IMPROVEMENT
Year: 1880

page_text: PROVISIONAL SPECIFICATION left by the said John Jobson at the Office of
the Commissioners of Patents on the 11th November 1880.
JOHN JOBSON, of Derby, in the County of Derby, Ironfounder.
IN OPEN FIRE-PLACES."
"
IMPROVEMENTS
The object of the Invention is to effect the consumption of the smoke produced
by the combustion of coal in open fire places, and the Invention applies particularly
to that class of open fire places in which the back, the sides, and the bottom of the
receptacle for the fuel or the combustion chamber are formed of solid fire brick or
other suitable material, but it is not confined thereto.
To carry my improvements into effect I form an opening through the bottom of
the brick or other suitable material at the back of the combustion chamber, or I
form such openings through the bottom of the sides. Such opening or openings I
prefer to incline slightly upwards into a passage or pocket behind the ordinary
back of the open fire place, or into passages or pockets at the sides thereof. I also
apply a secondary back or screen in front of the ordinary back and forming a
chamber opening upwards just near the upper part of the ordinary back, and this
chamber opens downwards into the passages or pockets above referred to as being
behind the back and at the sides of the open fire-place. These back and side
passages or pockets and the ordinary front portion of the open fire place over the
combustion chamber have flaps, by which communication may be opened or closed
to the ordinary flue. Advantage is obtained by a passage or passages for air from
the underside of the combustion chamber to the back passage or pocket, as thereby
the combustion of the smoke is facilitated therein.
In use when the flap or flaps to the upper part of the back or side passages or
pockets are open, and that to the main front chamber is closed, smoke generated in
the fire place will be drawn down through the fire, out through the opening or
openings in the back or sides of the bottom of the fire chamber, and will become

page_text: consumed, and the heated products will rise up the back or side passages or pockets,
whilst smoke from the top of the fire rising up in the front main chamber will be
drawn down the front extra chamber to meet the heated products rising in the
back or side passage, chamber, or pocket, and will thereby become consumed.
By closing the back and side flaps and opening the front one, the grate will then
be in a condition to operate as an ordinary "Abbotsford," or other open fire place.
SPECIFICATION in pursuance of the Conditions of the Letters Patent filed by
the said John Jobson in the Great Seal Patent Offico on the 11th May 1881.
IMPROVEMENTS
JOHN JOBSON, of Derby, in the County of Derby, Ironfounder.
IN OPEN FIRE-PLACES."
st
The object of the Invention is to effect the consumption of the smoke produced
by the combustion of coal in open fire-places, and the Invention applies particularly
to that class of open fire places in which the back, the sides, and the bottom of the
receptacle for the fuel or the combustion chamber are formed of solid fire-brick or
other suitable material, but it is not confined thereto.
To carry my improvements into effect I forin an opening through the bottom of
the brick or other suitable material at the back of the combustion chamber, or I
form such openings through the bottom of the sides to open upwards into a passage
or pocket behind the ordinary back of the open fire place, or into passages or
pockets at the sides thereof. I also apply a secondary back or screen in front of
the ordinary back, and forming a chamber opening upwards, just near the upper
part of the ordinary back, and this chamber opens downwards into passages or
pockets above referred to as being behind the back and at the sides of the open
fire place. These back and side passages or pockets and the ordinary front portion
of the open fire place over the combustion chamber have flaps by which
communication may be opened or closed to the ordinary flue. Advantage is
obtained by a passage or passages for air from the underside of the combustion
chamber to the back passage or pocket, as thereby the combustion of the smoke is
facilitated therein.
In use when the flap or flaps to the upper part of the back or side passages or
pockets are open, and that to the main front chamber is closed, smoke generated in
the fire place will be drawn down through the fire, out through the opening or
openings in the back or sides of the bottom of the firo chamber, and will become
consumed, and the heated prodnets will rise up the back or side passages or pockets,
whilst smoke from the top of the fire rising up in the front main chamber will bo
drawn down the front extra chamber to meet the heated products rising in the
back or side passage chamber or pocket and will thereby become consumed.
By closing the back and sido flaps and opening the front one the grate will then

