CERTAIN IMPROVEMENTS IN TUBES, PIPES, FLAGS, CURBS FOR PAVEMENT AND TRAMROADS
Year: 1849

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I Louis
PROSPER NICHOLAS DUVAL PIROU, Engineer, of Paris, send greeting.
WHEREAS, Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Sixteenth day of April,
One thousand eight hundred and forty-nine, in the twelfth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Louis Prosper Nicholas Duval Pirou, my exors, adñors, and assigns, Her
especial licence, full power, sole privilege, and authority, that I, the said
Louis Prosper Nicholas Duval Pirou, my exors, admors, and assigns, and
such others as I, the said Louis Prosper Nicholas Duval Pirou, my exors,
adriors, or assigns, should at any time agree with, and no others, from time
to time and at all times during the term of years therein expressed, should
and lawfully might make, use, exercise, and vend, within England, Wales, and
the Town of Berwick-upon-Tweed, and in the Islands of Guernsey, Jersey,
Alderney, Sark, and Man, and in all Her said Majesty's Colonies and
Plantations abroad, my Invention of "CERTAIN IMPROVEMENTS IN TUBES, PIPES,
FLAGS, CURBS FOR PAVEMENT AND TRAMROADS; in which said Letters Patent is

page_text: contained a proviso, that I, the said Louis Prosper Nicholas Duval Pirou,
should cause a particular description of the nature of my said Invention, and in
what manner the same is to be performed, by an instrument in writing under
my hand and seal, to be inrolled in Her said Majesty's High Court of
Chancery within six calendar months next and immediately after the date of
the said in part recited Letters Patent, as in and by the same, reference being
thereunto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Louis Prosper Nicholas Duval Pirou do hereby declare that the nature of the
said Invention, and the means of performing and carrying out the same, are
particularly described and ascertained by the following statement thereof,
reference being had to the Drawing hereunto annexed, and to the several
Figures therein contained, in which the same letters of reference in the different
Figures refer to similar parts, that is to say:-
My Invention consists in the construction of pipes, tubes, flags, curbs for
pavement and tramroads by inserting beton or concrete (a composition of
broken stones and hydraulic lime) between two surfaces of sheet iron. In
the Drawing hereto annexed, Figures 1, 2, and 3 represent the mode which I
have found the most eligible for the construction of a breakwater and pier.
When the water at low tide is about fifteen feet deep, I begin by setting up
two parallel rows of sheet iron pipes, four feet in diameter by eighteen feet
in height, I fill them up with concrete directly after I have properly placed
and secured them firmly together by cramps of iron or by any other convenient
means, so as to maintain them permanently in the vertical position I
have given them; I link them afterwards together at certain distances one
from the other by a number of similarly constructed pipes, which I set
transversally, as represented in Figure 1, so as to form by that mode of
adjuncting horizontal to vertical pipes, some compartments or castings which
I similarly fill up with concrete, until this last substance be on a level with the
several sides of the tubes forming the compartments or casings, as heroin
described; care being taken at the same time to surround the lower extremity
of the tubes with a circular band of linen cloth or any other suitable fabric
capable of preventing the escape of the concrete through the vacant spaces,
which the unevenness of the ground on which the vertical pipes are set might
naturally produce when the concrete is poured in. I construct the masonry
work which I raise above the foundation, herein-before described, in qutie a
different manner, that is to say, instead of placing the rows of tubes in a vertical
position, as herein-before described, I place them horizontally and leave them

page_text: entirely empty without filling them up with concrete as I have done for vertical
pipes; I take care, however, to fill up well with that substance the spaces which
separate one row from the other, and I proceed in that mode of construction
by setting regularly each successive layer of pipes one upon the other. These
layers are equal in thickness to the diameter of the pipes themselves, that is to
say, three feet and a half; and when that part of the work is completed the
tubes which are thus imbedded in the concrete present as many hollow
conducts through which the water can pass like through a sieve; by that
contrivance the action of the water is completely deadened. In Figures 2
and 3 the platform is surmounted by a parapet, being three feet and a half
high by three feet and a half wide. When I have to lay the foundation of a
work similar to that herein-before described on a mud or sand bottom, I use
instead of the tubes, prepared as herein-before described, tubes of a double
construction, that is to say, a tube enclosed in another of a larger diameter, as
represented by Figures 5 and 6. The empty space between the two sides of
the tubes is closed at its lower extremity and is filled up with concrete, so
that by digging level the sand or mud within the interior of the tube, the
weight of the last will be sufficient to sink it in until it reaches a sound
bottom; I fill up afterwards with concrete the empty space produced by the
removal of the sand or mud, and I proceed for the construction as I have
herein-before described in reference to Figure 1. When the sea in which I
have to construct the work instead of fifteen feet deep at low tide and of a
variable level is forty-eight feet deep with a constant level, I use the following
means by which the longitudinal sides of the compartments or casings produced
by the layers of tubes are obtained with two rows of tubes, as represented by
Figures 6, 7 and 8, and I proceed by setting level layers from twelve to
eighteen feet in thickness. When the first layer is levelled at about eighteen
feet above the bottom, the first row of tubes, constructed as herein-before
described, remains such as it is, but the second row is elongated of a quantity
similar to the length it has already, and I place behind another row of tubes
similar to those I have herein-before described, being of the exact length of
the elongated part of the second row. . When this second layer is constructed,
the last row of tubes, prepared as herein-before described, is elongated of twelve
feet, in order to form by that elongation alone the sides of the compartments or
casings of the third layer from distance to distance. These compartments are
separated by a space being equal in width to the diameter of one of the tubes
which is not elongated at the place where it is set; I therefore obtain by that
mode of construction an empty space which offers an open and free passage to

