A NEW CONSTRUCTION FOR A HEARTH, APPLICABLE TO ALL FIRING CONSTRUCTIONS OR FIRE-PLACES
Year: 1855

page_text: LETTERS PATENT to William Eisenmann, Merchant, at Berlin, for the
Invention of "A NEW CONSTRUCTION FOR A HEARTH, APPLICABLE TO ALL
FIRING CONSTRUCTIONS OR FIRE-PLACES."
Sealed the 17th July 1855, and dated the 20th January 1855.
PROVISIONAL SPECIFICATION left by the said William Eisenmann at
the Office of the Commissioners of Patents, with his Petition, on the
20th January 1855.
I, WILLIAM EISENMANN, Merchant, at Berlin, do hereby declare the nature
of the said Invention for "A NEW CONSTRUCTION FOR A HEARTH, APPLICABLE TO
ALL FIRING CONSTRUCTIONS OR FIRE-PLACES," to be as follows:-
This Invention is designed to effect a more perfect and complete combustion
than heretofore of the inflammable gases evolved from the fuel; it creates a
greater amount of heat from the same fuel than has hitherto been obtained by
hearths of the most approved construction, and produces little or no smoke.
This improvement is effected by contracting the hearth above the fire bars,
and by introducing at such contracted part small jets of atmospheric air or
steam to assist the combustion. These contractions may be formed in a
variety of ways, some of which are subjoined, the principle still remaining the
same. In the first place, I propose to form the contractions by causing-the-

page_text: walls of the hearth to jut out or project over the fire bars in a sloping direction.
These sloping surfaces soon assuine a white heat, and they, together with
the atmospheric air or steam admitted at the contracted part of the hearth,
will cause the complete combustion of the unconsumed inflammable gases, that
would otherwise escape in the form of smoke.".
In wide hearths, where two much projecting of the walls would be incon-
venient, a partition.wall.should-be-formed-in-the-centre-of-the-hearth, with
projecting sides inclining towards the sides of the hearth, and furnished with a
channel, through which the air or steami is introduced. In applying this
Invention to furnaces of cylindrical steam boilers where the fire bars are
placed in the metal flue inside the body of the furnace, I employ perforated
hollow bodies of a tubular or other form, placed in a sloping or slightly inclined
direction, either over or behind the fire bars, in such a manner that the flame.
and gases are compelled to pass through the space between the same and
through the perforations therein. I admit atmospheric air or steam, so as to
consume the whole of the combustible gases evolved from the fuel, as before
stated.
SPECIFICATION in pursuance of the conditions of the Letters: Patent, filed
by the said William Eisenmann in the Great Seal Patent Office on
the 20th July 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
EISENMANN, Merchant, at Berlin, send greeting
..
...WHEREAS Her most Excellent Majesty Queen Victoria,, by Her Letters
Patent, bearing date the Twentieth day of January, in the year of our Lord,
One thousand eight hundred and. fifty-five, in the eighteenth year of Her reign,
did; for Herself, Her heirs and successors, give and grant unto me, the said
William Eisenmann, Her special licence that I, the said William Eisenmann,
my.executors, administrators, and assigns, or such others as I, the said William
Eisenmann, my executors, administrators, and 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 lawfully 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 "A NEW CONSTRUCTION FOR A.
HEARTH, APPLICABLE TO ALL FIRING CONSTRUCTIONS OR FIRE-PLACES," upon the con-
dition (amongst others) that I, the said. William Eisenmann, by an instrument.
in writing under my hand and seal, should particularly describe and ascertain
1
L'
7 ...

page_text: 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. William Eisenmann, do hereby declare
the nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof (that is to say):-
...This Invention of a new construction for a hearth applicable to all firing
constructions or fire-places is designed to effect a more perfect- and complete
combustion than heretofore of the inflammable gases evolved: from fuel of
various kinds.
It produces a greater amount of heat than has hitherto been obtained by
hearths of the most improved construction, and produces little or no smoke.
The economy of the fuel varies from ten, to thirty per cent., according to the
quality of the fuel, the economy being greater in fuel of low combustible
power..
'
The construction of the said Invention will be readily understood from the
following description thereof, reference being had to the annexed Drawing, and
to the figures and letters marked thereon, similar. letters of reference being
placed upon corresponding parts in the various Figures:......
.
Figure 1 is a vertical transverse section of the hearth, as applied to a cylin-
drical steam boiler with a single flue; Figure 2 is a vertical longitudinal
section; and Figure 3, an horizontal section of the same. Figures 4, 5, and 6
are similar views of the Invention, as applied to a cylindrical. steam boiler with
two flues. a, a, are the fire bars, and-b, b, is the hearth or fire-place. The
upper part of the hearth 6 is constructed with one or more contractions c, c,
which contractions extend either over part or the whole length of the grate ȧ.
At the point of contraction 'c'the hearth is-pierced on each side with small
holes é, for the admission of atmospheric air or steam, and communicating with
the longitudinal channels d formed in the brickwork. These channels'd com-
'municate with the external atmosphere or with a steam boiler, and are provided
with dampers; as at f, for the purpose of regulating the amount of atmospheric
air or steam admitted. These contractions serve for a double purpose; . firstly,
the interior walls 9, 9; of the furnace projecting over the fire bars, and con-
stantly exposed to the flame, present to the unconsumed gas 'surfaces. at a
white heat; and, secondly, the said contractions serve to combine the air which
enters through the grate a more thoroughly with the flame, by. which means
'the oxygen contained therein is almost entirely. disengaged. The air which

