IMPROVEMENTS IN WARMING APARTMENTS, AND IN STOVES, GRATES, RANGES, AND OTHER FIRE-PLACES, AND THE FLUES CONNECTED THEREWITH
Year: 1876

page_text: LETTERS PATENT to Thomas Brown Dalziel, of Croydon, in the County of
Surrey, Gentleman, for the Invention of "IMPROVEMENTS IN WARMING
APARTMENTS, AND IN STOVES, GRATES, RANGES, AND OTHER FIRE-PLACES, AND
THE FLUES CONNECTED THEREWITH."
Sealed the 20th March 1877; and dated the 29th September 1876.
PROVISIONAL SPECIFICATION left by the said Thomas Brown Dalziel at
the Office of the Commissioners of Patents on the 29th September 1876.
THOMAS BROWN DALZIEL, of Croydon, in the County of Surrey, Gentleman.
"IMPROVEMENTS IN WARMING APARTMENTS, AND IN STOVES, GRATES, RANGES, AND
OTHER FIRE-PLACES, AND THE FLUES CONNECTED THEREWITH."
This Invention relates to improvements in warming apartments, and in stoves,
grates, ranges, and other fire-places, and the flues connected therewith.
According to my Invention I separate the smoke carrying and ventilating
functions of the ordinary dwelling room chimney at the entrance thereto by forming
a chamber (herein-after called the interstitial chamber) close to the fuel, into and
through which I cause by draught the whole or a large portion of the gaseous
products from the burning fuel to pass accompanied by no more air than is
beneficial, and I provide at another place and at another level for the entrance into
the chimney of the ventilation draught.
I sometimes further protect the combustion draught against interference of the
ventilation draught, or circulation of air in the room, by a reverberatory plate or
cover over the fuel.
The air for combustion may be taken from below upwards, from above down-
wards, or from the front backwards through the fuel, or a combination of these
directions according to circumstances and the fuel employed. I improve the
manner of using fuel, especially cheap small coal for domestic and cooking fires, by
employing a step grate or "trippenrost" on which to rest the fuel.
I make the internal construction of the interstitial chamber (above referred to)
such as to expose.large surfaces of metal or other material with interstices between.
The hot gaseous products from the burning fuel in flowing through this interstitial
chamber raise the temperature of the several surfaces impinged upon, which in time
and in turn promote the more nearly complete combustion of such of the passing
matters as are still combustible.

page_text: The interstitial chamber has two or more exits (each regulated by a valve, if
desired), by one or more of which exits its whole gaseous contents may be dis-
charged directly from the chamber into the chimney. The chamber may be so
placed as to radiate heat for the benefit of one room or two.
Instead of the products of combustion being discharged from the interstitial
chamber directly into the chimney part, or the whole may be sent by the other
exits into channels or caliducts, traversing about or under and out in front of the
fire, and, if desired, beyond the line of the mantel shelf, which caliducts terminate
in, or communicate with an uptake flue which discharges into the chimney at some
distance above the level of the fire.
In one application of my Invention this uptake is made to pass close to the fuel
where it divides temporarily into a series of tubes, through, between which the
gaseous products from the fire pass into the interstitial chamber while the bodies
of the tubes serve as grating to prevent the fuel itself entering. This arrange-
inent promotes an instant draught in the uptake on lighting the fire.
In another application I wind the uptake or a branch of it more or less on
several sides of the fuel to ensure a vigorous draft.
The caliducts are made of metal or other fire resisting material, or combinations
of them, and may be more or less convoluted.' Those traversing horizontally may
lie upon the hearthstone, or be supported so as to leave an air space between, and
may be exposed to view or be encased and concealed, or they may be embedded in
dry or moist-sand-or-other-material, and the exposed surfaces dressed with
decorative tiles or other covering. A shallow spreading box, suitably divided
internally, may be used in lieu of the independent horizontally traversing caliducts
and be treated in like manner with decorative tiles or other coverings. By what-
ever means these horizontally traversing caliducts are constructed the passage
through them of hot gases from the interstitial chamber forms a hypocaustic hearth
which gives off heat by radiation, and, in addition, offers surfaces of considerable
area conveniently placed for communicating heat by contact.
