IMPROVE- MENTS IN FURNACES AND FIRE-PLACES FOR THE BETTER COMBUSTION OF FUEL
Year: 1860

page_text: LETTERS PATENT to John Henry-Johnson, of 47, Lincoln's Inn Fields,
in the County of Middlesex, and of 166, Buchanan Street, in the City
of Glasgow, North Britain, Gentleman, for the Invention of "IMPROVE-
MENTS IN FURNACES AND FIRE-PLACES FOR THE BETTER COMBUSTION OF FUEL."-
A communication from abroad by Nicholas Francois Corbin Desboissieres,
of Paris, in the Empire of France. . .
Scaled the 8th June 1860, and dated the 3rd January 1860.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at
the Office of the Commissioners of Patents, with his Petition, on the
3rd January 1860.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, and of 166, Buchanan Street, in the City of Glasgow, North
Britain, Gentleman, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN FURNACES AND FIRE-PLACES FOR THE BETTER COMBUSTION OF
FUEL," a communication from abroad by Francois Corbin Desboissieres, of
Paris, in the Empire of France, to be as follows:-
This Invention relates to a peculiar construction and arrangement of
furnaces and fire-places, whereby a more perfect and economic combustion is
accomplished. and the emission of smoke prevented.

page_text: These improvements are equally applicable to all furnaces and fire-places
fitted with fire-bars or grates, whether used in the forging of metals, in the
generation of steam, in stationary, locomotive, or marine boilers, and to the
ordinary domestic open fire-grate.
The chief object to be attained by this Invention is the obtainment of a
perfect mixed combustion, for which purpose it is proposed in furnaces other
than the domestic grate to divide the grate area into three portions by con-
structing along the centre thereof, so as to subdivide the grate into two smaller
grates of equal area, a dead surface of fire-brick supported upon iron plates,
and having a superficial area about equal to one of the two grates. The front
of the furnace so constructed is provided with a wide feed aperture of iron
extending in front of the two grates and dead surface. This aperture is
divided into three lengths by means of vertical hollow columns of cast iron,
through which air is allowed to circulate freely, and these apertures are closed
either by loose fire-bricks and small coal, or by sliding iron doors. In front of
the central opening a horizontal roller or rollers is placed upon which the
shovel of the stoker is supported when being introduced into the furnace with
fuel, and the vertical columns above referred to serve as lateral rests or bearing
supports for the poker or other tool used in stirring the fuel and pushing it on
to the grates from off the central dead surface, upon which all the green coal
is first deposited in supplying the furnace. By this means the green or fresh
coal is allowed to distil effectually upon the heated fire-brick dead surface
before it is pushed on to the grates on either side of it. An air aperture may
be formed in some cases leading to the dead surface, whereby more or less air
may be admitted to the fuel under the process of distillation, as required,
whilst at the same time facility is afforded for the introduction of a poker to
loosen and stir up the caking fuel on the dead surface.
In the case of the fire-boxes of locomotive engines, they will require to be
considerably extended forward at the lower portion, in order to obtain the
required grate area, which would otherwise be reduced by the introduction of
the central dead surface.
In applying these improvements to the existing open fire-grates for domestic
purposes, the whole of the fire-holding portion of the grate is surrounded by
fire-brick, and a considerable portion of the back of the grate is occupied by a
fire-brick dead surface, of about half the entire depth of the grate from back to
front, and extending laterally to within a short distance of the sides of the
grate, so that this dead surface will be enclosed on the front and two sides by
the horizontal bars of the fire-grate, and bounded on the back by the fire-brick

