CERTAIN IMPROVEMENTS IN THE CON- STRUCTION OF PIERS, EMBANKMENTS, BREAKWATERS, AND OTHER SIMILAR STRUCTURES
Year: 1843

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, LAWRENCE
HOLKER POTTS, of Greenwich, in the County of Kent, Doctor of Medicine,
send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Fifth day of December, in the seventh year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said Lawrence
Holker Potts, my exors, adñors, and assigns, Her especial licence, full power,
sole privilege and authority, that I, the said Lawrence Holker Potts, my
exors, adiñors, and assigns, and such others as I, the said Lawrence Holker
Potts, my exors, adiñors, or assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term of
years therein expressed, should and lawfully might make, use, exercise, and
vend, within that part of Her Majesty's United Kingdom of Great Britain
and Ireland called England, Her Dominion of Wales, and the Town of
Berwick-upon-Tweed, my Invention of "CERTAIN IMPROVEMENTS IN THE CON-
STRUCTION OF PIERS, EMBANKMENTS, BREAKWATERS, AND OTHER SIMILAR STRUCTURES;"
in which said Letters Patent there is contained a proviso, that I, the said
Lawrence Holker Potts, shall cause a particular description of the nature
of my said Invention, and in what manner the same is to be performed, under
my hand and seal, to be inrolled in Her 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 there-
unto had, will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Lawrence Holker Potts, 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 Specification thereof, reference being
had to the Drawings hereunto annexed, that is to say :-
The nature of the said Invention consists, first, in employing, in the con-
struction of piers, embankments, breakwaters, and other similar structures,
hollow piles of iron or other suitable material, and of a circular or other
convenient form, such hollow piles being sunk by withdrawing from their
interior, by suction, the sand or other matter occupying the space into which
the pile is to be sunk, and which piles, after having been so sunk by suction
instead of ramming, may, if necessary, be filled either wholly or partially with
concrete or other suitable materials. Secondly, in employing hollow piles sunk
as aforesaid in connection with skeleton and tank-like cases to form such
structures as aforesaid. Thirdly, in injecting or forcing by bydraulic or other
pressure, down, through, around, or amongst the lower ends or feet of the said
hollow piles (after they have been fixed in their places) such chemical solutions,
pastes, or mixtures, as according to the nature of the ground penetrated,
whether the same consists of alluvial earth, or peat, or sand, or clay, or chalk,
or any other matter or combination of matters, may combine with, agglutinate,
support, or solidify the materials immediately surrounding the feet of the piles;
and, fourthly, in the use and application, in the constructions aforesaid, of
cements in the state of dry powder, the said dry powder being constituted so
as to solidify under water and form, either alone or in combination with other
materials, artificial rock at the spot at which it is applied. And the manner,
in which the several parts of the said Invention are performed is as follows:-
Figure 1 of the Drawings hereunto annexed represents the sinking, by
pumping instead of by ramming, of one of a series of hollow piles into a bank
of sand covered with water. The pile A, which is open at the bottom instead
of being closed, as in the case of a pile to be rammed, is first placed on end
over the spot where it is to be fixed, and being allowed to drop through the
water into the sand, the entrance of any air at the bottom is thereby effectually
excluded. The top of the pile has then an air-tight cap B fitted upon it, and
this cap is connected, by means of a flexible tube or hose C, to a receiver D.
E is a three-barrelled air pump, which is connected by another flexible hose to
the receiver D on the opposite side. The air pumps being now set to work,
as the air within the receiver and the hollow pile and the intermediate con-
necting tube becomes exhausted or attenuated, a semi-liquid mixture of sand
and water flows up into the receiver, and as often as the receiver is filled, the