The rapidity with which the hypocaustic hearth shall absorb and give up heat
can be adapted to each particular case by using slow or quick conductors or
radiators, and varying the thickness thereof in its internal and external construction
and decoration. Where it is practicable to have air supplied from without by a
special inlet it is desirable that part should directly supply the fire, and that the
other part should impinge upon the hypocaustic hearth before mingling with the
air of the room.
I regulate the hygrometric condition of the air of a dwelling room affecting alike
its capacity of absorbing radiant heat and its wholesomeness by the insensible
evaporation of water concealed and kept clean in closed vessels more or less porous,
and to which water salines or other substances are added to keep it sweet and
pleasant, and if exposed to much heat to prevent the agitation of boiling.
I further take advantage of the great specific heat of water, i.e., its capacity to
store up heat by placing upon the hearth, when convenience allows and when for
large rooms it may be desirable, hollow ornamental or sculptured figures containing
water with or without other substances added. These water tank figures receive
heat from the hearth or from the radiation of the fire, and are favourably placed
to genially warm the air of an apartment. Perforations may also be provided to
allow of the escape of vapour or steam.
I substitute for the sides ordinarily employed in the fire-place recess-improved
reflecting sides, formed of as thin a film of metallic reflecting surface as may be
convenient of gold, silver, steel, or other metals or alloys, backed by slow con-
ducting materials, such as wood, selenite, gypsum, &c., of substantial thickness;
or I apply a metallic film, as described, to existing fire or stove grate sides to
improve their reflective and restrain their absorptive action on radiant heat.
When I employ a surface other than metallic I select a substance little pervious
to heat rays of low refrangibility.
I conceal from view in an improved manner the cinder ash and dust which fall

page_text: from domestic fire-grates in general by forming a screen to hang like the fringe of
a curtain from the lower front part of the ordinary fire basket, so as at once to yield
on any ashes, &c., being pushed through below it and to resume its normal position
on that being done. This fringe may be formed of hollow or solid prisms, or rods,
or other pieces of metal, or other materials, or partly both, and may run on a rod
curtainwise,
SPECIFICATION filed in pursuance of the conditions of the Letters Patent, and
of an Order of the Lord Chancellor, by the said Thomas Brown Dalziel in
the Great Seal Patent Office on the 7th April 1877.
THOMAS BROWN DALZIEL, of Croydon, in the County of Surrey, Gentleman.
"IMPROVEMENTS IN WARMING APARTMENTS, AND IN STOVES, GRATES, RANGES, AND
OTHER FIRE-PLACES, AND THE FLUES CONNECTED THEREWITH."
According to my Invention I separate the smoke carrying and ventilating
functions of the ordinary dwelling room chimney at the entrance thereto by forming
close or near to the fuel of the fire-grate a chamber (herein-after called the inter-
stitial chamber), into and through which I cause by draught the whole or a large
portion of the gaseous products from the burning fuel to pass accompanied by no
more air than is beneficial & requisite for combustion of these products, and for
the entrance of the ventilation draught into the chimney I provide access at
another place and another level.
I further sometimes protect the combustion draught from interference of the
ventilation draught or circulation of air in the room by a reverberatory plate or
cover over the fuel.
The air for combustion, whether drawn from the apartment entirely or supple-
mented from exterior sources, may be taken from below upwards, from above
downwards, or from the front backwards through the fuel, or a combination of
these or any other directions according to circumstances and to the fuel employed.
I improve the manner of using fuel, especially cheap small coal for household and
cooking fires, by employing a step grate or trippenrost on which to rest the fuel.
I make the internal construction of the interstitial chamber, above referred to,
such as to expose large surfaces of metal or other material with interstices between.