page_text: back of the grate. This back is made to project considerably forward, so as
to overhang the dead surface, and form a species of combustion chamber at
the back of the grate, the mouth of such chamber leading by a curved sweep
into the flue or up-take, which is built some distance in advance of the back of
the grate.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Henry Johnson in the Great Seal Patent Office on
the 3rd July 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47. Lincoln's Inn Fields. in the County of Middlesex.
and of 166. Buchanan Street, in the City of Glasgow, North Britain,
Gentleman, send greeting.
WHEREAS Iler. most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Third day of January. in the year of our Lord
One thousand eight hundred and sixty. in the twenty-third year of Her
reign, did, for Herself. Her heirs and successors,, give and grant unto
me, the said John Henry Johnson, Her special license that I. the said
John Henry Johnson, my executors, administrators, and assigns. or such
others as I, the said John Henry Johnson, my executors, administrators.
or assigns, should at any time agree with, and no others, from time to time
and at all times thereafter during the term therein expressed, should and law-
fully might make, use, exercise. and vend. within the United Kingdom of
Great Britain and Ireland, the Channel Islands, and Isle of Man, an
Invention for IMPROVEMENTS IN FURNACES AND FIRE-PLACES FOR THE BETTER
COMBUSTION OF FUEL," a communication from abroad by Nicholas Francois
Corbin Desboissieres, of Paris, in the Empire of France, upon the condition
(amongst others) that I. the said John Henry Johnson, by an instrument
in writing under my hand and seal, should particularly describe and ascer-
tain the nature of the said Invention. and in what manner the same was
to be performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date of the
said Letters Patent.
"
NOW KNOW YE, that I, the said John Henry Johnson, do hereby
declare the nature of the said Invention, and in what manner the same is

page_text: to be performed, to be particularly described and ascertained in and by the
following statement, reference being had to the accompanying Drawings, and
to the letters and figures marked thereon, that is to say:-
The said Invention relates to a peculiar construction and arrangement of
furnaces and fire-places. whereby a more perfect and economic combustion is
accomplished and the emission of smoke prevented. These improvements are
equally applicable to all furnaces and fire-places fitted with fire-bars or grates,
whether used in the forging of metals, in the generation of steam in stationary,
locomotive, or marine boilers, and to ordinary domestic open fire-grates. The
chief result to be obtained by this Invention is a perfect mixed combustion, for
which purpose it is proposed in furnaces, other than domestic grates, to divide
the surface supporting the fuel into three portions, by constructing along the
centre thereof so as to subdivide the said. surface into two smaller grates of
equal area, a dead surface of fire-brick supported upon iron plates, and having
a superficial area about equal to one of the two grates; the front of the furnace.
so constructed is provided with a wide feed aperture composed of iron extend-
ing in front of the two grates and dead surface. This aperture is divided into
three lengths by means of vertical hollow columns of cast iron, by which air is.
allowed to enter freely, and these apertures are closed either by loose fire-
bricks and small coal or by sliding iron doors. In front of the central opening
a horizontal roller or rollers are placed. upon which the shovel of the stoker
is supported when being introduced into the furnace with fuel, and the
vertical columns above referred to serve as lateral rests or bearing supports for
the poker or other tool used in stirring the fuel and pushing it on to the grates
from off the central dead surface upon which all the green coal is first
deposited when feeding the furnace. By these means the fresh coal is allowed
to disti effectually upon the heated fire-brick dead surface before it is pushed
on to the grates on either side of it. An air aperture may be formed in some
cases leading to the dead surface, whereby more or less air may be admitted
to the fuel under the process of distillation as required, whilst at the same
time facility is afforded for the introduction of a poker to loosen and stir up
the caking fuel on the dead surface. In the case of the fire-boxes of loco-
motive engines they will require to be considerably extended forward towards
the tender at the lower portion in order to obtain the required grate area.
which would otherwise be reduced by the introduction of the central dead
surface. In applying these improvements to the existing open fire-grates for
domestic purposes, the whole of the fire-holding portion of the grate is sur-
rounded by fire-brick, and a considerable portion of the back of the grate is

