IMPROVEMENTS IN THE GENERATION OF STEAM
Year: 1859

page_text: LETTERS PATENT to William Rowan, of the Firm of John Rowan &
Sons, Engineers, of Belfast, in the County of Antrim, for the Invention
of "IMPROVEMENTS IN THE GENERATION OF STEAM."
Sealed the 20th December 1859, and dated the 20th June 1859.
PROVISIONAL SPECIFICATION left by the said William Rowan at the
Office of the Commissioners of Patents, with his Petition, on the
20th June 1859.
I, WILLIAM ROWAN, of the Firm of John Rowan & Sons, Engineers, of
Belfast, in the County of Antrim, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE GENERATION OF STEAM," to be as
follows:-
This Invention consists of apparatus for superheating or desiccating the steam
after it has left the boiler, whereby the particles of water held in suspension
in the steam are themselves converted into steam. For this purpose I
construct a cylindrical tube of metal, and inside of this place another tube
somewhat smaller, so as to leave an annular space between the two. This
vessel is placed in the flue or chimney of a boiler, either for land or marine
engines, and the steam from the boiler is caused to pass through the above-
named annular space, whereby it. receives an additional charge of heat from
the products of combustion conveyed through the inner and outside the outer
tube in contact with its inner and outer surfaces.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Rowan in the Great Seal Patent Office on the 20th
December 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ROWAN, of the Firm of John Rowan and Sons, Engineers, of Belfast, in the
County of Antrim, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twentieth day of June, in the year of our Lord
One thousand eight hundred and fifty-nine, in the twenty-third year of
Her reign, did, for Herself, Her heirs and successors, give and grant
unto me, the said William Rowan, Her special licence that I, the said
William Rowan, my executors, administrators, and assigns, or such others
as I, the said William Rowan, 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 THE GENERATION OF STEAM," upon the condition (amongst
others) that I, the said William Rowan, 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 William Rowan, do hereby declare the
nature 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 thereof, reference being had to the Drawings hereunto annexed,
that is to say :-
This Invention consists of apparatus for superheating or desiccating the
steam after it has left the boiler, whereby the particles of water held in
suspension in the steam are themselves converted into steam. For this
purpose I construct a cylindrical tube of metal, and inside of this place
another tube somewhat smaller, so as to leave an annular space between the
This vessel is placed in the flue or chimney of a boiler either for land
or marine engines, and the steam from the boiler is caused to pass through
the above-named annular space, whereby it receives an additional charge of
two.

page_text: heat from the products of combustion conveyed through the inner and outside
the outer tube in contact with its inner and outer surfaces.
In the annexed Drawings, Figure 1 is a transverse section of an apparatus
constructed for carrying out my improvements; Figure 2 is a ground plan of
the same. The same letters of reference apply to like parts of each of these
Figures.
A, A, is the upper part or steam space of a marine or other boiler, and
B, B, the chimney through which the heated products of combustion escape
to the atmosphere; C, C, are two metallic cylinders placed concentrically one
within the other with a ring D, D, between them at each end, thus enclosing
between the said cylinders an annular steam-tight space or chamber; E¹, E³,
are partitions extending the whole length of the annular chamber, and dividing
it into separate and distinct compartments; .F', F, are partitions extending
from the bottom of the annular chamber to such a distance from the top
thereof as shall allow sufficient passage for the current of steam between the
top of these partitions and the top of the chamber; G¹ and G2 are ports or
passages connecting the steam space of the boiler with the annular chamber;
and H1, H2, are corresponding ports or passages connecting the annular
chamber with the steam pipes I, I, leading to the engine; J, J, are clearing
doors, by means of which any deposit that may be formed in the annular
chamber can from time to time be removed.
The steam issuing from the boiler through the passages G¹, G², ascends to
the top of the chamber, and passing over the partitions F¹, F³, descends again
to the bottom of the chamber, from whence it is conveyed to do its duty in the
engine by the pipes I, I. The chamber being placed in the midst of the
heated products in the chimney, both its inner and outer surfaces are heated,
and this heat is imparted to the current of steam circulating within.
The apparatus thus described applies to cases where two distinct marine
boilers are connected together, and having, consequently, two distinct steam
pipes. In other cases, where there is but one steam pipe, I omit the passages
Gs and H³, and also the partitions E¹, E²; or otherwise I make the partition E¹
to extend from top to bottom of the chamber, and F, F, stopping short of
the top as before described; and the partition E' I make to extend from the
top to a short distance from the bottom, the passages H', H2, being omitted,
but the other two retained. The direction of the current of steam, after
entering through G', will then be over the top of F¹, under E', over F³, and
finally out through the passage G³.
I have so far described my Invention as in connection with a marine

page_text: boiler, but it is equally well, adapted to a locomotive or other description of
boiler.
Having thus described the nature of my said Invention, and in what
manner the same is to be performed, I declare that I do not limit or confine
myself to the exact details herein-before referred to, as variations may be
made in the same without departing from the substantial features of my
Invention; and I declare that I claim as my improvements in generating
steam, the construction and employment of apparatus for superheating or
desiccating steam, essentially as herein-before described and represented in the
Drawings hereunto annexed.
In witness whereof, I, the said William Rowan, have hereunto set my
hand and seal; this Seventeenth day of December, One thousand
eight hundred and fifty-nine.
WILL". KOWAN. (L.S.)