The hot gaseous products from the burning fuel in flowing through this interstitial
chamber raise the temperature of the several surfaces impinged upon, which in time
and in turn promotes the more nearly complete combustion of such of the passing
matters as are still combustible. Thus the hydrogen, hydrocarbons, carbonic oxide;
& other combustible gases thrown off by the heated fuel passing into the inter-
stitial chamber mixed with air, are there usefully consumed instead of being inerely
volatilized as occurs in the ordinary fire-grate.
The interstitial chamber has two or more exits, each regulated by a valve if
desired, by one or more of which its whole gaseous contents may be discharged
directly from the chamber into the chimney.
Instead of this direct discharge into the chimney from the interstitial chamber
part or whole of its gaseous contents may be sent into channels or caliducts,
traversing about or under and out in front of the fire, and, if desired, beyond the
line of the mantel shelf, which caliducts terminate in or communicate with an
uptake flue which discharges into the chimney at some distance above the level
of the fire. This uptake flue creates the draught by which the hot gases are drawn
through either horizontal or descending channels or caliducts.
The caliducts are made of metal or other fire-resisting material or combinations.
of them, Those traversing horizontally may be independant channels, or tubes, or
a shallow spreading box suitably divided internally into such channels or caliducts,
and may rest upon the hearth stone or be supported upon it so as to leave an air
space between. The caliducts may be exposed to view. on the hearth or be

page_text: embedded in dry or moist sand or other material, and the exposed surfaces dressed
with decorative tiles or other covering, but preferably preserving an air space next
to the hearthstone. By whatever means these horizontally traversing caliducts
are constructed the passage through them of hot gases from the interstitial chamber
forms a hypocaustic hearth which gives off heat by radiation, and in addition
affords surfaces of considerable area conveniently placed for communicating heat by
contact.
I also arrange a hypocaustic hearth, which mainly derives its heat from the
bottom of the fuel bed resting on it, forming in fact a table with very short
supports standing on the hearthstone, on which the fuel bed of the grate is laid
flat. With both forms of hypocaustic hearth I prefer that they should be supported
from the hearthstone, leaving an air space between so that both the under and the
upper surfaces are effective. And when fresh air can be brought in from without
by special inlet in the neighbourhood of the fire-place, it is genially warmed by
impinging upon the hypocaustic hearth and its appurtenances before entering the
room.
In certain cases it is convenient to waylay part of this fresh air supply for
combustion of the fuel in lieu of drawing entirely upon the air of the room for that
purpose.
The rapidity with which the hypocaustic hearth shall absorb & give up heat can
é adapted to each particular case by using slow or quick conductors, and or
-radiators,-and-varying thicknesses-thereof-in-its-internal & external_construction
and decoration.
I regulate the hygrometric condition of the air of a dwelling room, affecting
alike its capacity of absorbing radiant heat and its wholesomeness, by the
insensible evaporation of water, concealed and kept clean in closed vessels more or
less porous & tubular for increase of acting surface, placed in the neighbourhood
of the fire or otherwise conveniently, and to which water salines or other substances
are added to keep it sweet and pleasant, and if exposed to much heat to prevent
the agitation of boiling.
I further take advantage of the great specific heat of water, that is, its capacity
to store up heat by placing upon the hearth when convenience allows, and when
for large rooms it may be desirable, hollow ornamental or sculptured figures con-
taining water with or without other substances added. These water-tank figures
receive heat from the hearth or from the radiation of the fire, and are favorably
placed to genially affect the atmosphere of or air flowing into apartments. Portions
of these figures may be perforated or porous, to allow of the escape of steam or
moistened air as well as tubular for increase of acting surfaces.
I substitute for the sides ordinarily employed in the fire-place recess improved
reflecting sides, formed of as thin a film of metallic reflecting surface as may be
convenient, of gold, silver, steel, or other metals or alloys, backed by slow con-
ducting materials, such as wood, selenite, gypsum, &c., or combinations of them of
substantial thickness, or I apply a metallic film, as described, to existing fire or
stove grate sides to improve their reflective and restrain their absorptive action on
radiant heat.
