottom of the burning matter, or in such a lamp, and passing from a fire
into a flue in which there is no down draught, and in such a lamp to a channel
having an out draught only; the same theory is true in regard to ventilating
enclosed spaces.
Warmer air requires to be drawn and conducted out by a current
to the outer air free from any interruption to its outward course.
I will now proceed to describe my Invention with reference to the accompanying
Sheets of Drawings, aided by the letters marked thereon, (that is to say),
Sheet 1 shews & gulley grating in longitudinal section, cross section, and plan;
also the application of apparatus B to a railway carriage door, two front elevations,
side view, section, and sectional plan of same, and elevation and section of air
admitter.
Sheet 2 shows extractor and discharger A in section, elevation, and plan; also
apparatus H for admitting air at window sashes.
Sheet 3 shews a ship in longitudinal section, sectional plan, and cross-section;
also details of extractor and discharger A, fresh air inlet U, V, and fresh air
channels W.
Sheet 4 shews gulley grating Z with disinfecting box E' and N³; also application
of extractor and discharger A to a sewer.
Sheet 5 shews application of extractor and discharger A to a mine, the upper
view being a vertical section, and the lower one a sectional plan.
Sheet & shows application of extractor and discharger A to a house, also a fire
clay flue C in elevation and sectional plan, and the apparatus for admitting air
into a room through the window sash. The lowest view on the Sheet shews
application of admitter H and discharger B to a room.
Sheet 7 shews application of extractor and discharger A to a railway carriage
roof lamp J' in section and elevation, below this is shewn its application to an
ordinary street lamp N' in elevation and plan, and to a specially constructed
lamp I'
Sheet 8 shows improved furnace for boilers with extractor and discharger to
chimney in elevation and in plan, also improved fire grate in elevation with grate
removed, also part section and detail views of grate and ash pan to a sinaller
scale.
My said Invention in relation to the improvements effected is two fold as
concerns the two important subjects of combustion and ventilation which are in a
sense identical, viz.-That the channel for carrying off the products of combustion
will be used for removing vitiated air from enclosed spaces or vapours from manu-
facturing works, &c., and as regards my mode of ventilating in relation to extracting

page_text: and discharging foul air, vapours, or gases are two fold as regards the construction
of the machines used externally for the extraction and discharge of the same
matters, being different for existing buildings having chimney stacks to the
machines employed at houses to be built on my plan for using a circular flue going
through a building in lieu of a chimney stack. The advantage of a circular or
elliptical flue,' shewn at C on Sheet 6, which by preference in houses I use
constructed of fire-clay, are great as relates to economy of space in rooms, &c., and
also of economy in the cost of building; on both points the advantage is
considerable.
There are other great advantages, viz., that as the circular or elliptical flue
could be used for combustion and ventilation for as many rooms placed around it
as its periphery would supply space for an opening into each room, it follows that
if any projection only a segment of its periphery would project into each room,
and this would be a slight projection, the fire grate being low and in front the
comfort would arise of a radiation of heat reaching all parts of a room, and a view
of the fire would be had by all the inmates.
The advantages described are obtained from and by means of the said circular
or elliptical flue C, Sheet 6, being used generally as an outlet from many rooms,
and being only an updraught channel, and also that no cold air can enter it and
its consequent freedom from down draught of air and smoke, this highly important
result producing brighter combustion, groater heat, and consequent economy of
fuel, an avoidance of condensation of smoke in the flue and its consequent exit
into the outer air in a comparatively light state, and soon to be dispersed by the
wind.
These various and great advantages are derived from the plan combining
combustive and ventilating results in the use of the extractors and dischargers,
which are both simple in plan and powerful and certain in effect. The diagrams
appended will show their construction, and that a current of the external air
naturally arising in the tubular channel draws the air vapour or gas from any
place, having the said circular or elliptical flue C in connection with it into its
current and blows it away.
It will be apparent that there is no risk of the outer air entering a place for
evident reasons, as the vane will set the entrance mouth of the said current tube to
face the wind.
I assume additional advantages from the use of the said circular or elliptical flue
in combination with the said extractors and dischargers, that the round or elliptic
form and lessened size of the said smoke channel will allow in rooms of much
additional architectural beauty, that the external appearance of buildings will by
the said form be much improved and varied, and that in the greatly diminished
height of this smoko channel, in lieu of a chimney stack in connection with the
uncondensed state in which smoke will enter the atinosphere, greatly reduce the
smoke nuisance in towns and vastly lessen that annoyance in manufacturing
districts.