page_text: contents are drawn off through a trap valve F at the bottom. As the sand is
thus pumped up, the pile descends by its own weight and by the pressure of
the atmosphere to occupy the place of the solid materials removed. The air
pump is made three-barrelled, in order that a continuous flow of the semi-
liquid mixture may be kept up, for in proportion to the amount and continuity
of the power applied will be the rapidity with which the sinking of the pile is
effected. In some places, such as quicksand and mud banks, the solid materials
to be removed will be so loose, and the natural access of water so constant and
abundant, that the pumping may be continued without intermission till the
pipe has been sunk its entire length or to any extent desired, but in other
places it will be necessary from time to time to stir up by suitable instruments
the soil of the area included within the pile, and also to pour additional supplies
of water down the pipe; for this purpose there is a stuffing box G in the top
of the cap, by means of which cap the instruments and water may be intro-
duced. This cap is kept tight in its seat by the pressure of the atmosphere
with the help of an interposed gasket or leather washer, or by any other suit-
able means. Fig. 1 a is an enlarged section of the stuffing box. To accelerate
the descent of the pile, weights H, H may be temporarily placed upon or
attached to the top of the cap. For the better exclusion of sand or water
from passing between the piles, a length of gasket or other coarse fabric may
be passed down the side of each pile at Figures 27 and 28. Should any
stratum be encountered of too hard a nature to be penetrated by the above
means, then boring tools, such as are used in the sinking of artesian wells, may
be had recourse to to break it up, and for the sake of greater facility in work-
ing these tools, the cap may be removed altogether during the operation. If
one length of pile is not sufficient, two or more lengths may be made use of, by
screwing or otherwise joining them endwise together. But that the descent of
the piles may not be obstructed by anything protruding externally from them,
the flanges, where such means of junction are employed, should be cast on the
inside of the piles, as represented in Figures 2, 3, and 4 of the Drawings
hereunto annexed. Very excellent joinings may also be made by casting the
piles at one end with a male taper screw, and at the other with a female taper
screw to correspond, as represented in Figure 5, screwing the one into the
other. Should the lateral friction of the soil on the exterior of a pile be too
great to allow it to descend far enough, others of lesser dimensions may be
inserted within it. The arrangements before described are well adapted for
sinking piles of moderate diameter or section, and where the flow of water, or
sand, or other materials from the exterior to the interior of the pile is free.
But when the sand or other material has such a consistency that the con-

page_text: nection between the interior and exterior is not free, or the water has
not an uninterrupted passage into the hollow pile, or when from other
causes it may be expedient to use piles of such magnitude that the exhaus-
tion of them would be a matter of difficulty, the process of excavation
may be, nevertheless, effected on precisely the same principle, by con-
necting a moveable tube of small size (which I call an elephant or operating
trunk) to the exhausting apparatus, and passing it down through the then
open pile or case, as represented in Figure 6ª and 6b of the Drawings
hereunto annexed, but in this case the tube need not have any stuffing
box at top, as the stirring tools can be introduced, when required, through
the open head of the pile or case. When extraordinary expedition is calle
for, there may be two or more such operating trunks employed at the same
time, each trunk being connected by a separate flexible hose with the exhaust-
ing apparatus. And if the interior of the pile is large enough, persons may be
sent down into it to guide the flexible shifting tube or tubes to all parts of the
included area. In some cases it will be proper to provide the workmen with a
tub or cobble, as represented in Figure 6b, to afford them a sure footing, and
also to keep them afloat in the event of any rush upwards, or "blowing up,"
as it is termed, of the sand or soil. Figure 7 represents both the preceding
plans applied in combination at a distance from the shore, the exhausting
apparatus and workmen being floated to the spot in a barge or other vessel.
A is the smaller tubular pile, which is, by the process of exhaustion, to be itself
permanently sunk into the sand; A2, the large open pile, with the small ope-
rating trunk (I) applied inside of it, and a workman (K) to guide it. When
the depth of a large open-topped pile, or series of piles exceeds thirty feet, the
receiver D must be placed within that distance of the water, sand, or other
matter to be raised; and the contents of the receiver may be raised to the
surface by similar means to those already described, or by any of the means
ordinarily employed to raise the materials in sinking pipes or shafts for wells.
In some cases, after the pile or series of piles has been sunk to the desired
depth, it may be wholly or partially filled up with concrete, grouting, cement,
or some other hard material or combination of materials; but, before doing
so, should the soil at the bottom be of a yielding description, it may be proper
to consolidate and strengthen it above and about the foot of the pile, by pouring
or forcing down through the hollow pile, or by means of a small tube carried down
within the hollow pile, such chemical solutions or pastes as the nature of the
soil and previous experiment may point out to be best adapted for the purpose.
For example, by analysing samples of the soil obtained from different depths,
it can be ascertained what its component parts are, and, according as silicious

