IMPROVEMENTS IN STEAM BOILERS
Year: 1869

page_text: "
LETTERS PATENT to George Francis Gabriel Desvignes, of Lower
Tulse Hill, in the County of Surrey, for the 'Invention of
"IMPROVEMENTS IN STEAM BOILERS."
Sealed the 20th July 1869, and dated the 9th February 1869.
PROVISIONAL SPECIFICATION left by the said George Francis Gabriel
'Desvignes at the Office of the Commissioners of Patents, 'with 'his
• Petition, on the 9th February 1869.
I, GEORGE FRANCIS GABRIEL DESVIGNES, of Lower Tulse Hill, in the
County of Surrey, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN STEAM BOILERS," to be as follows:-
This Invention has for its object improvements in steam boilers.
In constructing vertical boilers, that is to say, boilers in which the flue
rises from the crown of the fire-box and passes up through the water
space of the boiler, I increase the heating surface of the boiler, Bo s
to admit of steam being got.up rapidly by the application of syphon-like
pipes: inserted into the crown of the fire-box. Each pipe is fixed at one
endy into the crown of the fire-box, and after projecting a convenient
distance into the fire-box is bent round and led up again into the boiler,
[Price 8d.]
No text detected.

page_text: where it is made to ascend almost to the water level of the boiler; a
constant circulation then takes place in the syphon pipes so long as the
fire is burning, the heated water ascending by the longer leg of the
syphon, and the cooler water descending from the boiler by the shorter
leg. I would remark that the general principle of drawing water from
the lower part of the boiler and returning it to the upper part, causing it
intermediate of these parts to pass through a heated pipe, is no part of
my Invention, which consists only in the application of this principle to
vertical boilers in the manner which I have particularly described.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said George Francis Gabriel Desvignes in the Great
Seal Patent Office on the 7th August 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
FRANCIS GABRIEL DESVIGNES, of Lower Tulse Hill, in the County of
Surrey, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Ninth day of February, in the year of
our Lord One thousand eight hundred and sixty-nine, in the thirty-
second year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said George Francis Gabriel Desvignes,
Her special licence that I, the said George Francis Gabriel Desvignes,
my executors, administrators, and assigns, or such others as I, the
said George Francis Gabriel Desvignes, 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,
sbould 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 condition (amongst others) that I, the said George Francis
Gabriel Desvignes, 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.

page_text: : NOW KNOW YE, that I, the said George Francis Gabriel Desvignes,
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 thereof, that is to say :-
This Invention has for its object improvements in steam boilers. In
constructing vertical boilers, that is to say, boilers in which the flue rises
from the crown of the fire-box and passes up through the water space of
the boiler, I increase the heating surface of the boiler so as to admit of
steam, being got up rapidly by the application of syphon-like pipes
inserted into the crown of the fire-box. Each pipe is fixed at one end
into the crown of the fire-box, and after projecting a convenient distance
into the fire-box is bent round and led up again into the boiler,. when it
is made to ascend almost to the water level of the boiler; a constant
circulation then takes place in the syphon pipes so long as the fire is
burning, the heated water ascending by the longer leg of the syphon, and
the cooler water descending from the boiler by the shorter leg. I would
remark that the general principle of drawing water from the lower part
of the boiler and returning it to the upper part, causing it intermediate
of these parts to pass through a heated pipe, is no part of my Invention,
which consists only in the application of this principle to vertical boilers
in the manner which I have practically described.
In the Drawings hereunto annexed is shown a vertical steam boiler
constructed as above described.
Figure 1 shows a vertical section of the boiler; and Figure 2 a plan
view of the plate forming the crown of the fire-box; Figure 8 shows
full size a vertical section taken through a portion of this plate and
through one of the syphon tubes carried by it. These syphon tubes I
prefer to form of tubes of what is known as homogeneous iron, but they
might be of copper or other suitable metal. The tubes are bent at the
centre of their length, as shewn in the Drawing, so as to bring the two
ends of the tubes parallel with one another. The two ends of the tube
are passed through two adjacent holes in the plate forming the crown of
the fire-box. The holes in this plate are made conical, as shown, and the
ends of the tubes are expanded into them, and are thus fixed in position,
as is well understood. Other arrangements for fixing the ends of the tubes
to the crown of the fire-box might however be adopted. When the tubes
have thus been fixed to the crown plate a lengthening tube formed with
a funnel mouth is driven into one end of each tube, and this tube may

page_text: extend to any height desired into the boiler so long as its upper end is
below the lowest water level of the boiler. The form to which I prefer
to curve the several syphon tubes to ensure that the products of com-
bustion as they pass to the central vertical flue or chimney shall of
necessity pass in close proximity to some of the syphon tubes is clearly
shown at Figure 1. This Figure also shews in detail the manner in
which I prefer to construct the vertical boiler and its fire-box, but I do
not limit myself to these details of construction.
In witness whereof, I, the said George Francis Gabriel Desvignes,
have hereunto set my hand and seal, this Fifth day of August, in
the year of our Lord One thousand eight hundred and sixty-
nine.