If the said circular or elliptical flue with the said extractors and dischargers
are employed at chemical works, the discharging end of the machines may be
connected with arrangements of collecting vessels, in which injurious products
might be condensed and collected so as to prevent the destructive effects produced
in the neighbourhood containing such works, as the machines will enable
manufacturers to very considerably reduce the height of the chimneys or
discharging channels.
For the extraction and discharge of vitiated air, &c., from existing houses
and buildings having an ordinary chimney stack I employ a machine described B,
Sheet 6, as per diagram for those results constructed so as to be employed
externally, and having a natural current of the atmosphere through the extracting
and discharging tube; the said machine can be used connected with a channel
through the top rail of the upper sash in windows, but is by preference used in
an aperture in walls next to the ceiling and placed in the wall's thickness; the

page_text: current's action produces a draught out of the internal air without a risk of the
outer air entering, but the external tube must be fixed at least a moiety of its
width external to the wall.
The said extractors and dischargers A and B, Sheet 2, can be most usefully
employed, as will be herein after described, for the extracting and purifying the
air in buildings of all kinds, in carriages, railway and private, in ships, out door
lamps, mines, sowers, and all constructions having communication with the
atmosphere.
But as ventilation construed as purifying the air of enclosed spaces can only be
successfully accomplished by two processes, viz. :-The removal of vitiated air, and
the introduction of air from without, I now describe my mode of bringing air
into rooms and spaces, &c., so as to avoid draught unpleasantly perceptible.
To avoid disturbing walls or floors I by preference bring in the air at the windows,
and choose generally the plan of perforating by a series of suitable circular
openings, the upper sash of windows in the lower rail made from below, as shewn
at D, Sheet 6; the openings have perforated metal in them, the top perforation E
finer than the lower F, the two pieces connected by a wire, tho mode will not be
ordinarily seen, and will admit air vertically without perceptible draught. Or by
another plan I make circular openings G horizontally in a sash rail, rather more
than half way through, and meet the said openings by vertical openings within
the room, placing perforated metal in them as before described.
The channel H, Sheet 2, is constructed, as shown, of perforated and plain metal;
the outer air cannot flow directly into a room, but ascends vertically, and has to
pass through throe perforated surfaces; the upper one of the bead I is of very fine
perforation, but in ordinary states of the atmosphere the said bead being hinged
is turned up, so that only two perforated surfaces have then to be passed; the
entrance of air can thus be controlled; the flow inward is very mild, but air is
always entering.
For the introduction of air from without, if at windows, I take out a strip of
glass in the lowest sash, by preference at the bottom of each, and occupy the
opening by the metal channel constructed as H of perforated and plain sheet metal,
which allows of the air entering without perceptible draught, and gives the power
of controlling the force of the air's entrance, and also the quantity of air admitted
in the case of a strong and direct pressure of air on the window. The outer air
enters at the perforated surface J, but the plain surface in front of it obliges the
air to take the line shown by the arrows, and to pass out through the two perfo-
rated sides of the channel K before it can enter the room, which it does vertically,
as the moulding in front is a close surface. Unless the outer air is stormy, the bend I,
which is of very fine perforation, and hinged to be movcable, does not cover the
outlet at L, but is raised up; but if the air is violently agitated by folding the
bead moulding I over the outlet L the entrance of air is much limited, and the
gentle diffusion of it would not annoy a very sensitive person standing near.
This admission chaunel can be used in front of any opening other than that in
the glass if it is preferred to do so.
To produce an outflow of vitiated air from an enclosed space the extracting and
discharging machines fixed externally are important in inducing an outflow of the
warm air from a room or building by means of the current of the outer air naturally
flowing in the machines A and B down the narrow channels M which are open at
each end, therefore the current formed by the outer air rushing down the narrow
channels M draws into it the warm air from the room and blows it away. To
prevent the outer air entering an interior, the hinged disc N is connected to a
circular cover of the escape channels O, and is turned by the air in its passage
down the tube M so as to close against a stop, the cover over the O opening next
to the end of the said tube that the air enters at, and opens the other outlet
farthest from the entrance for the passage out of the air by the current in the tube
described.