page_text: or calcareous, or other materials predominate, it will be seen what class of
chemical substances, simple or compound, will be best calculated to combine
with and solidify them. And, in like manner, it may be also ascertained, by
preliminary trials on a small scale, which of various substances, simple or com-
pound, will effect the desired induration the most speedily and effectually. In
constructing an embankment, or a breakwater, or any other similar structure,
the face of it may be formed of any number of such piles as before described,
either arranged in a single row close to one another, or in two or more rows,
the piles of cach row being placed opposite the joinings of the row in front, as
represented in the plan and elevation, Figures 8 and 9. In either case the
piles may be backed or filled up by concrete or fragments of rock, united by
cement, or some other solid and durable material or materials. Where the bottom
soil is of such a description as to make it expedient to indurate it by means of
hydraulic or other lime, or by chemical pastes, or solutions sent down through
the hollow piles, as already described, the piles may be each alternately short and
long, as represented in Figure 10, because, thereby, the bulbous sort of masses
formed round the feet of the shorter piles will afford a useful support to the
longer piles adjacent. Where the resistance which it is requisite to oppose to
the water is very great, there may be two ranges of hollow piles, sunk at any
distance from each other, each range consisting of one, two, or more courses,
and the space between them made good, if necessary, by grouting or otherwise.
Piers or other structures having two faces exposed to the water may be con-
structed in the same mode as that last described, and for greater security, the
opposite courses of piles may be connected together by transverse binding rods.
Or, such piers and other like structures may be formed by means of a series of
skeleton frames, such as represented in Figures 11, 12, 13, 14, and 14", placed
one above the other, having at each side circular (or other shaped) orifices,
through which the piles may be sunk, and the interior spaces being filled up
with concrete or any other solid materials. In some cases, instead of having
the piles close together, sufficient strength may be obtained by sinking piles at
intervals, only connecting them sidewise by flat plates, and crosswise by straight
or semi-diagonally-tied binding rods, as represented in Figures 15, 16, and 17,
or connecting them crosswise by binding rods only, as in Figure 17ª. In
Figure 18 an interior skeleton framing is substituted for the straight and semi-
diagonal cross rods. The sinking of the side plates into their places may be
effected by applying an exhausting operating trunk or trunks, such as has been
before described, to draw away the sand or other soil from under it as it
descends, in the manner represented in Figure 19. And the joinings of the
piles with the side plates may be effected in any of the modes represented in