page_text: the sea on that part of the work immediately under the level of the water. The
remaining part of the work is constructed, as herein-before described, by
means of tubes set horizontally and imbedded in the masonry work. When I
construct a simple wall for quays, as represented by Figure 9, I make use of
one row of tubes prepared as herein-before described, but I place behind the
aforesaid row of tubes a mass of rough stones in order to afford a width to the
foundation sufficient to construct the upper works. The mode of constructing
the foundations of light houses or any other work in open sea on a bottom
of moving sands 'differs from that herein-before described, though it is
based on similar principles. Instead of using pipes for the foundations I
employ a kind of vertical coving by means of which I form a well, which,
on account of its own weight sinks down by itself as soon as the sand is
dug out of the interior until it meets with a sound ground. These covings
represented by the letters A, A, Figures 10, 11, and 12, are constructed
with sheets of iron a, b, c, d, e, and f, Figure 10, they are bent into the
form of a segment of a circle and united together by bands of iron i, k, and j, h.
These sheets of iron are provided on one side with jutting out parts b, c,
and e, f, forming a cavity into which the covings or archwise parts are
jointed one with the other, so that when they are united altogether (the last
one forming the key of the vault) they cannot be put out of the position they
have taken. When I have thus prepared the covings, I fill up with concrete
the empty spaces which exist between the two concentric cylinders formed by
the union of the sheets of iron, a, b, c, on one side, and those d, e, f, of the
other, that empty space being provided at the lower extremity with a bottom
g, h, c, k. By the mode of construction herein-before described I obtain a
piece of masonry work, which is internally hollow, forming one entire and
single picce. To sink it at the same time that the ground is dug, I put a
suitable dredging machine to work in its interior, which operates until this
artificial well has found a firm and solid bottom. When the herein-before
described operation is finished, I fill up with beton or concrete the empty
spaces produced by the excavation of the sand. I build by these means a
foundation, forming a solid block or single piece of masonry, on which I erect
the tower of the lighthouse by constructing it hollow or solid according to
circumstances. It is very easily understood that in my new mode of building,
sheets of iron, though very useful and important, are but secondary agents.
But before they are destroyed and worn out by oxidation, the concrete covered
by them has had time to be sufficiently solidified, and will last for over without
requiring any more covering.

page_text: The concrete and sheets of iron combined as I have herein-before described
can be applied with advantage for the production of conduct pipes for water,
gas, fluids, &c., and can be constructed with much more economy and dura-
bility than when made of cast-iron, or of any other material whatever.
Figures 13, 14, and 15, represent the several modes of constructing pipes,
which must naturally differ according to their several diameters. If I have
to construct tubes with large sections, I produce them by the means herein-
before described, following at the same time the directions exhibited by the
Figures 13, 14, and 15. A is the casting of the concrete; B is the sheet of
iron cylinder, serving as a mould to the conduct pipe; C, layer of rough
stones, on which the conduct pipe is set; H, prop, serving to preserve the
shape of the tube B, which otherwise might be impaired by the pression
caused by the weight of the concrete. When the conduct pipe is to be of very
large diameter, a system of a moveable scafolding serving to set the concrete
around the sheet-iron tube, it is beaten down and strongly supported by
suitable props. If I have to produce tubes having only from eight to ten
inches in diameter, I construct them in a convenient place in order to have a
sufficient quantity of them always at command, as is shown by the Figures 20,
21, and 22. The letters of the Figures herein-before described represent
similar parts in the Figures 20, 21, and 22. D is the part of the mould
serving for the construction of the pipes; E, the moveable part of the mould,
which is joined to the other by means of suitable iron pins; F is a cylinder
serving to press the concrete in the mould; G is the cylinder into which is set
the piston of the pressing cylinder F; Nos. 1 and 3 tubes serving to
introduce the steam into the cylinder G, above the piston of the pressing
cylinder F; Nos. 3 and 4 egress pipes for the escape of the steam. The
sheet iron tube B being placed in the moulds, I pour the concrete intó
the empty space existing between them, which is equal to the thickness to
be given to the conduct pipe. When that empty space is filled up with
concrete to a certain elevation, I open the top of the pipe No. 3, and I
introduce steam into the cylinder G; this agent, acting on the piston of the
cylinder F, presses down strongly the concrete confined in the mould. I
afterwards open the top of pipe No. 2, which, by giving egress to the steam,
allows the piston of the pressing cylinder F to rise to its proper place; I pour
some more concrete into the mould, and I operate as herein-before stated,
continuing thus the operation till the vacant space be entirely fitted up with
concrete; and when the artificial cylinder is consolidated and cold, I take it
out of the mould in a perfect state.