page_text: occupied by a fire-brick dead surface of about half the entire depth of the
grate from back to front, and extending laterally to within a short distance of
the sides of the grate, so that this dead surface will be enclosed on the front
and two sides by the horizontal bars of the fire-grate, and bounded on the back
by the fire-brick back of the grate. This back is made to project considerably
forward. so as to overhang the dead surface and form a species of combustion
chamber at the back of the grate, the mouth of such chamber leading by a
covered passage into the flue or uptake.
And in order that the said Invention may be fully understood, I shall now
proceed more particularly to describe the same, and for that purpose I shall
refer to the several Figures on the sheet of Drawings hereunto annexed,
the same letters of reference indicating corresponding parts throughout all
the corresponding Figures.
Figures 1, 2, 3, 4, and 5, on Sheet 1 of the Drawings, represent various
views of a welding furnace constructed according to this Invention. Figure 1
is a section taken along the line 3-4, in Figure 2: this view represents the
grate divided into two equal parts C and D. and also the dead surface in fire-
brick E. upon which the distillation of the fresh fuel takes place, and the
combustion of its gas is effected. The apparatus so constructed is enclosed
in the ordinary manner by the side walls, the bridge. the roof, and the furnace
front, which latter consists of a species of box or frame of cast iron, the base
of which forms a kind of dead plate F. which carries a wrought-iron roller G,
over and upon which the stoker, when feeding in the fuel, slides his shovel,
which is formed with raised sides: this dead plate is also provided with two
cast-iron columns II, I, which support the inclined head or cap K. The dead
surface E of the furnace and the two compartments of the grate are thus
equally accessible whether for removing the coal from such dead surface on to
the grates, or from the grates on to the dead surface in order to clean the
bars and remove clinkers, which operation may be accomplished in a few
minutes, the clinkers and scoriae being pushed down into the ash-pit by first
removing two or three of the grate bars, and then replacing them to be again
covered with the incandescent fuel on the dead surface. Figure 2 is a
vertical section taken along the line 4-5. in Figure 3, shewing the dead sur-
face E; Figure 3 is a vertical section taken along the line 1-2, in Figure 1,
and shows the two compartments of the grate and the mode of fixing the six
cast-iron bears which support the bars; Figure 4 is a section taken along the
line 6-7, in Figure 1, and shews the three cast-iron bearers which support
the bars of each grate; and Figure 5 is a front elevation of the furnace

page_text: corresponding to the previous Figures. with the exception of the opening s.
which leads to the dead surface E, and facilitates the raising or stirring of
the fuel thereon.
Figures 6 and 7 on Sheet 2 of the Drawings represent a stationary steam
boiler furnace constructed according to this Invention; Figure 6 shews the
two compartments A and B of the grate and the fire-brick dead surface c.
which is of the same area as each of the compartments of the grate; D is the
fire bridge. E the passage for the flame, and T. K. the water tubes of the
boiler. Figures 8, 9, 10, and 11 represent various views of a domestic fire-
place constructed according to this Invention: Figure 8. which is a section
taken along the line 1-2. in Figure 9. shews the cast-iron grate A and the
two wings B, B. which surround. the dead surface composed of fire-brick D,
and also shews the boundary walls E. E. of fire-brick covered in by the brick
roof or crown I, as shewn in Figures 9 and 10. Figure 11 shews a front
view of the fire-place constructed on the above principles. The fuel being
supplied. to the dead surface D, becomes transformed into a light and porous
coke. giving off hardly any. if any, smoke, and will then burn in a perfect
manner on the grate. effecting a saving of nearly forty per cent.
Figures 12, 13, 14, and 15, on Sheet 3 of the Drawings represent various
views of a locomotive fire-box constructed according to this Invention, whereby
coal may be burnt without smoke. Figure 12, which is a section taken along
the line 1-2, in Figure 13, shews the two compartments A and B of the grate
separated by the fire-brick dead surface C. shewn also in Figure 13, which is
a vertical longitudinal section taken along the line 3-4, in Figure 12. The
lower part of the fire-box is extended forward beneath the ordinary foot plate
towards the tender. the bottom of which is considerably lowered, as shewn in
the Drawing, for the accommodation of the stoker, the fire-door being in the
lower or extended portion of the fire-box. Figure 14 represents a transverse
section of the extended portion of the fire-box taken along the line 5-6, in
Figure 13, and shews the two divisions of the grate with the dead surface
between them; Figure 15 is an end elevation of the fire-box end of the
engine, shewing the mode of constructing the front parts with the sliding fire
doors. The divided fire-grate, with the fire-brick dead surface, may thus
obviously be employed in all cases where an ordinary or other grate has been
hitherto used.
7
Having now described and particularly ascertained the nature of the said
Invention, and the manner in which the same is or may be used or carried
into effect. I would observe, in conclusion, that what I consider to be novel

page_text: and original, and therefore claim as the Invention secured to me by the
herein-before in part recited Letters Patent, is,-
First, the general construction and arrangement of furnaces or fire-places
for the better and more economic combustion of fuel, as herein-before
described.
Second, the application and use of fire-places so constructed that the middle
portion of their bottoms or parts supporting the fuel consist of a fire-brick
dead surface and a grate on each side, as herein-before described.
In witness whereof, I, the said John Henry Johnson, have hereunto
set my hand and seal, this Third day of July, One thousand eight
hundred and sixty.
J. HENRY JOHNSON. (L.s.)