IMPROVEMENTS IN STEAM BOILERS
Year: 1854

page_text: LETTERS PATENT to John Arrowsmith, of Bilston, in the County of
Stafford, Engineer, for the Invention of "IMPROVEMENTS IN STEAM
BOILERS."
Sealed the 28th November 1854, and dated the 1st June 1854..
PROVISIONAL SPECIFICATION left by the said John Arrowsmith at the
Office of the Commissioners of Patents, with his Petition, on the 1st
June 1854.
I, JOHN ARROWSMITH, of Bilston, in the County of Stafford, Engineer, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN STEAM
BOILERS to be as follows:-
My Invention consists of a boiler made of three tubular parts, set horizon-
tally in the furnace, the said furnace being double; the middle tubular part
of the boiler rests on the wall separating the two furnaces; the other two
tubular parts, which are smaller than the middle one, hang over the two
furnaces. All the three tubular portions are connected by vertical pipes with
a common steam chamber over and external to the furnaces. The central
tubular part of the boiler is hollow, that is to say, a flue runs through it, and
the fire and heated air from the furnaces, after having acted upon all sides of
the outer and smaller tubular parts of the boiler, and on the sides of the
middle tubular part, pass through the flue in the said middle tubular part to
the chinney. The ends of the outer and smaller tubular parts of the boiler

page_text: project from the front and back of the furnaces, and by removing lids or covers
therefrom, ready access can be obtained to the interior of the same for cleaning
or otherwise. Although I have described a boiler consisting of three tubular
portious, and heated by two furnaces, yet any number of sets of the said
tubular portions may be combined into a boiler, the number of the furnaces 5
being increased in the same ratio. I also sometimes use the waste heat of
puddling and mill furnaces to my improved boiler.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Arrowsmith in the Great Seal Patent Office on the.
1st December 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
ARROWSMITH, of Bilston, in the County of Stafford, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the First day of June, in the year of cur Lord One thou-
sand eight hundred and fifty-four, in the seventeenth year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said John
Arrowsmith, Her especial licence that I, the said John Arrowsmith, my executors,
administrators, and assigns, or such others as I, the said John Arrowsmith, 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 "IMPROVEMENTS IN STEAM BOILERS," upon the con-
dition (amongst others) that I, the said John Arrowsmith, by an instrument
in writing under my hand and scal, should particularly describe and ascer-
tain 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 John Arrowsmith, 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)
My Invention consists of a boiler, made in the manner illustrated in the

page_text: accompanying Drawing, Figure 1 representing a vertical transverse section of
a boiler constructed according to my Invention, and Figure 2 representing a
horizontal section of the same. It consists of the three tubular parts a, b, c,
the said tubular parts being set horizontally in the furnace d, e. The said fur-
nace is double, or divided into two parts by the wall or partition f; the middle
tubular part b rests on the wall f, which separates the furnaces d, e; the other
two tubular parts a, c, which are smaller than the middle one, as represented,
hang over the furnaces d, e, without any support underneath them. The three
tubular parts a, b, c, are connected by vertical pipes a', b, c, with the common
steam chamber g over and external to the furnaces d, e. The parts a, c, are
supported by the pipes 'a', c. A central flue h runs through the middle part b
of the boiler, and the fire and heated air from the furnaces, after having acted
on the sides and bottoms of the outer and smaller parts a, c, of the boiler, and
on the sides of the middle part b, the said flame and heated air pass along the
fluc h in the part b, and from thence to the chimney. The ends of the parts
a, c, of the boiler project from the front and back of the furnace, and by
removing lids or covers i, k, l, m, therefrom, ready access can be obtained to
the interior of the same, for cleaning or otherwise. Although I have described
and represented a boiler consisting of three tubular portions and heated by two
furnaces, yet any number of sets of the said tubular portions may be combined.
into a boiler, the number of the furnaces being increased in the same ratio; for
example, a tubular portion, similar to the part b, and resting on the wall of the
furnace, may be placed on the right of the part c, and another similar part on
the left of the part a, and thus any number of small and large tubular portions
may alternate with one another; each of the large parts resting on a wall
dividing the furnace, and one, two, or more of the transverse tubular steam
chambers g may be connected with the said tubular parts a, b, c. I sometimes
use the waste heat arising from puddling and mill furnaces used in the manu-
facture of iron, in place of or in addition to the heat of the steam boiler
furnace.
Having now described the nature of my said Invention, and the manner of
carrying the same into effect, I wish it to be understood that I do not limit
myself to the precise methods herein described, as the same may be varied
without departing from the nature of my said Invention; but I claim as my
Invention, the method herein-before described and represented in the accom-
panying Drawing, of constructing steam boilers, that is to say, connecting a
series of tubular boilers with tubular steam chambers, the said tubular
boilers being alternately large and small, the large boilers resting on walls

page_text: dividing or separating the furnaces, and having flues in their interiors, and the
smaller boilers being suspended in the furnaces without support underneath
them.
In witness whereof, I, the said John Arrowsmith, have hereunto set my
band and seal, this Thirtieth day of November, in the year of our Lord
One thousand eight hundred and fifty-four.
Witness,
GEORGE SHAW.
JOHN ARROWSMITH. (L.S.)