IMPROVEMENTS IN STEAM BOILERS
Year: 1872

page_text: LETTERS PATENT to Walter Edes, of Edinburgh, in the County of
Mid Lothian, North Britain, for the Invention of "IMPROVEMENTS IN
STEAM BOILERS."
PROVISIONAL SPECIFICATION left by the said Walter Edes at the
Office of the Commissioners of Patents, with his Petition, on the
19th September 1872.
I, Walter Edes, of Edinburgh, in the County of Mid Lothian, North
Britain, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN STEAM BOILERS," to be as follows, that is to say :-
This Invention has for its objects to simplify the construction of
steam boilers, to reduce their cost, and to economise fuel by rendering
them more efficient.
The Invention consists principally in forming within the boiler a
species of reverberatory chamber or oven, into the front end of which
the flames or fire gases are admitted from a furnace, fire-box, or grate
of the ordinary construction. This chamber is made of a large size

page_text: relatively to the external dimensions of the boiler, and so as to comprise
an amount of heating surface which, taking into account the increased
efficiency it is expected to have, will correspond to that provided in
ordinary boilers by flues or tubes.
The exit from the chamber is formed in the side, top, or bottom, but
at or near the front or entrance end, which arrangement is an essential
and important feature of the Invention, its object bring to avoid the
rapid rushing of the flames or fire-gases directly through flues or tubes.
as in ordinary boilers, with which rushing action much of the heat is
carried wastefully to the chimney, whereas in the oven arrangement the
flames reverberate and circulate and have a better opportunity of
imparting their heat to the shell of the chamber.
The arrangement also prevents smoke as the current entering from
the furnace tends towards the further end of the chamber on one side
and returns slowly along the other side to the outlet, the returning
current mixing more or less with the freshly entering flames so that any
unconsumed carbonaceous particles become ignited. The outlet from
the chamber may be formed directly thence to the outside of the boiler
or it may communicate with a flue tube returning along inside the boiler
to its back end, and in either case flues may be continued in the ordinary
way in contact with the outside of the boiler.
The improvements are applicable to stationary, locomotive, or marine
boilers, and with various forms of the outer shell of the boiler.
In cases in which it is conveniently applicable a small additional flue
is made from the furnace or fire-box directly to the outer flue or chimney,
such additional flue being closed by a damper when the boiler is in full
work, but being opened when lighting the fire or when it is desired to
keep the fire barely alive without generating steam. A damper is fitted
in the main exit flue or outlet from the oven or reverberatory chamber
as a means for regulating or stopping the draught through that chamber.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Walter Edes in the Great Seal Patent Office on
the 21st February 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WALTER
EDES, of Edinburgh, in the County of Mid Lothian, North Britain, send
greeting
3

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Nineteenth day of September, in the
year of our Lord One thousand eight hundred and seventy-two, in
the thirty-sixth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Walter Edes, Her special
licence, that I, the said Walter Edes, my executors, administrators,
and assigns, or such others as I, the said Walter Edes, 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 " IMPROVEMENTS
IN STEAM BOILERS," upon the condition (amongst others) that I, the said
Walter Edes, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and scals, 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 Walter Edes, do hereby declare
the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by
the following statement in writing, reference being had to the accom-
panying Drawings, that is to say :-
My said Invention has for its objects to simplify the construction of
steam boilers, to reduce their cost, and to economise fuel by rendering
them more efficient than they are as ordinarily constructed.
My Invention consists principally in forming within the boiler a
species of reverberatory chamber or oven into one end of which the
flames or fire gases are admitted from a furnace, fire-box, or fire-grate
of the ordinary construction. This chamber is made of a large size
relatively to the external dimensions of the boiler and so as to comprise
an amount of heating surface which, taking into account the increased
efficiency I expect it to have, will correspond to that provided in
ordinary boilers by an elaborate and expensive combination of flues or
tubes.
The exit from the chamber is formed in the side, top, or bottom, but
at or near the front or entering end, which arrangement is an essential

page_text: and important feature of my Invention, its object being to avoid the
rapid rushing of the flames or fire gases directly through the flues or
tubes as in ordinary boilers, with which rushing action much of the
heat and unconsumed gases are carried wastefully to the chimney,
whereas in my improved arrangement the flames reverberate and
circulate and impart their heat in a better and more complete manner
to the shell of the chamber.
My improved arrangement also prevents smoke as the current entering
from the furnace tends towards the further end of the chamber, but
being arrested and having to return to the outlet the gases become
mingled, unconsumed portions become ignited, and the heat is morc
completely developed.
And in order that my said Invention and the manner of performing
the same may be properly understood, I hereunto append two Sheets of
explanatory Drawings, to be herein-after referred to, and representing
various modifications of steam boilers as made with my improvements.
In these Drawings the same reference numerals are used to mark the
same or like parts wherever they are repeated.
The Figures on Sheet 1 of the Drawings represent a boiler of a
horizontal cylindrical form, Figure 1 being a horizontal section, Figure 2
an end elevation, and Figure 3 a vertical section. In this example the
furnace or fire-grate 1 is arranged at the outer end of a cylindrical shell,
the part of which from the fire-bridge 2 to the inner end, marked
3, 4, constitutes the reverberatory chamber. The outlet 5 from the
chamber 3, 4, is at the front end immediately within the fire-bridge 2,
and it is by preference placed below the level of the bridge so that the
current of flames or fire gases does not sweep across it when proceeding
towards the inner end of the chamber. The outlet 5 leads to a short
longitudinal flue 6 extending to the front end of the boiler, and this
communicates with an upper longitudinal fluc 7 passing from the front
to the back end of the boiler, where it communicates with external flues
or with the chimney. The fire-bridge 2 is by preference made with
passages 8, as shown for the admission of air from the ash-pit 9 into the
reverberatory chamber therein to mingle with the fire gases and promote
more complete ignition and combustion. In some cases I prefer to
shape the furnace or grate space 1 so that its inner end is contracted
in width as shown in Figure 4 on Sheet 2 of the Drawings, this Figure
being a horizontal section of a modification of the horizontal cylindrical

page_text: boiler. This modification has the advantage of, as it were, placing the
outlet 5 still further aside from the current issuing from the furnace 1
into the chamber 3, 1. The outlet 5 from the chamber 3, 4, may be
made to proceed by a longitudinal flue 7 to the back end of the boiler,
as shown in Figure 4, or it may proceed directly across to and out at the
side of the boiler.
Figures 5 and 6 are diagrams showing as in vertical section modes in
which my reverberatory chamber 3, 4, may be arranged in boilers of a
vertical, cylindrical, or similar form.
My improvements are applicable to stationary, locomotive, and marine
boilers with various forms of the outer shell, the chamber 3, 4, being
modified in shape to correspond with the outer shell, and being in general
made as large as the outer shell will admit of, along with a suitable
space for the water.
Having thus particularly described my said Invention, and the manner
in which the same is to be performed, I have to state that I do not
restrict myself to the precise details herein described or delineated; but
that what I believe to be novel and original and claim as the Invention
secured to me by the hercin-before in part recited Letters Patent is, the
constructing of a steam boiler with a reverberatory chamber having an
entrance for the flames or fire gases at one end, and an outlet in the
side, top, or bottom near the entrance end, substantially in the improved
manner and for the purposes herein-before described.
In witness whereof, I, the said Walter Edes, have hereunto set
my hand and scal, this Eighteenth day of February, in the year
of our Lord One thousand eight hundred and seventy-three.
WALTER EDES. (L.S.)