page_text: :
enters through the openings e still further assists the combustion of the uncon-
sumed gases. The said air in passing through the brickwork becomes suffi-
ciently heated, and the unconsumed gases are at so high a temperature that
combustion immediately ensues, and very little (if any) combustible gas or smoke
escapes. The form of construction of this hearth may be varied, according to
the nature and dimensions of the surface or space to be heated, and also to suit
the nature of the combustibles.employed, and other circumstances, the same
principle being still adhered to; for instance, the contractions c may be made
narrower or wider, narrower at the back than at, the front, and vice versa.
The distance between the contractions and the fire bars may be increased or
diminished. The number and position of the openings e may also be varied.
They may be placed upon either or both sides of the contractions c, and may
extend the whole length of the furnace, as exhibited at Figure 3, or only a
part of the same, as shown at Figure 6. In grates wherein a great. breadth
of heating surface. is required, it is preferable to construct the hearth with a
central partition, as exhibited at Figures 4, 5, and. 6, because too great a pro-
jection of the interior walls would be found difficult of construction, and also
because the central part of the flame could not in that case be furnished with
a sufficient quantity of atmospheric air. This central partition & divides the
fire-place into two distinct hearths b, b, and is provided with small openings
i, i, communicating with a channel k to supply air to the flame.. This partition
may be constructed either higher or lower than exhibited in the Drawing,
and of various forms, according to circumstances, but always so that the flamo
from both sides can meet over the top of the same.
Lastly, in cases, where it is not practicable or desirable to use much brick-
work, as in boilers. wherein the fire-place is situated within the body of the
boiler, the contractions are to be formed by placing therein strong hollow
bodies or cylinders of fire brick or other suitable material, supported at each
end, as,exhibited at Figures 7, 8, 9, 10, 11, and 12; Figure 7 being a trans-
verse section, Figure 8 a vertical longitudinal section, and Figure 9 an
horizontal longitudinal section, of a suitable arrangement for this purpose.
1,1, are the tubes, supported at m, and n in an inclined position, two or more
tubes or hollow bodies being so placed as to leave narrow spaces o, o, serving
the. purpose of the contractions c, in Figures 1 to 6. These hollow bodies or
pipes are provided with interior channels p, and with small perforations q, for
the admission of air or steam. In boilers with internal furnaces, where cir-
cumstances will not. admit of placing these hollow bodies or tubes over the
grate, solid partitions of cylindrical or other form may be.employed, and may
be arranged as exhibited at Figures 10, 11, and 12, in which r,r, is an, arch

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of brickwork, formed over part or the whole length of the grate and over the
fire bridge. The divisions or partitions are placed behind the bridge, and
supported at one end by the arch and at the other by the brickworks, the
flame passing through the spaces o between the said partitions. The atmo-
spheric air or steam in this instance is admitted by means of the iron pipes d, d,
passing under the grate a, a, to the fire bridge, and communicating with the
vertical channels e, e, in the fire bridge.
Having thus described the nature and object of my said new construction
for a hearth, applicable to all firing constructions or fire-places, together
with the best means I am acquainted with for carrying the same into practical
effect, I would remark, in conclusion, that I do not intend to limit myself to the
precise form or construction of furnace exhibited in the Drawing, but reserve
to myself the right to modify the same, according to circumstances, provided
that the peculiar character of my Invention be retained.
In witness whereof, I, the said William Eisenmann, have hereunto set
my hand and seal, this Eighteenth day of July, in the year of our
Lord One thousand eight hundred and fifty-five.
Witness,
WILLIAM EISENMANN, (L.s.)
Berlin, Auguststrasse, 68.
(L.S.) JULES HENRY FERDINAND PRILLWITZ,
Berlin, 40, Rosenthal Street.