IMPROVEMENTS IN STEAM: BOILERS
Year: 1860

page_text: LETTERS PATENT to James Petrie, of Rochdale, in the County of
Lancaster, Engineer, for the Invention of "IMPROVEMENTS IN STEAM:
BOILERS."
Sealed the 12th March 1861, and dated the 14th September 1860.
PROVISIONAL SPECIFICATION left by the said James Petrie at the
Office of the Commissioners of Patents, with his Petition, on the
14th September 1860.
I, JAMES PETRIE, of Rochdale, in the County of Lancaster, Engineer, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN STEAM
BOILERS," to be as follows:-
My Invention has for its object the extension of heating surface in the flues
of boilers. To the periphery of the flue I attach bent pieces of metal con-
stituting chambers, which are open to the water. The description of chamber
to which my Invention refers may be illustrated by supposing a circular piece-
of metal to be bent and fixed to the flue, through which an opening or
openings are formed at the included part. These chambers I place at an
angle to the horizontal line, and I also employ a series of them one behind
another placed at opposing angles alternately.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said James Petrie in the Great Seal Patent Office on the
14th March 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
PETRIE, of Rochdale, in the County of Lancaster, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourteenth day of September, in the year of our
Lord One thousand eight hundred and sixty, in the twenty-fifth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said James Petrie, Her especial license that I, the said James
Petrie, my executors, administrators, and assigns, or such others as I,
the said James Petrie, 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-
PROVEMENTS IN STEAM BOILERS," upon the condition, amongst others, that
I, the said James Petrie, by an instrument in writing under my band and
seal, should particularly describe and ascertain the nature of the said Inven-
tion, 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 James Petrie, 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 and accompanying Drawings (that is to say):-
-
Fig. 1 is a cross section of a boiler taken through the flues; and Fig. 2 is
a side view of one of the flues; Figs. 3, 4, 5, 6, are sections of the flue, taken
respectively in the lines A, B, C, D, but drawn upon a smaller scale, in order
that they may be placed over the lines along which the sections are taken.
The shell of the boiler is at a, and the two flues at b, b. To: the inward cir-
cumference of these flues are attached water chambers c, c¹, c, c, which are in
communication with the boiler by means of openings d, e, f. Each of these
chambers is placed at an angle to the horizontal line, so that a circulation of
water through them is promoted, and any solid matters which may accumulate
will fall through them. On looking at Fig. 1 it would appear that the area
for the passage of the products of combustion is narrowed to the rectangular
opening there seen, but this is avoided by placing the water chambers c, c, c², c³,

page_text: at some distance behind each other. Thus the chamber shewn at c, Fig. 1, is
situate at A, Fig. 2, and those at c², c, c³, at B, C, D. The manner in which
the water chambers are disposed around the interior of the flue will be under-
stood by inspecting Figs. 3, 4, 5, 6, which are sections corresponding to the
lines A, B, C, D. Thus it will be seen that a continuous stay is formed
around the flue, and an extended heating surface is obtained, around which
the products of combustion lap as they pass from the furnace. The manner
in which I construct the water chambers is shewn at Fig. 7, 8, 9, the first of
these shews an oval disc of metal, which I bend or double into the form shewn
at Fig. 8; a flange is then formed upon it, as at Fig. 9, and it is ready to be
attached thereby to the flue.
I have above described a particular method of arranging the water chambers
around the flue, but I do not confine myself thereto, as variations may be made
therein if desired; for instance, they may be placed as at Fig. 10, and behind
each other, as before described; or as another example of part of my Invention,
they may be disposed as at Fig. 11. I have also shewn a certain number of
these chambers to each flue, but they may be more or less as desired, and it
will, of course be understood, that a single flue boiler may be constructed
according to my Invention if desired.
Having thus described and ascertained the nature of my said Invention, and
the manner of carrying the same into effect, I desire it to be understood that
I claim as secured to me under the above in part recited Letters Patent,-
Firstly, forming a water chamber or chambers of the character above shewn
and described within the flue or flues of a boiler.
Secondly, placing water chambers within a flue or flues in series one behind
another, and at different angles.
In witness whereof, I, the said James Petrie, have hereunto set my
hand and seal, the Thirteenth day of March, in the year of our Lord
One thousand eight hundred and sixty-one.
JAMES PETRIE. (L.S.)