The action is reversed if the wind happens to flow in at the opposite end of the

page_text: outer current tube described. The air is found to take a passage down the snid
tube from one or other of the entrances described P or Q, but to ensure a current
through the tubular channel described if the wind sets directly in front of the
tubular channel M, an entrance is at R by an opening on the front line having a
hinged plate S to close the passage from R to M which obliges the air to take a
current to the outlet Q.
The construction A is specially adapted for air extraction, and if on chimneys to
entirely prevent smoke entering rooms which have a flue with down draught.
In purifying the air in carriages for railways in private use I suitably employ
the inlet pure air channel H, Sheet 2, as described, but for extracting and
discharging the vitiated air from railway carriages I use the air extractor and
discharger A, as will be explained in describing the ventilation of lamps connected
with the external air.
For purifying the air in the lower decks or holds of ships the air extractor and
discharger A, as per diagram, Sheet 2, and description should be fixed on the top
of a tube connected to the spaces inside, but carried above the ship, and passing
downward to the ceiling of the lower deck or hold it is desired to purify. If the
said tubes T, T, Sheet 3, are of adequate dimensions all or any of these places may,
by opening at the ceiling level into the said discharging tube have the vitiated air
drawn out. The external air can be adequately supplied without perceptible
draught to each place described by having a similar tube U, V, fixed in the ship
at the opposite end to the discharging tube, (and carried downward to the lowest
place it is desired to supply, it should have a moving cover V to keep out rain but
admit air, and be carried to a convenient height above the ship. The said inlet
tube U must be connected in each deck to an air channel W fixed to the sides of
the place at a height about one third up the sides, as shewn and described in
diagrams on Sheet 3. This channel for distributing the air internally should not
extend above two thirds the length of the place to avoid a condensation of the
vitiated air on its way to the discharging tube.
As a general plan for extracting the foul gases from sewers I employ tubular
channels X, Sheet No. 4, fixed against or near and carried above the highest suitable
buildings at the most elevated sites in towns; the said tubes have bends Y, Y,
connected with them to join them into the sewers passing under the footpaths, and
have on the top of them the air extractor and discharger A.
The samo
extractor is employed for buildings on the vertical pipe between the sewer and
buildings.
For the prevention of the escape of noxious gases at the gratings to sewers in
public ways, &c., a construction Z as in diagram on Sheet No. 4 is used. It will be
seen that a long square channel A' takes the place of the kerb to the foot path,
having below it a passage going under the grating with its lower mouth over the
sewer; under tho grating B' is a box C¹ of the dimensions of the sewer with a flap
D' hinged to open downwards from the descent of the water, but being hinged a
littlo short of the centre always closes to keep out a vertical ascont of gas when
water is not passing downwards to the sewer. The gases ascending pass into the
centre compartment E' of the channel at the footpath (N° which is provided with
perforated shelves) which contains charcoal or other suitable disinfectant, then
the gases pass through the air channel F' on either side of that compartment, the
effect of which is to render the gases not offensive and to cause their discharge in
a condensed state at a low level and horizontally.
The air extractor and discharger A is applicable with appliances suited to the
purpose to draw out and remove the dangerous gases existing in mines.
.
The Inventor considers that the plans in uso of fauning the air in the main
shafts, or the costly and dangerous process of using fires in the mines to lighten
the air are fallacious, and that the awful and frequent explosions have sadly
proved his opinion to be correct. The Inventor holds that the only adequate plan
to avoid the explosion of gaseous matter in mines is to draw out the gas, as
shown by apparatus on Sheet 5, and that by placing pipes G' at the angles of the

page_text: mouths of the shafts and continuing the pipes down to communicato by bends of
the pipes H¹ to the ceilings of all the workings or vacant spaces in the mine in
connection with his said extractor and discharger A fixed on the said pipes Gl
above the top of all the external machinery, a constant extraction of the air and
gaseous matter would be going on night and day continuously from all the vacant
spaces in a mine at the highest points, and thus opon a way for the circulation of
puro air from the main shafts enclosed at bottom as low as possible.
