IMPROVEMENTS IN STEAM BOILERS
Year: 1855

page_text: LETTERS PATENT to John Lee Stevens, of Fish Street Hill, in the City of
London, Civil Engineer, for the Invention of "IMPROVEMENTS IN STEAM
BOILERS."
Sealed the 25th January 1856, and dated the 10th August 1855.
PROVISIONAL SPECIFICATION left by the said John Lee Stevens at the
Office of the Commissioners of Patents, with his Petition, on the 10th
August 1855.
I, JOHN LEE STEVENS, of Fish Street Hill, in the City of London, Civil
Engineer, do hereby declare the nature of the Invention for "IMPROVEMENTS
IN STEAM BOILERS " to be as follows:-
This Invention consists of a peculiar combination of the parts of a steam
boiler where tubular flues are employed, whereby atmospheric air is more
advantageously applied and combined with the products of combustion than
heretofore. For this purpose, in constructing a steam boiler with internal
fire-places there is formed a water space above the furnace or furnaces, and
above this water space is a return flue or flues, through which the products of
combustion from the furnace or furnaces pass to a chamber, which may
be called the igniting box. From this chamber or igniting box the tubular
flues pass to a chamber at the opposite end of the boiler. In the front of the
igniting chamber is an opening, which is covered by a double door or cover,
provided with numerous holes or passages, through which numerous streams of
air pass to the igniting chamber, and mix with the products of combustion
before they pass to or through the tubular flues. At the back there is a door
lined with fire brick; hence the tubular flues are accessible at both ends, and
may readily be cleaned.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Lee Stevens in the Great Seal Patent Office on the
9th February 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN LEE
STEVENS, of Fish Street Hill, in tlie City of London, Civil Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Tenth day of August, in the year of our Lord
One thousand eight hundred and fifty-five, in the nineteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said John Lee Stevens, Her special licence that I, the said John Lee
Stevens, my executors, administrators, and assigns, or such others as I, the said
John Lee Stevens, 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, exer-
cise, 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 condition (amongst others) that I, the said John Lee
Stevens, 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 John Lee Steveus, 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 in a peculiar combination of the parts of a steam
boiler where tubular flues are employed, whereby atmospheric air is more
advantageously applied and combined with the products of combustion than
heretofore. For this purpose, in constructing a steam boiler there is formed a
water space above the furnace or furnaces, and above this water space a return
flue or flues, through which the products of combustion from the furnace or
furnaces pass to a chamber, which may be called the igniting box. From this
chamber or igniting box the tubular flues pass to a chamber flue or up-take at
the opposite end of the boiler. In the front of the igniting chamber is an
opening, which is covered by a double door or cover, provided with numerous

page_text: holes or passages, through which numerous streams of air pass to the igniting
chamber, and mix with the products of combustion before they pass to or
through the tubular flues. At the back there is a door lined with fire brick;
hence the tubular flues are accessible at both ends, and may be readily cleaned.
The manner in which I perform the same in steam boilers with internal fire-
places is shown by the Drawings accompanying this.
Figure 1 is a transverse section; Figure 2, a longitudinal section; and
Figure 3, a plan. a, a, a, fire-places or furnaces; b, b, b, water spaces above
the furnaces; c, c, c, c, c, c, c, c, other water spaces in the boiler; d, d, d,
return flues or tubes; e, e, e, combustion chambers or igniting boxes;
ffffff, tubes or flues passing to the up-take chamber at the back of the
boiler; g, g, g, up-take chamber leading to funnel; h, h, h, perforated doors
for the admission of air; i, i, i, i, course of the products of combustion; j, j, j,
direction of atinospheric air to complete the ignition of the products of com-
bustion; k, k, door at the back of the tubes; 1, 1, man-hole for access to the
up-take chamber, when preferred to the door k; and the manner in which I
apply my Invention to steam boilers with external fire-places is shown in the
transverse and longitudinal Figures 4 and 5, to both of which the correspond-
ing letters of reference previously given will be found to apply.
I make no claim to the several parts respectively mentioned when separately
considered, nor to the diverse traversing of flues or tubes through steam
boilers; but what I do claim is, the peculiar arrangement of the parts of
steam boilers herein set forth, so as to form combustion or igniting chambers
or boxes in front of the boilers, such chambers being separated by flues or
tubes from the furnace thereof, and supplied with atmospheric air to mix
with the products of combustion within those chambers, in the manner
described.
In witness whereof, I, the said John Lee Stevens, have hereunto set my
hand and seal, this Seventh day of February, in the year of our Lord
One thousand eight hundred and fifty-six.
Witness,
V. CARPMAEL.
JOIN LEE STEVENS. (L.S.)