IMPROVEMENTS IN FURNACES
Year: 1858

page_text: LETTERS PATENT to Jean Baptiste Pierre Alfred Thierry, junior, of
Paris, in the Empire of France, for the Invention of "IMPROVEMENTS IN
FURNACES."
PROVISIONAL SPECIFICATION left by the said Jean Baptiste Pierre
Alfred Thierry at the Office of the Commissioners of Patents, with his
Petition, on the 22nd July 1858.
I, JEAN BAPTISTE PIERRE ALFRED THIERRY, junior, of Paris, in the
Empire of France, do hereby declare the nature of the Invention for
"IMPROVEMENTS IN FURNACES," to be as follows:-
This Invention has for its object improvements in furnaces. In the Speci-
fication of a former Patent granted to myself and others there was described
the introduction of jets of superheated steam above the fuel on the fire-bars
of a furnace. . Now, one part of my Invention consists in mixing atmospheric
air with the superheated steam before it passes into the furnace. For this
purpose each jet of superheated steam is admitted into a tube, one end of
which is open to the air, and in the other end there are a number of small
holes through which the superheated steam, together with atmospheric air,
passes into the furnace.
Another part of my Invention consists in superheating the steam before

page_text: introducing it into the furnace by passing it through hollow fire-bars. For
this purpose each fire-bar is made hollow, and steam is admitted from the
boiler into one end of the hollow chamber through a tube attached to the
end of the fire-bar, and to the other end of the fire-bar there is connected
another tube of smaller diameter than the first tube) which conveys the
steam into the furnace above the fuel, or both pipes may be connected to the
same end of the fire-bar, the pipe which conveys steam to the hollow chamber
of the fire-bar being in connection with a passage made in the fire-bar, which
passage conveys the steam into the other end of the chamber to that from
which the steam passes away into the furnace. Or in place of superheating
the steam by passing it through hollow fire-bars, the steam may be super-
heated by passing through chambers placed at the side of the furnace, the
two chambers being connected by a pipe at the back of the furnace, and the
steam from the boiler being admitted into the front of one of the chambers,
and passing into the furnace from the front of the other chamber, so that the
steam passes through both chambers before it passes into the furnace, and
the superheated steam, in place of being admitted into the furnace in jets, as
described in the Patent above referred to, may be passed into the furnace
through small holes formed in a rose or spreader.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Jean Baptiste Pierre Alfred Thierry in the Great Seal
Patent Office on the 22nd January 1859. .
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JEAN
BAPTISTE PIERRE ALFRED THIERRY, junior, of Paris, in the Empire of France,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-second day of July, in the year of our Lord
One thousand eight hundred and fifty-eight, in the twenty-second year of Her
-reign,-did,-for-Herself, Her heirs and successors, give and grant unto me, the
said Jean Baptiste Pierre Alfred Thierry, Her special licence that-I,-the-said-
Jean Baptiste Pierre Alfred Thierry, my executors, administrators, and
assigns, or such others as I, the said Jean Baptiste Pierre Alfred Thierry,
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,

page_text: within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN FURNACES," upon
the condition (amongst others) that I, the said Jean Baptiste Pierre Alfred
Thierry, my executors or administrators; by an instrument in writing under
my, or their, or one of their hands and seals, should particularly describe
and ascertain 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 Jean Baptiste Pierre Alfred Thierry, do
hereby declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say :-
This Invention has for its object improvements in furnaces. In the Speci-
fication of a former Patent granted to myself and others there was described
the introduction of jets of superheated steam above the fuel on the fire-bars
of a furnace. Now, one part of my Invention consists in mixing atmospheric
air with the superheated steam before it passes into the furnace. For this
purpose each jet of superheated steam is admitted into a tube, one end of
which is open to the air, and in the other end there are a number of small
holes through which the superheated steam, together with atmospheric air,
passes into the furnace.
Another part of my Invention consists in superheating the steam before
introducing it into the furnace by passing it through hollow fire-bars. For
this purpose each fire-bar is made hollow, and steam is admitted from the
boiler into one end of the hollow chamber through a tube attached to the end
of the fire-bar, and to the other end of the fire-bar there is connected another
tube (of smaller diameter than the first tube) which conveys the steam into
the furnace above the fuel, or both pipes may be connected to the same end
of the fire-bar, the pipe which conveys steam to the hollow chamber of the
fire-bar being in connection with a passage made in the fire-bar, which
passage conveys the steam into the other end of the chamber to that from
which the steam passes away into the furnace. Or in place of superheating
the steam by passing it through hollow fire-bars, the steam may be super-
heated by passing through chambers placed at the side of the furnace, the
two chambers being connected by a pipe at the back of the furnace, and the
steam from the boiler being admitted into the front of one of the chambers,
and passing into the furnace from the front of the other chamber, so that the