The air extractor and discharger A will extract the products of combustion,
prevent the condonsation of them, and so increase the illuminating power of roof
lamps in carriages, as shown on Sheet No. 7, and also in street lamps, and though
on the plan described existing lamps can be used, I prefer the construction as per
diagram 1, Sheet 7. In applying the said machine to roof lamps J' in carriages I
first close up all openings above the burner, but I bring in air through the
opening K' in the centre of tho glass underneath the lamp-glass and below the
level of the burner in the lamp by means of two plates of metal L' and M¹, one
perforated the other not so, in the said opening, thus preventing a cooling of the
Hame and condensation of the products of combustion, increasing the light and
carrying off the vitiated air from the carriage and then arrange in a way to suit
the lamp, the said extractor and discharger A as diagrain on the top of the lamp
cover.
In street lamps N¹ I remove or close all openings above the burner and substitute
on the top of the lamp the said extractor and discharger A making suitable openings
in the glass or elsewhere below the burner for the supply of air to it, and placing
perforated metal 0¹ to moderate the flow of air to the burner. In both street
lamps and railway carriage roof lamps I use perforated metal plates L', M', '0', to
moderate the flow of air to the burner at the bottom of the lamp; the outlet from
within to the current tube may require to be contracted at the junction between
them to prevent the current out of the lamp being too violent, or the discharging
end of the said extractor and discharger may be narrowed by tapering it, so s
to moderate to a desired extent the measure of the outflow or perforated metal P'
fixed at the entrance end of the outer current tube to moderate the flow.
In private carriages where no roof lamp is used I employ the said machine B
fixed above the door, sec Sheet No. 1, and externally covered by a decorative
design for the removal of vitiated air. The street lamp I, as per diagram Sheet
No. 7, is constructed to employ this improved method of combustion and venti-
lation with good outline and little shadow using the above described extractor and
discharger A to carry off vapour from combustion and causi air to impinge close
on the burner.
To apply the extractor and discharger to chimney stacks containing more than
one flue I cover the top of the said stack with a construction as Q', diagram
Sheet 6, so as to concentrate the discharge from the flues into one domed extractor
and discharger A, which will thus prevent down draught into any and all of the
flues by revolving the machine to place its outer entrance to face the wind. The
form of the said cover of chimney-stack may be varied by the taste of the architect.
To avoid largely or altogether the forming of smoke and also to avoid the escape
unconsumed to the flue of much gaseous matter in burning fuel, I adopt the
following mode and shew the apparatus employed in diagram, Sheet No. 8, which
is adapted to ordinary grates; smoke consists largely of steam formed by burning
wet or damp coal; by the plan now described it will be very sparse in quantity or
of non-existance. The hydrogen gas and other matters evolved by the distillation
in the retort, which process with the fuel can only get into the fire where the
steam in its existing degree will also aid combustion.
The processes used to prepare the fuel (coal) for burning in an open fire are two,
viz., drying or dessicating, first, and then partly distilling it so as to prevent the
hydrogenous gas escaping unconsumed to the flue. For drying the coal I use a
chamber or box R' placed, as shewn, above the retort S', which have sliding covers I'
to open for the coal to fall into the grate. For the distillation of the coal the retorts

page_text: are placed under the coal box at the back of the fire-bars and in the angles of the
grate shown in diagram, with doors perforated in front to open when fuel has to be
discharged on to the fire. The retorts are about two inches above the base of the
grate to allow of fire being under them, and have openings from them for the
escape of gas to the fire. The coal box has a hinged door U', as shewn, and is
perforated at suitable parts of its surface to allow of heat entering and passing
through it, and also other openings for the escape of vapour to the flue. The
apparatus is by preference mostly of fire-clay. Having stated the processes in
preparing the fuel to avoid smoke nuisance, and utilise the whole of the fuel, I will
describe the mode of feeding the fire. An ordinary fire-grate has space for the
improved apparatus, which can be readily placed in it. When the fire needs
replenishing the opening of the retort doors I allows the hot fuel to be put on the
fire. By drawing out the valve plates V₁ of the coal box, which is over the retort,
the coal refills the retort, when distillation supplies flame to the fire, but the draught
to the Blue W is so intense as to require controlling; yet by simply using the
ratchet lever ✗' the valve Y¹ is kept open to a. desired point, the draught can be
regulated and the fire kept at any rate of burning. The intensity of the heat
produced implies economy, as rough slack can be burned, and the small space left
by the retort in the grate will be adequate to the requirement.