page_text: to operate as an ordinary
ALOQOLSIOra or owner open ure
place.
But that the Invention may be the better understood I will by the aid of the
accompanying Drawings proceed more fully to describe the same.
DESCRIPTION OF THE DRAWINGS.
Figure 1 shews by front view, Figure 2 by vertical section, and Figure 3
by sectional plan view, an arrangement of open fire place according to my
Invention.
In each of these Figures the same letters indicate corresponding parts wherever
they occur. a is the framing of the fire place; b, the receptacle for the fuel or the
combustion chainber; b indicates the back, 6 the sides, aud 63 the bottom thereof;
c are the fire bars; d is the lid or moveable cover to be used when, according to my
present improvements, it is intended to prevent the direct passage of the smoke
and products of combustion from the fuel or combustion chamber up to the
chimney g; e is the opening through the back of the bottom of the coinbustion
chamber b, by which, when the direct passage upwards is closed by the closing of
the flap d, products of combustion pass from the ignited fuel in the chamber b to
the passage or pocket f, open at the top to the chimney g, and thence up in the
direction of the full arrows to the chimney g; h represents the back of the ordinary
fire place, but which I prefer to produce of a corrugated form, as shewn by Figure 3,
as thereby I am enabled to obtain increased heating surface therefrom; i represents
the secondary back or screen in front of the back h, forming a chamber j, by which,
when the upper part of the fire place is closed by the closing of the flap d, or
otherwise smoke and products of combustion rising up from the ignited fuel in tho
combustion chamber 6 will pass over the top of the plate i and down the passage j,
as indicated by the full arrows, and joining the products of combustion from the
bottom of the combustion chamber pass up the passage or pocket f.
When the flap d is open the passage of the smoke and products of combustion
will be in the direction indicated by the dotted arrows.
Figures 4, 5, and 6 show corresponding views to those just referred to, with a
slight modification by the application of bars to the bottom of the fuel
chamber b. In other respects the same letters are used to indicate corresponding
parts to those already referred to, and the full and dotted arrows represent the
different direction of the passage and products of combustion when the upper part
of the fire place is closed or open by the use of a flap or flaps d or otherwise.
Although I have shown the form of the bars r as dipping slightly downwards, they
may be of other form if desired.
Figure 7 shows a front view, Figure 8 an external edge view, and Figure 9 a
horizontal section of a modification of the arrangements described; Figure 10
shows a vertical section of the same taken through the lines 1, 1, of Figure 9.
Figure 11 shows a vertical transverse section taken through the lines 2, 2,
Figure 9. Similar letters are also used in this case to indicate corresponding parts
represented in the previous Figures. In this case there are side passages or
pockets l, l, so that when the flap d or the passage direct to the flue is otherwise
closed, the smoke and products of combustion rising from the ignited fuel in tho
fire chamber will pass, as indicated by the full arrows, by the openings 1, ', down
the passages or pockets l, l, and out therefrom by the passages 1, 3, under the fire
chamber b, and thence up through the bars m and through the ignited fuel at the
back to join the products of combustion passing from the back of the bottom of
the fuel in the fire chamber to the passage or pocket f, as indicated by full
arrows.
When the flap d, or other closing means to the upper part of the fire place is
open, the smoke and products of combustion will pass in the direction indicated by
the dotted arrows.
Figure 12 represents a front view; Figure 13, an edge view; Figure 14, a
sectional plan view; Figure 15, a vertical section through the lines 1, 1, of

page_text: Figure 14; and Figure 16, a vertical section through the lines 2, 2; Figure 14, of
a slight modification or combination of the arrangements previously described;
Figure 17 represents a front view of the bars c and front plate c separately.
In Figure 12 the front plate c¹, below the bottom of fire chamber, is shewn
removed.
Corresponding letters are applied in these Figures to parts corresponding in the
previous Figures.
It will be readily seen that the principal difference in this case is that the
openings into the passages or pockets are from the chamber j, so that smoke and
products of combustion rising up in the front of the plate i (when the upper part
of the fire chamber is closed by the cover d or otherwise), and passing down the
chamber j in place of thence at once passing from the bottom of that chamber j
into the pocket f, they pass by the openings, into the passages 1, 1, and from
those passages 1, 1, by the openings ³, 13, under the fire chamber b into the pocket f.
Air from the apartment in which such fire place is fitted also passes by openings o, o, o,
through hollow bars p, p, to tho pocket f
In these, as in the previous Figures, the full arrows indicate the direction of the
products of combustion when the passage direct to the chimney is closed by the
closing of the flap d, or by other suitable means, whilst the dotted arrows indicate
the passage of those products when the flap d is raised or the passage to the
chimney is otherwise freely open.
Having thus described my Invention, and means which I adopt in carrying the
same into effect, I would have it understood that I do not confine myself to the
precise details or arrangements of parts shown and described, as the same may be
varied without departing from the peculiar character of my Invention, but what I
claim is, the arranging or combining parts of open fire places of the character
described, whereby the smoke and products of combustion from the ignited fuel in
the fire chamber in their passago to the chimney are controlled in manner
substantially as described.
In witness whereof, I, the said John Jobson, have hereunto set my hand
and seal, this Tenth day of May, One thousand eight hundred and eighty
one.
JOHN JOBSON. (L.S.)