page_text: steam passes through both chambers before it passes into the furnace, and
the superheated steam, in place of being admitted into the furnace in jets, as
described in the Patent above referred to, may be passed into the furnace
through small holes in a rose or spreader.
And in order that my said Invention may be most fully understood and
readily carried into effect, I will proceed to describe the Drawings hereunto.
Figures 1, 2, and 3 show sections of different forms of apparatus for mixing
superheated steam with atmospheric air before admitting it into a furnace.
a is a pipe, the end of which projects into a larger tube b, and superheated
steam is introduced into the tube 6 through the pipe a in the end of the
tube b, through which the pipe a passes, there are holes through which
air may pass into the tube, the other end of the tube 6 projects into a furnace
above the fire-bars, and is placed, by preference, above the door in the front
of the furnace, and in this end of the tube 6 there is a rose or spreader formed
by a number of small holes 62, through which the superheated steam together
with atmospheric air passes into the furnace.
Figures 4 and 5 show longitudinal sections of hollow fire-bars for super-
heating steam before admitting it into a furnace. In each of these fire-bars
there is one large hollow space a, in which the steam is superheated; the
steam is admitted into this space through the small passage b, which passes
underneath the space a almost from end to end of the fire-bar, steam being
admitted through the pipe c into one end of the passage b, and the other end
of the passage b communicating through an opening d, with one end of the
space a, at the other end of the space a there is a pipe e, which conducts the
superheated steam into the furnace above the fuel on the fire-bars. The
opening d is made by first making a hole f through the upper or lower part
of the fire-bar, which hole is afterwards closed. In place of making the
small passage b through the fire-bar, steam may be admitted into the end of
the space a through a separate tube passing under the fire-bar. In place
of the steam-passing through only one fire-bar, it may be caused to pass
through two or more before entering the furnace.
Figure 6 shews. a section of three hollow fire-bars a, b, and c, combined
together so as to cause the steam before it enters the furnace to pass through
each of thein. The steam is first introduced through the pipe d into one-end
of the hollow fire-bar a, and at the other end of the fire-bar a there is a pipe e

page_text: which communicates with one end of the fire-bar b, the other end of the fire-
bar 6 communicating in like manner by a pipe f, with one end of the fire-bar
c; and at the other end of the fire-bar c there is a pipe g, which conveys the
superheated steam into the furnace.
Figure 7 shows a section of the furnace and fire-box of a locomotive, and
Figure 8 shews a section of the furnace of a marine steam boiler, having
hollow fire-bars for superheating steam applied thereto. In each of these
Figures the same letters of reference refer to the same parts. Steam is
admitted from the boiler, or if the steam in the boiler is not at a sufficient
pressure to obtain the desired results from a small auxiliary boiler, in which
the steam is at a greater pressure (say 5, 10, or 15 atmospheres) through
the pipe or passage a to the hollow fire-bar, and after having passed through
the hollow fire-bar it passes away through the pipe b into the furnace at the
points c and d through roses or spreaders, which direct it on to the surface of
the fuel; or, if it is preferred, the steam may only be admitted at one point,
or it may be admitted at more points, and it may either be mixed with air,
as above described, or not, as desired.
Figure 9 shews another section of the furnace of a marine steam boiler
having hollow fire-bars for superheating steam applied thereto. Steam is
admitted through the pipe a to the hollow fire-bar b, it then passes through
the hollow fire-bar c, and then through the fire-bar d, it then passes into the
pipe e through the holes f, f, in which it escapes into the furnace. And I
would remark that, although I have here shewn the hollow fire-bars only
applied to the furnace of a locomotive and of a marine steam boiler, they may
be applied to all kinds of furnaces.
Figure 10 shews a horizontal section of a furnace having chambers a, b,
formed at its side, through which the steam passes before it enters the
furnace. These chambers are formed of iron, and the sides of the chambers
next the fire are protected by fire-bricks, as shewn. The steam first enters
one end of the chamber a through the pipe c, and at the other end of the
chamber a there is a pipe d, through which the steam passes into one end of
the chamber b; in the other end of this chamber there is a pipe e, through
which the steam passes into the furnace, as shewn; c', c', are plugs or taps
for facilitating the cleansing of the apparatus. When the chambers a and b
require to be repaired they may be withdrawn from the back of the furnace
without extinguishing the fire.
Figures 11, 12, 13, 14, and 15 shew sections of different shapes of roses or
spreaders for introducing superheated steam into furnaces; they are cach

page_text: formed of a tube or case having a number of small holes a, a, formed at one
end. Steam is introduced into the other end of each spreader through a
pipe d, and it passes out through the holes a, a, into the furnace. These
roses or spreaders are placed by preference above the fuel on the fire-bars, so
that the jets of steam are directed at an angle on to the surface of the fuel.
Figure 16 shews another spreader which consists of a tube in which there
are holes a, a, through which the steam passes into the furnace, steam being
supplied to this tube through the pipe b; this tube is furnished with plugs or
cocks at c and d to facilitate the cleansing of the apparatus.
In witness whereof, I, the said Jean Baptiste Pierro Alfred Thierry,
have hereunto set my hand and seal, this Twelfth day of January, in
the year of our Lord One thousand eight hundred and fifty-nine.
JEAN BAPTISTE PIERRE ALFRED THIERRY, FILS. (L.S.)
Paris, le Douze Janvier, 1858.