AN IMPROVED TUBULAR STEAM GENERATOR
Year: 1858

page_text: LETTERS PATENT to Louis Durand, of Marseille, a Town in the French
Empire, Civil Engineer, for the Invention of "AN IMPROVED TUBULAR
STEAM GENERATOR."
Sealed the 9th November 1858, and dated the 12th May 1858.
PROVISIONAL SPECIFICATION left by the said Louis Durand at the Office
of the Commissioners of Patents, with his Petition, on the 12th May
1858.
I, LOUIS DURAND, of Marseille, a Town in the French Empire, Civil
Engineer, do hereby declare the nature of the said Invention for "AN IMPROVED
TUBULAR STEAM GENERATOR," to be as follows:-
The object of my Invention is to provide an apparatus which may be sub-
stituted with many advantages for the ordinary arrangement of tubes used in
multitubular steam boilers, and my Invention consists of a steam generator
composed of one upper and two lower longitudinal tubes of comparatively
large diameters, and communicating with each other by means of a number of
very small tubes arranged side by side transversely and in a serpentine or
zig-zag form. The lower ends of one half of the small tubes terminate
in each of the lower longitudinal tubes, and the upper ends of the whole
terminate in the upper longitudinal tube. The upper and lower longitudinal
tubes are each furnished with valves opening upwards only, in order that the
feed water on being forced into the lower tubes may be compelled to traverse
the same, pass through the series of small tubes to the large upper tube, and

page_text: finally pass out of the said upper tube into the boiler itself, from which the
steam is taken as required. The longitudinal and transverse tubes before
described may be strengthened by the addition of any suitable stay or of a
frame, so as to constitute a steam generator, which may be passed bodily into
the fire box and flues of any form of boiler, and occupy the place of the
ordinary tubes, which are dispensed with. Any number of boilers thus
furnished may be combined as may be required. One end of each of the
longitudinal tubes is fitted with a screw cap that may be taken off when it is
necessary to examine or cleanse them. The number of such tubes may
be varied, and the arrangement of the transverse tubes modified accordingly.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Louis Durand in the Great Seal Patent Office on the 12th
November 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, LOUIS
DURAND, of Marseille, a Town in the French Empire, Civil Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twelfth day of May, in the year of our Lord
One thousand eight hundred and fifty-eight, in the twenty-first year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Louis Durand, Her special licence that I, the said Louis
Durand, my executors, administrators, and assigns, or such others as I,
the said Louis Durand, 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 "AN
IMPROVED TUBULAR STEAM GENERATOR," upon the condition (amongst others)
that I, the said Louis Durand, my executors or adıministrators, by an instru-
ment 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 imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Louis Durand, do hereby declare the
nature of my said Iuvention, and in what manner the same is to be performed,

page_text: 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:-
The object of my Invention is to provide an apparatus which may bo
substituted with many advantages for the ordinary arrangement of tubes used
in multitubular steam boilers, and my Invention consists of a steam generator
composed of one upper and two lower longitudinal tubes of comparatively large
diameters, and communicating with each other by means of a number of very
small tubes arranged side by side transversely and in a serpentine or zig-zag
form. The lower ends of one half of the small tubes terminate in each of the
lower longitudinal tubes, and the upper ends of the whole terminate in
the upper longitudinal tube. The upper and lower longitudinal tubes are
each furnished with valves opening upwards only, in order that the feed water
on being forced into the lower tubes may be compelled to traverse the same,
pass through the series of small tubes to the large upper tube, and finally pass
out of the said upper tube into the boiler itself, from which the steam is taken
as required. The longitudinal and transverse tubes before described may be
strengthened by the addition of any suitable stays, or of a frame, so as to
constitute a steam generator, which may be passed bodily into the fire box and
flues of any form of boiler and occupy the place of the ordinary tubes, which
are dispensed with. Any number of boilers thus furnished may be combined
as may be required. One end of each of the longitudinal tubes is fitted with
a screw cap that may be taken off when it is necessary to examine or cleanse
them. The number of such tubes may be varied and the arrangement of the
transverse tubes modified accordingly.
My Invention is illustrated in the Drawings hereunto annexed. Figure 1
is a side view of the improved apparatus detached from a boiler; the upper
tube a, which is shewn separately in Figure 2, is furnished with short tubular
pieces c, e, into which the upper ends of the transverse small tubes c, c, are
fitted; b, b, are the two lower tubes, which are fitted with similar pieces c¹, c¹,
and receive the lower ends of the said tubes c, c.
Figure 3 shews part of a locomotive with my apparatus partially inserted;
Figure 4 is a longitudinal section of the locomotive with the apparatus in its
place; Figure 5 is a transverse section of the locomotive near the chimney;
Figure 6 is a similar section near the fire; Figure 7 indicates an end view;
Figure 8 is a front view, partly in section, of a group of marine boilers, each
fitted with the apparatus; Figure 9 is an end view of the same partly in
section.
In the two latter Figures E is the feed pipe; C, the pipe by which the

page_text: water in the several boilers may flow from one to the other; B is the steam
pipe, common to all the boilers and steam reservoirs; A is the steam supply
pipe, and F, F, F", are cocks by which the water or steam from any one
boiler may be intercepted at will for repairs or otherwise. The tubes a, b, b,
(Figures 1 to 4) are connected with the interior of the boiler by means of
.strong short tubes d, d. The method of arranging the several tubes and
of fitting them with valves, stays, or frame screw caps, &c., is described above.
I form the several parts of any suitable material or materials, but I prefer to
employ copper for the small tubes c, c, and brass or mixed metal for the large
pipes, valves, and screw caps. The size and form of the small tubes are such
that a very large heating surface is obtained, and continual currents are kept
up throughout them.
And having now described the nature of the said Invention, and in what
manner the same is to be performed, I declare that I claim the construction
of a steam generator applicable to boilers of all descriptions, composed of one
upper and two lower longitudinal tubes of comparatively large diameters, and
communicating with each other by means of a number of very small tubes
arranged side by side and in a serpentine form, essentially as herein-before
described.
In witness whereof, I, the said Louis Durand, havo hereunto set my
hand and seal, this Fifth day of November, One thousand eight
hundred and fifty-eight.
Witness,
Cu. ARMENGAUD, Ing" Civil,
23, Boulevard de Strasbourg,
à Paris.
LOUIS DURAND. (L.S.)