By this mode of using fuel very little ash will be produced, and dust avoided
greatly. The open ash pan is not used, but a drawer with perforated front Z' is
used instead of it under the grate, and the narrow openings in the vertical fire-bars
A prevents coal falling on the hearth.
The mode of burning fuel in combination with my extractor and discharger
described on the top of the flue, to prevent the entrance of cold air, will it is assumed
give every advantage derivable from scientific arrangements by using for heat all
products from the fuel, correcting the nuisances from smoke in the atmosphere or
rooms, and that arising from ash below the grate.
To apply this advantageous mode of combustion to the production of steam, with
the great additional benefit of preventing explosion of boilers from the direct action
of the fire on the surface of the metal, and also to prevent the loss of heat froin the
surface of the boiler being exposed to the outer air for stationary engines, I
construct a heat chamber B, Sheet 8, by preferenco made chiefly of fire-clay, with
double doors C² on one side for the fixing or removing of the boilers to be placed in
it. To heat the water before it goes into the boilers the water tank D' is placed
above the said heat chamber, to which its floor forms the ceiling. The said chamber
is divided by walls or partitions E' of fire brick or other suitable material, having
openings at either end alternately, as shewn, or having apertures alternately, first
at the floor and next at the ceiling, so as to allow a passage for the heat around all
parts of the boilers and prevent its rapid escape. To cause a thorough current in
the chamber I use a passage out, protected against the entrance of cold air by the
extractor and discharger. The pyrometer at the outlet from the heat chamber will
direct for the use of the valve to regulate the outflow. The steam pipe is external
to this chamber; the water is supplied to the boilers by pipes with water guages
through the ceiling of the heat chamber. The boilers F' are numerous but narrow,
so as to expose a large surface to the heat, and fixed on wheels so as to be run out
at the double door C³ of the chamber if required. The furnace G2 is placed at the
end of the said heat chamber, but sunk below the earth so that the fuel may be
easily delivered into the drying box H' above it. The floor of the drying box forms
the cover of the furnace, and has the revolving retort I below for part distillation
of the coal, which is moved by a winch and turns on each side in channel form
in the drying-box. It has two perforated surfaces J2, about half an inch distant on
its under surface to allow of gas escaping to the fire. When the firo needs
replenishing, by turning the retort to open each side alternately, the distilled hot
fuel falls in the furnace. By withdrawing the plate K² under the drying box the
coal refills the retort.
-
The means described for dessicating fuol over the furnace in connection with the

page_text: use of the extractor and discharger on the funnel will considerably lessen smoke
and oconomiso fuel. When it is considered that the said extractor and discharger
prevents cold air entering the chimney or furnace, and that consequently the draught
is very intense, that the fuel will be dried and the water heated for the boiler, that
the boilers are not exposed to the fire's action, but each offer a large surface to the
immense heat, which will be all used except the little escaping for draught, that
little or no smoke will be formed, it will be seen that the advantages aro varied and
considerable.
The whole of the said machines and appliances above described as used in this
my said Invention can be carried into practical effect by any proper workman in
iron, tin, or zinc, and it is not therefore necessary to give details or how such work
is performed.
Having now described and ascertained the nature and object of this my said
Invention, and the manner in which the same may be practically carried into effect,
nevertheless I wish to observe in conclusion that the mode that may be pursued
may be varied according to the skill, taste, or appliances of the artisan engaged in
the production according to the individual caprice, and that without affecting the
character, for instance, variation may be pursued with the external form or device;
what I claim as new and original, and desire to be secured to me by the herein.
before in part recited Letters Patent is, the application, combination, and arrange-
ment of parts forming in the whole "Improved Apparatus to be used for the
purpose of Ventilation and of Combustion" (that is to say),―
I claim the combination and arrangement of parts as relates to the letting in of
pure air from without to enclosed spaces, by the removal of a portion of the glass
for ventilating purposes from windows, and also the plan and the substitution of n
construction and the fixing of that in the opening thus made of surfaces and
mouldings of metal partly hinged to move and partly perforated, as shewn in the
diagrams, for the purpose of admitting the external air without draught unpleasantly
perceptible, and also the arrangement by making the bead of fine perforation
inoveable to control the quantity of air admitted, and the rapidity of its current.
I claim also as means for the introduction of the outer air at windows the
formation of circular openings in parts of the window sash-frames, and the fixing
of perforated metal in the said openings, as before described and illustrated.
