IMPROVEMENTS IN STEAM AND OTHER BOILERS
Year: 1866

page_text: LETTERS PATENT to Thomas Green, of Leeds, in the County of York,
for the Invention of "IMPROVEMENTS IN STEAM AND OTHER BOILERS."
Sealed the 20th November 1866, and dated the 24th May 1866.
PROVISIONAL SPECIFICATION left by the said Thomas Green at the
Office of the Commissioners of Patents, with his Petition, on the 24th
May 1866.
I, THOMAS GREEN, of Leeds, in the County of York, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN STEAM AND OTHER
BOILERS," to be as follows:-
This Invention has for its object improvements in steam and other boilers.
The shell of the boiler, constructed according to this Invention, is a cylinder
placed in an upright position, and containing within it a fire-box of a conical
form. The base of the fire-box is nearly equal in diameter to the shell of the
boiler, and it is fixed to the lower end thereof. The fire-box tapers gradually
up to a point near or by preference a little below the water level of the boiler,
where it is fixed to the flue, which rises up from it through the upper end of

page_text: the cylinder into a short chimney supported on the top of the boiler. It is
preferred that the flue at its lower end where it joins the fire-box should be
smaller in diameter than at its upper end, so that the draft through the fire-
box and flue is most contracted just at the point where it leaves the fire-box; in
this way the heat is to a great extent concentrated within the fire-box, which
is entirely below the water level, this concentration of the heat tends to
prevent the escape of smoke, and also to prevent the flue from becoming
overheated. The fire-bars form the bottom of the fire-box, and the fire-door
is immediately above them. Horizontal tubes of comparatively large diameter
run through the fire-box from side to side, and communicate with the water
space of the boiler, these tubes serve both to stay the boiler and also to
increase the heating surface. The boiler is by preference mounted on a bed
plate of cast iron in which the ash-pit is formed; this bed plate is also made
hollow, and the space within it is employed for heating the feed water for the
boiler.
In making boilers for heating water for greenhouses and other uses the
construction of the fire-box and horizontal tubes is as above described, or the
fire-box may be of other horizontal section, but tapering, and the shell may
be of a cylindrical or other form.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Green in the Great Seal Patent Office on the
23rd November 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
GREEN, of Leeds, in the County of York, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fourth day of May, in the year of our Lord
One thousand eight hundred and sixty-six, in the twenty-ninth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Thomas Green, Her special licence that I, the said Thomas
Green, my executors, administrators, and assigns, or such others as I,
the said Thomas Green, 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 "Im-

page_text: PROVEMENTS IN STEAM AND OTHER BOILERS," upon the condition (amongst others)
that I, the said Thomas Green, my executors or administrators, by an instru-
ment 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 imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Thomas Green, 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 steam and other boilers.
The shell of a steam boiler constructed according to this Invention is a
cylinder placed in an upright position, and containing within it a fire-box of
a conical form. The base of the fire-box is nearly equal in diameter to the
shell of the boiler, and it is fixed to the lower end thereof. The fire-box
tapers gradually up to a point near or by preference a little below the water
level of the boiler, where it is fixed to the flue, which rises up from it through
the upper end of the cylinder into a short chimney supported on the top of the
boiler. The flue at its lower end where it joins the fire-box may be smaller
in diameter than at its upper end, so that the draft through the fire-box and
flue is most contracted just at the point where it leaves the fire-box, in this
way the heat is to a great extent concentrated within the fire-box, which is
entirely below the water level. This concentration of the heat tends to
prevent the escape of smoke, and also to prevent the flue from becoming
overheated. The fire-bars from the bottom of the fire-box and the fire-door
is immediately above them. Horizontal tubes of comparatively large diameter
run through the fire-box from side to side, and communicate with the water
space of the boiler; these tubes serve both to stay the boiler, and also to
increase the heating surface. The boiler is by preference mounted on a bed
plate of cast iron, in which the ash-pit is formed, this bed plate may also be
made hollow, and the space within it employed for heating the feed water for
the boiler.
Figure 1 is a vertical section of a steam boiler constructed according to
my Invention; Figure 2 is a horizontal section of the same taken at the
line 1, 1, Figure 1.
a, a, is the cylindrical shell of the boiler; b, the conical fire-box with its
smallest diameter at or somewhat below the water level, these parts are
.

page_text: rivetted together at their lower ends with a strengthening ring c between them,
and in connection with this ring the frame c' for the fire-door is formed;
d, d, are large water tubes passing through the fire-box, and secured to it by
flanges and rivets; e is a base plate which supports the fire-bars, and on which
the boiler stands, it may be made hollow for the circulation of the feed water,
but it is not so shown in this Drawing; f is the flue passing from the top of
the fire-box through the crown of the boiler; its smallest diameter is at its
lowest end. Figure 3 is a side view partly in section of a similar boiler, but
with some slight modifications; Figure 4 is a vertical section; and Figure 5
is a plan of the same; Figure 6 is a plan of the base plate; and Figure 7 is
an under side view of the boiler with the base plate removed. The letters of
reference correspond with the description already given at Figures 1 and 2,
as will be seen in this modification, greater capacity is given to the fire-box,
which however is still in its general form conical, with its smallest diameter
at or near the water line where the fluid joins it, the flue is represented of a
cylindrical form. The base plate is cast hollow to contain the feed water for
the boiler.
I claim as respects this part of my Invention the constructing boilers as
above described with the fire-box conical, and its smallest diameter at or near
the water line of the boiler.
Another part of my Invention relates to the construction of boilers for
heating water for greenhouses and other uses where the boiler is kept full of
water, and is connected with system of pipes in which the hot water cir-
culates. For this purpose the fire-box and horizontal tubes are arranged as
above described, or the fire-box may be of other horizontal section but tapering,
and the shell may be of any convenient form. Figure 8 is a front elevation;
Figure 9 is a vertical section; and Figure 10 is a plan of a boiler constructed
according to this part of my Invention. Boilers of this description may be
constructed either of wrought or cast iron, in the Drawings however cast iron
is indicated. a is the outer shell of the boiler with sockets a', a', for the inlet
and outlet pipes; bis the conical fire-box, which is connected by tap screws
with the casing a; c, c, are rings, which are interposed between the parts
a and b at the places where the fire-doors come, and these rings form the
frames for such doors; d, d, are water tubes passing through the fire-box, and
cast in one piece with it, or the tubes may be separate, and either of cast or
wrought iron; e, e, is the base plate on which the boiler and fire-bars are
supported; is the flue, which is connected to the top of the fire-box by a
casting, in which is a damper slide f. The outer casing of the boiler need

page_text: not taper, although this form is convenient, but it may be of any con-
venient form.
What I claim as respects this part of my Invention is the constructing
boilers such as above described with conical or tapering fire-boxes.
In witness whereof, I, the said Thomas Green, have hereunto set my
hand and seal, this Twenty-second day of November, in the year of
our Lord One, thousand eight hundred and sixty-six.
THOMAS GREEN. (L.s.)