page_text: !
I must observe that the sheet iron tubes, which serve as moulds to the above
described artificial stone cylinders, have to a certain extent a conical shape;
and in order to facilitate their joining, it suffices to fill up the vacant space
which then exists at each extremity with the same substance with which they
are constructed. For that purpose I take care not to cover the metallic tubes
with concrete on all their length, and leave the metal uncovered about two to
three inches in length in each of its extremities.
The connecting pipes, either for gas, water, or other liquids or fluids aro
made on the main conduct pipes, constructed as herein-before described; by
taking off a part of the concrete coating, I hollow the sheet-iron cylinder, and
I join the connecting tube, which I fix with concrete, as I have exhibited in
Figures 16, 17, 18, and 19.
I construct also, in operating in the manner herein-before described, artificial
.rails which could replace with great advantage those of cast-iron; likewise in
operating as herein-before stated, I can produce flags, curbs for pavement, and
a number of other articles too long to enumerate.
The same Invention is equally well applicable for the construction of bridges,
roads, tunnels, and private and public buildings, for the banking of rivers, by
using for these kinds of works herein-before described, double tubes as
represented in Figures 4 and 5. The same tubes can also serve to raise the
foundations of works which are to be erected in swamps, or other similar
positions presenting little safety for erecting buildings when following the usual
mode of laying foundations.
And having now fully described my Invention, and the manner in which
.the same is to be performed, I wish it to be understood that I do not confine
myself to the precise details I have herein-before spoken of, nor to the exact
modi operandi herein-before described, provided the general features be
similar to what I have laid down; nor do I claim the apparatus, ma-
chinery, or materials employed, except for carrying out my said Inventions;
but what I claim as new and intended to be protected by the said Letters
Patent is,―
Firstly, the production of tubes, pipes, flags, curbs for pavement and tram-
roads by inserting concrete or beton between two surfaces of sheet iron, as
.herein-before described in reference to the Drawing.
Secondly, the application of concrete, combined with a double surface, to
the construction of viaducts, breakwaters, piers, lighthouses, walls of quays,
bridges, and other similar works on seas and rivers, herein-before described,
in reference to the Drawing.

page_text: Thirdly, the mode of setting together the several component parts and their
pplications, as herein-before described in reference to the Drawing.
In witness whereof, I, the said Louis Prosper Nicholas Duval Pirou,
have hereunto set my hand and seal, this Thirteenth day of October,
in the year of our Lord One thousand eight hundred and forty-nine.
L. P. N. DUVAL (L.S.) PIROU.
Taken acknowledged by Louis Prosper
Nicholas Duval Pirou (party hereto) at
Paris, in the Republic of France, this
Thirteenth day of October 1849, before me,
This is the Specification in the affidavit of William Armand Gilbee,
sworn the 16th day of October 1849, before me,
RICH T. KINDERSLEY.
William Armand Gilbee, of 4 South Street, Finsbury, in the County of
Middlesex, Gentleman, maketh oath and saith, that he is acquainted with the
manner and character of the handwriting of Thomas Pickford, Her Britanic
Majesty's Consul of Paris, in the Kingdom of France: And this deponent
further saith, that the signature "Thomas Pickford," set, subscribed, or
written in the margin of the Specification hereunto annexed, marked A, and
dated the Thirteenth day of October instant, and purporting to be executed
by Louis Prosper Nicholas Duval Pirou, of Paris, whereby it is stated that
the Specification was acknowledged by him, the said Louis Prosper Nicholas
Duval Pirou, before the said Thomas Pickford, on the said 13th day of
October, at Paris aforesaid, is of the proper handwriting of the said Thomas
Dial-fl
Sworn at my Chambers, Southampton Buildings,
in the County of Middlesex, this 16th day of
W. A. GILBEE.

page_text: AND BE IT REMEMBERED, that on the oath of William Armand
Gilbec, the Specification aforesaid was enrolled word for word as above
written. And also the Specification aforesaid was stamped according to the
tenor of the Statute made for that purpose.
Enrolled the Sixteenth day of October, in the year of our Lord One
Light undead and fantermine