IMPROVEMENTS APPLICABLE TO STEAM BOILERS FOR ECONOMISING FUEL
Year: 1863

page_text: LETTERS PATENT to Thomas Hall, of Oldham, in the County of Lan-
caster, Engineer, for the Invention of "IMPROVEMENTS APPLICABLE TO STEAM
BOILERS FOR ECONOMISING FUEL."
Sealed the 17th June 1864, and dated the 28th December 1863.
PROVISIONAL SPECIFICATION left by the said Thomas Hall at the
Office of the Commissioners of Patents, with his Petition, on the 28th
December 1868.
I, THOMAS HALL, of Oldham, in the County of Lancaster, Engineer, do
hereby declare the nature of the said Invention for "IMPROVEMENTS APPLICABLE
TO STEAM BOILERS FOR ECONOMISING FUEL," to be as follows:-
My improvements consist in making the exterior flues of steam boilers of
iron water tanks or chambers, so that the heat which is wasted in the ordinary
method of constructing the flues of brickwork will be advantageously applied
for heating the feed water of the boiler and for generating steam. My
Invention is applicable to every description of steam boiler in which exterior
flues are employed.
In applying my improvements to a cylindrical boiler with internal flues, I
apply at the end of the boiler an iron water tank or chamber, in which is a
curved recess (either with or without tubes) to collect the products of com-
bustion from the internal flues, and convey them to a flue or flues passing
under the boiler; they then ascend into side flues formed by the water tanks
or chambers, which side flues are in communication with the chimney or with

page_text: other tanks placed outside the end tank above referred to. The water tanks
or chambers may all be in communication with each other or otherwise, and
the pump for forcing the feed water into the boiler may draw its water from
any of the tanks, or the steam generated in the tanks may be employed for
heating or other purposes. The above details must be varied according to
the peculiar construction of the boiler to which my improvements are
applied.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Hall in the Great Seal Patent Office on the 25th
June 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
HALL, of Oldham, in the County of Lancaster, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-eighth day of December, in the year of
our Lord One thousand eight hundred and sixty-three, in. the twenty-seventh
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said Thomas Hall, Her special license that I, the said
Thomas Hall, my executors, administrators, and assigns, or such others as
I, the said Thomas Hall, 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
nake, use, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS APPLICABLE TO STEAM BOILERS FOR ECONOMIZING FUEL," upon the
condition (amongst others) that I, the said Thomas Hall, 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 Thomas Hall, do hereby declare the
pature of my 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 (that is to say):-
My improvements consist in making the exterior flues of steam boilers of

page_text: iron water tanks or chambers, so that the heat which is wasted in the ordinary
method of constructing the flues of brickwork will be advantageously applied
for heating the feed water of the boiler, and for generating steam. My
Invention is applicable to every description of steam boiler in which exterior
flues are employed.
In applying my improvements to a cylindrical boiler with internal flues, I
apply at the end of the boiler an iron water tank or chamber, in which is a
curved recess (either with or without tubes) to collect the products of com-
bustion from the internal flues, and convey them to a flue or flues passing
under the boiler; they then ascend into side flues formed by the water tanks
or chambers, which side flues are in communication with the chimney or with
other tanks placed outside the end tank above referred to. The water
tanks or chambers may all be in communication with each other or other-
wise, and the pump for forcing the feed water into the boiler may draw its
water from any of the tanks, or the steam generated in the tanks may be
employed for heating or other purposes. The above details must be varied
according to the peculiar construction of the boiler to which my improvements
are applied.
And in order that my Invention may be fully understood and readily carried
into operation, I will proceed to describe the accompanying Sheet of Drawings,
reference being had to the figures and letters marked thereon.
Figure 1 is a side elevation in section; Figure 2 is a transverse section,
and Figure 3 a plan of an ordinary two-flued cylindrical boiler to which my
improvements are applied.
.
a is the outer shell of the boiler; b, b, the internal flues; c, the flue passing
under the boiler into the side flues d, d; these side flues unite previous to
entering the chimney e. The fire grates are or may be placed as usual in
the internal flues b, b, and when the products of combustion arrive at the end
of these flues, they are collected and united in the curved recess f¹ of the
tank or chamber f, which is made of boiler plate iron, and contains water;
this tank or chamber is connected by the pipes 9, 9, to the semicircular
tank h, the ends of which are connected to the side tanks i, i, by the elbow
pipes j,j. The water supplied to the tanks f, h, and i is heated by the
products of combustion passing through the flues 6 and d to the chimney e,
and the heated water may be used as feed water for the boiler a.
The pipes
g and j, above referred to, allow the water to circulate from one tank to the
other, and the steam generated in the tanks may be employed for heating or
other purposes.
The pipes k, shewn by dotted lines in Figure 1, pass from the under part

page_text: of the tank f into the flues b, b, and then into the upper part of the tank f;
the water circulating through these pipes is considerably heated by the products
of combustion passing through the flues b, b, and is discharged into the upper
part of the tank f. The number and arrangement of these parts may be
considerably varied.
The water tanks are or may be provided with safety valves and glass tubes
to indicate the level of the water and the pressure of the steam or other
suitable apparatus to prevent injury and explosions. By means of these
improvements the heat which is absorbed and wasted in the ordinary method
of constructing the flues of brickwork is advantageously applied, thus econo
mizing fuel to a great extent.
Having thus stated the nature of my Invention, and described a convenient
manner of performing the same, I wish to remark that I do not limit myself
to the details given, as the peculiar arrangement and construction of the water
tanks or chambers may be varied according to the form of the boiler and the
arrangement of the flues; and I declare that I claim making the exterior
flues of steam boilers of water tanks or chambers for economizing fuel, as
described, or any modification thereof. I also claim the circulation pipes
marked K, in Figure 1, when applied in the manner described.
In witness whereof, I, the said Thomas Hall, have hereunto set my
hand and seal, this Twenty-fourth day of June, One thousand eight
hundred and sixty-four.
HO