IMPROVEMENTS IN STEAM BOILERS
Year: 1854

page_text: LETTERS PATENT to Thomas Stephen Holt and Charles Herbert Holt, of
the City of Manchester, in the County of Lancaster, Engineers, for the
PROVISIONAL SPECIFICATION left by the said Thomas Stephen Holt and
Charles Herbert Holt at the Office of the Commissioners of Patents,
with his Petition, on the 15th March 1854.
We, THOMAS STEPHEN HOLT and CHARLES HERBERT HOLT, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN STEAM BOILERS" to be
as follows:-
Behind the fire we propose to fix two plates, rivetted or jointed together so
as to leave a hollow space, and place a number of vertical tubes through the
said chamber, which tubes we propose to screw into the top and bottom plates.
The fire will pass from the furnace or fire hole over a bridge; it will then
descend under the said apparatus and, ascend through the vertical tubes, and
again descend, and ascend, as shewn in the accompanying Drawing. We
propose to place the said apparatus either longitudinally, as shewn in the
Drawing, or vertically, by which contrivance we expect to gain a considerable
saving of fuel, as well as consuming the smoke to a very great extent.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Stephen Holt and Charles Herbert Holt in the Great
Seal Patent Office on the 14th September 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, THOMAS
STEPHEN HOLT, and CHARLES HERBERT HOLT, of the City of Manchester, in
the County of Lancaster, Engineers, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Royal
Letters Patent, bearing date the Fifteenth day of March, in the year of our
Lord One thousand eight hundred and fifty-four, in the seventeenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto us, the
said Thomas Stephen Holt and Charles Herbert Holt, Her special licence that
we, the said Thomas Stephen Holt and Charles Herbert Holt, our executors,
administrators, and assigns, or such others as we, the said Thomas Stephen
Holt and Charles Herbert Holt, our 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 BOLLERS," upon the condition (amongst others) that we,
the said Thomas Stephen Holt and Charles Herbert Holt, by an instrument in
writing under our hands and seals, or under the hand and seal of one of us,
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 Royal Letters Patent.
• NOW KNOW YE, that we, the said Thomas Stephen Holt and Charles
Herbert Holt, 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 (that is to say):-
Our Invention consists of forming or constructing the boiler or vessel to
generate steam with two longitudinal tube plates, in which are placed an
indefinite number of small tubes in the centre of an ordinary flue having a
water space between them, thereby dividing the main flue into two separate
flues, which are again divided by stops into a number of combustion chambers.
The flame or heat passes alternately up and down the small tubes into the
different combustion chambers to the end of the boiler, and from thence into
the chimney, or otherwise through brick flues in the ordinary manner. By
this arrangement we gain additional heating surface, and the fiame or heat is

page_text: brought to bear on the water space more effectively, thereby generating a
greater amount of steam and reducing the quantity of fuel consumed. These
improvements will be clearly understood by reference to the accompanying
Sheet of Drawings, in which the same letters of reference are used to represent
the same parts in all the Figures.
Fig. 1 is an end elevation; Fig. 2, a longitudinal section; Fig. 3, a trans-
verse section; Fig. 4, a sectional plan of our improved fire-box boiler, with
the longitudinal tube plate extending from over the fire to the back end of the
boiler; Fig. 5 is an end elevation; Fig. 6, a longitudinal section; Fig. 7, a
transverse section; and Fig. 8, a sectional plan of our improved cylindrical
boiler, with the longitudinal tube plates extending from the back of the fire
bridge to the back end of the boiler; Fig. 9, a sectional plan; and Fig. 10, a
longitudinal section of an ordinary boiler with our stops applied to consume
the smoke and give the flame or heat a zigzag or undulating course; but
altho' we have only shewn plans of boilers with one fire and one flue, it is
evident we can apply our improvements to boilers with any number of fires or
flues, whether the said fires shall be placed only at one end of the boiler or
both ends, or in the centre. a represents the outer casing of the boiler; b, the
main flue; c, the longitudinal tube plates in the centre of the flue, dividing it
into two separate flues represented by d; the stays e are to strengthen the
tube plates; f, the water space; g, the stops; h, the fire doors; i, the grate
bars; j, the small tubes; and k, the air valve. It will be understood that the
flame or heat beating against the tube and flue plates, and traversing the
small tubes, communicates heat thereto, and evaporates the water which
surrounds them; and the said heat or flame from the fire passing through the
small tubes then meeting and concentrating in the first chamber causes a
combustion of the gases, then passing through the other small tubes and
meeting again in the different chambers causes a further combustion, thus
partially, if not entirely, consuming the smoke and effecting a very great saving
of fuel.
Having thus fully described the nature and particulars of our said Invention,
we desire it to be distinctly understood that we do not confine ourselves to the
exact details herein set forth, as such may be varied or modified without
departing from the principle thereof. But we claim as our Invention, and
which, to the best of our knowledge and belief, has not been hitherto used
within this realm,-
Firstly, the general arrangement and construction of boilers with longitudinal
tube plates and transverse tubes, placed either horizontally, vertically, or any
other convenient position.

page_text: And, secondly, the application of stops to give the flame or heat a zigzag
or undulating course through an ordinary flue, or to turn the flame or heat
from one flue to another alternately through transverse tubes, whether the said
stops be made of bricks; iron, or any other metal or material, as such improve-
ments are herein described and illustrated in the accompanying Sheet of
Drawings.
In witness whereof, we, the said Thomas Stephen Holt and Charles
Herbert Holt, have hereunto set our hands and seals, this Ninth day
of September, One thousand eight hundred and fifty-four.
i
(L.S.).
THOMAS STEPHEN HOLT.
CHARLES HERBERT HOLT. (L.S.)
Signed; sealed, and delivered by the
within-named Thomas Stephen Holt
and Charles Herbert Holt, in the
presence of
.
E. J. HUGHES,
Patent Agent,
Manchester.
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