I claim also the construction and arrangement of an inlet air channel, as
described, for fixing at other points than in window sashes, as instanced in the
description for ships.
I claim also for the extraction and discharge of air, vapours, and gases, the
constructions or machines, as shown A and B, Sheet 2, and described, with such
modifications to suit them to the points or places they are used at as circumstances
suggest or require, and the use or disuse of a vane as may be required; the effect
both constructions are designed to produce is identical, viz., the drawing out and
discharging of foul air or vapours by the external current in the machines being
adjacent to and connected with the channels from the interior, the said channels
being such construction of forms and moving parts as prevent an inflow of the
outer air, and so avoid the bad effects of condensation where an outflow is necessary,
and are applicable to lighthouses and underground railways.
1 claim also to use in the extractor and discharger A and B when required, a disc
moving on a wire across its centre and moved by a chain or cord, and fixed at any
points in it so as to narrow if necessary the area of the escape opening and regulato
the rate of current in it; the said disc to be weighted a little at the side
opposite to where the chain or cord is attached, which will pass over pulloys if
necessary.
I claim also the construction and arrangement of a single flue C, Sheet 6, tubular
and separate in form, by preference circular or elliptic, to serve for any room that
can open into it and thus avoid projecting chimney stacks, made by preference of
fire clay to joint in suitable lengths, constructed with openings for the purposes
above described of combustion and ventilation to be used in connection with the

page_text: extractors and dischargers before described A and B, which I term a one current
flue.
I claim also the use of the said extracting apparatus and means described for the
burning of combustibles or the ventilation of buildings, extracting and removing
foul air or vapour from underground railways, lighthouses, and from buildings, and
constructions generally, and lamps burned in communication with the external air,
particularly as relates to railway carriage and street gas lamps, mines, sewers, or
other places where the said modes of operating or apparatus can be employed.
I claim also the application of means to condense vapours or gases at the
discharging end of the said extractors or dischargers, also the appending at the end
of same vessels to receive vapour or gases.
I claim also the dome cover for chimney stacks having the said extractor and
discharger on its top to increase draught in and prevent down draught of cold air
into any and all of the flues in a stack.
I claim also the combination and the arrangement of parts forming the street
lamp, Sheet 7, constructed on the principle of securing good ventilation and
combustion, the glass being shaped to convey the air direct to the burner, and so
as to be warmed ere reaching it, and having two or more metal perforated surfaces
between the glass and the burner, narrowing the outlet towards the extracting and
discharging point, this not allowing any cold air to enter above the burner.
I claim also the combination and arrangement of parts forming my apparatus
for the extraction of vitiated air from houses and buildings by the use of the said
extractor and discharger with a pipe leading from the stair-case or highest point in
the interior of a building in conjunction with openings at the ceilings level from
any or all of the rooms, halls, or passages in it.
I claim the combination and arrangement of parts and apparatus for preparing
fuel for burning economically, and to avoid the smoke nuisance, and shewn on
Sheet S, being ono form of apparatus for drying and partly distilling fuel before
it passes to a grate for burning, as above described. The said apparatus is loose and
applicable to existing grates, also in grates to be manufactured when portions of
the same may be cast with the frame of the grate; also the use of a hinged valve
at the back of the arch leading to the flue and moved by a ratchet-lever so as to
keep the opening to the flue, and consequently the draught in the fire, at any
desired point; also the bonnet in front of the said arch to prevent air passing to
the flue except through or close to the fire; also the drying and partly distilling
fuel before it is burned for use in furnaces or fire places of any kind, lessening the
amount of smoke, greatly lightening it both in colour and substance.
I claim also, for the avoidance of explosion of boilers from their being placed over
a fire, the combination and arrangement of parts of a heat chamber to hold the said
boilers, and also the use in relation thereto of the means of drying and preparing
fuel for burning in connection with the use of the said extractor and discharger, as
above described and illustrated, or any mere modification that may be comprehended
in the principle of this my said Invention for "Improved Apparatus to be used for
the purpose of Ventilation and of Combustion."
In witness whereof, I, the said William Potts, have hereunto set my hand and
seal, this Fourteenth day of October, in the year of our Lord One thousand
Witness,
THOMAS KENDRICK.
WILLIAM POTTS. (L.s.)