When I employ a surface, other than metallic, I select a substance little pervious
to heat rays of low refrangibility. I conceal from view in an improved manner the
cinder, ash, & dust, which fall from domestic fire-grates in general, by forming
a screen to hang like the fringe of a curtain from the lower front part of the
ordinary fire basket, so as at once to yield on any ashes &c. being pushed through
below it and to resume its normal position on that being done. This fringe may
be formed of hollow or solid prisms, or rods, or other pieces of metal, or other
materials, or partly both, and may run on a rod curtainwise.
And in order that my Invention may be fully understood, I annex Drawings of
several parts thereof which I now proceed to describe.
Drawing No. 1 is a plan, and Drawing No. 2 a relative section of an arrangement
of hypocaustic hearth and interstitial chamber as applied to the ordinary dwelling

page_text: room stove grate. The bottom and two sides of the fuel bed are solid fire lump, the
two angular or corner pieces are pierced perpendicularly and the back fire lump pierced
both perpendicularly & having smaller channels slanting downwards & forewards
from the perpendicular channels. The perforated lumps draw air from the channel
From the fuel when
a, c, on the top of which channel the solid side lumps rest.
kindled the smoke & gases enter the mouth of the interstitial chamber marked I, C,
as seen in Drawing No. 2, the top of which chamber is closed by an adjustable
flap. The descending caliducts marked d, c, begin at the top of the chamber I, C,
and descend until they communicate with the horizontal caliducts marked h, c.
The angular side of the descending caliducts, which is marked A, D, in Drawing
No. 1, is shorter by two to three inches than the other enclosing sides, and through
the opening thus formed the interstitial chamber I, C, discharges downwards into
the horizontal caliducts h, c, which traverse forwards and then backwards under
the fuel bed into the uptake marked u, p.
Drawing No. 4 is a plan of the horizontal caliducts; Drawing No. 5 is a section,
which, in conjunction with Drawing No. 4, shews the method I prefer for bringing
in fresh air, but if there is no such special inlet the hypocaustic hearth will still
warm the apartment. For the ventilation draught there is a hinged flap marked V, F,
which at no time completely closes the space over which it is placed. But the
well-known plan of making openings into the chimney at some little distance below
the ceiling is probably better than openings below the level of the mantel shelf, and
such high openings act well when the air admitted at the hearth is plentiful. The
openings in the horizontal caliducts marked x are apertures for cleaning these
ducts, and are closed with a movable cover. Attached to the front plate of the
chamber I, C, are flanges to increase the surface and one central division to fairly
divide the draft right & left. But I do not confine myself to the arrangement
with two descending ducts, as by enlarging their capacity one side may take the
entire down draught & the other serve instead of uptake by increasing its height
to the height of the present uptake. The needful corresponding changes in the
horizontal caliducts are obvious.
Instead of a solid fire-lump bottom to the fuel an ordinary grating, with ashes
drawer below, may be used if the fuel has much ash. It is obvious that the hori-
zontal caliducts may come very little forward if a hot fire is kept up, as the heat from
the bottom of the fuel bed will suffice to warm the incoming air, and this plan is
applicable to the common fire-grate without either caliducts or even the interstitial
chamber, but without the latter the combustion of the fuel is very much less complete.
Drawing No. 3 shews a step grate; it can be made of any slope required.
In witness whereof, I, the said Thomas Brown Dalziel, have hereunto set
my hand and seal, this Twenty-ninth day of March, One thousand eight
hundred and seventy-seven.
THO. B. DALZIEL. (L.S.)

page_text: form, size and position, as applied to different kinds
of fire grates and ranges. so long as regard, is had to
the essential of a narrowed mouth or entrance which
produces a sharp/concentrated draftmear to the fuel best,
thus promptly catching the more • volatile gaseous emari-
ations as they arise from the kindled fuil, and over which
volatile gases a sluggish current or ordinary diffused
draught has no effective control. The mouth of
the 1. C. Chamber effectively placed, its body, which radiates
heal in any unobstructed direction, may then be variously
shaped and placed to suit each case.