page_text: Figures 18, 19, 20, 21, and 22. Where the saving of iron may be an object,
another mode of constructing piers and other two-faced structures, represented
in Figures 23 and 24, may be advantageously adopted. P is an open iron
case or tank, of an oblong form and of the height of the intended pier or other
structure, the inner side of which is connected to the others by bolts e, e, f,f,
and
9, 9, in the manner shewn in the Drawings, and detachable from them by
undoing these connections. Two ranges of such cases or tanks being dropped
at a distance from each other, regulated by the width desired to be given to
the pier or other like structure, the inner or detachable sides of the opposite
ranges are connected by cross rods f, f, and other rods g, g, are passed through
the outer sides and screwed on to the rods f, f. (washers being interposed
between the shoulders of the rods 9, 9, and the outer plates where they come
into contact) whereby the whole frame-work is securely fixed together. The
space between the two ranges of cases or tanks is then filled up with loose
stones, blocks of chalk, or other solid materials, and the whole bound together
by any suitable cement, applied in a dry state or otherwise. After the sort of
artificial rock thus formed has become sufficiently hardened and consolidated,
the rods g, g, are unscrewed from the rods f, f, and the bolts e, e, also with-
drawn, when the three connected sides of the cases may be removed, and the
inner sides only left in their places to serve as facings to the pier or other
structure; or if the newly-formed rock be sufficiently firm and solid, the whole
of the iron-work, excepting the tie-rods and braces, may be removed. Cases
will occur when, before a pier, embankment, or other similar structure can be
formed by any of the methods before described, the ground must be cleared of
accidental obstructions, such as wrecks of vessels. In accomplishing this, great
advantage may be derived from making use of my elephant or operating trunk,
to free the wreck or other obstructions from the sand or mud in which it is
imbedded, when it may be raised with comparative ease. A helmeted diver
might apply the pipe in its proper place, while the apparatus would be worked
from above. Where a shaft is required to be sunk through a rocky or other
hard bottom covered with water, large hollow piles of ten feet in diameter and
upwards, and cast in two or more segments, as well vertically as horizontally,
may be let down through the water upon the solid bottom, and upheld there
by means of large stones dropped around the pile and united together by any
suitable cement (the sand or mud having been previously cleared away by the
operating trunk). Figure 26 is a plan, and Figure 27 an elevation, of a structure
of this description.
The last part of my Invention consists in applying cement in the state
of dry powder to form structures and foundations under water, the cement

page_text: mixing with the water and forming a solid mass.
The cement employed may
be any of those known as hydraulic cements, and may be used either
alone or intermixed with sand, stones, or shingle. The dry cement may be
delivered at the spot where it is required through a continuous tube from
the surface of the water; or vessels or canisters, for the delivery of such cement
in a powdery state, under water may be either of the form represented in
Figures 29 and 30, having a single trap door C at bottom, which is opened or
closed by means of a rod or line D, and two hooks at top, by which it is slung
from a crane or other suitable support; or it may be constructed in the manner
represented in Figure 31 (elevation), 32 (top plan), and 33 (bottom plan, that
is to say, divided into four compartments t, u, v, w, with separate trap doors at
bottom, one to each compartment,) which may be opened in succession by
turning round a central rod æ, which terminates in a button y of the form of a
circle, having one quarter segment cut away.
And having now described the nature of the said Invention, and in what
manner the same is to be performed, I declare that what I claim as my
Invention is,
First, the employment, in the construction of piers, embankments, break-
waters, and other similar structures, of hollow piles made of any suitable form
and materials, and the sinking of such piles into their places by the abstraction
of the natural foundation into which they are sunk, by suction, as herein-before
described. And I hereby disclaim, as of my Invention, the filling hollow piles,
or the combining hollow piles into the above-mentioned constructions, except
when such piles have been sunk in the manner aforesaid, instead of being
rammed or driven.
Secondly, I claim the employment, in manner aforesaid, of hollow piles,
sunk as aforesaid by suction instead of ramming or driving, in connection with
skeleton frames and tank-like cases, to form piers, embankments, breakwaters,
and other similar structures.
Thirdly, I claim the employment, in manner aforesaid, of chemical sub-
stances, simple or compound, to agglutinate, indurate, and consolidate or
support the soil in which such hollow piles, sunk as aforesaid by suction, and
not by ramming or driving, are inserted.
And, lastly, I claim the employment, in the construction of piers, embank-
ments, and other similar structures formed under water, of dry cement, in the
manner herein-before specified.
In witness whereof, I, the said Lawrence Holker Potts, have hereunto
set my hand and seal, this Fifth day of June, One thousand eight
hundred and forty-four
L.. II. (L.S.) POTTS.

page_text: AND BE IT REMEMBERED, that on the Fifth day of June, in the year
of our Lord 1844, the aforesaid Lawrence Holker Potts came before our
said Lady the Queen in Her Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained and specified, in form
above written. And also the Specification aforesaid was stamped according
to the tenor of the Statute made for that purpose.
Enrolled the Fifth day of June, in the year of our Lord One thousand
eight hundred and forty-four.