IMPROVEMENTS IN COFFERDAMS, AND IN APPARATUS TO BE USED THEREIN, AND IN SINKING CYLINDERS AND TANKS FOR MAKING FOUNDATIONS UNDER WATER
Year: 1864

page_text: LETTERS PATENT to John Shaw, of No. 22, West Smithfield, London, in
the County of Middlesex, Engineer, for the Invention of "IMPROVEMENTS
IN COFFERDAMS, AND IN APPARATUS TO BE USED THEREIN, AND IN SINKING
CYLINDERS AND TANKS FOR MAKING FOUNDATIONS UNDER WATER"
Sealed the 19th April 1865, and dated the 20th October 1864.
PROVISIONAL SPECIFICATION left by the said John Shaw at h
Office of the Commissioners of Patents, with his Petition, on the 20th
October 1864.
I, JOHN SHAW, of No. 22, West Smithfield, London, in the County of
Middlesex, Engineer, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN. COFFERDAMS, AND IN APPARATUS TO BE USED THEREIN, AND IN
SINKING CYLINDERS AND TANKS POR MAKING FOUNDATIONS UNDER WATER," to be as
follows:-
The object of my Invention is to facilitate the operations in forming coffer
dams, and in sinking caissons, cylinders, tanks, and piers, for making
foundations under water; also to economise labor in raising or discharging:
the soil or materials excavated, and at the same time dispense with the use of
pumps for drawing off the water.
The nature of my Invention consists in forming iron caissons with curved
sides and flat ends with flanges on the top and bottom of all the upper
caissons and flanges on the top only of all the bottom caissons. Projections
are made vertically, and at right angles with the ends of the caissons to fit

page_text: into each other, and form a puddle box when put together, and the caissons
are built end to end, and raised in tiers with water and air-tight joints bolted
together to the length and height required.
Apparatus in the form of a condenser or chamber is fixed on the top of the
caisson, cylinder, or tank required to be sunk, and is made to receive air
through flexible tubes by means of an air pump worked by a steam engine
to a pressure sufficient to force out the water from the bottom of the caisson,
cylinder, or tank, and thereby enable worknien to sink the same down to a
solid foundation without the aid of pumps. The condenser or chamber is
made to overhang the caisson on each side, and when made-shorter than the
length of the caisson the part not covered by the condenser or chamber is
covered by an extension of the bottom plate of the condenser at each end, and
the whole is fitted and bolted on the top of the caisson with an air-tight
joint, an opening being left in the centre of the bottom of the condenser, and
a man-hole formed on the top.
.
".
A similar arrangement is made for sinking piers and cylinders, the condenser
being made one way to hang over the piers or cylinders to effect the discharge
of the soil through the hopper.
The condenser or chamber is made of sufficient capacity for men to work
in, and is fitted inside with a hopper for discharging the soil or materials
excavated, and a small cistern, the hopper being placed on the part of the
condenser that, overhangs the caisson, and a windlass is fixed.
over the opening
left in the centre of the condenser for raising the soil or materials from the
caisson. The hopper is fitted with two valves, one at the top and the other.
at the bottom, and is made to receive the materials excavated, which are tipped
into the top as they are raised by the windlass from the bottom of the caisson.
The upper valve is left open to receive the materials, and the lower one kept
shut; but when the hopper is discharged the action of the valves is reversed,
the top being closed and the lower one opened. When the lower valve is
opened the materials drop out, and are discharged through a trough when
required into a barge beneath. The small cistern is fixed near the hopper
and connected thereto by a short pipe fitted with a stop-cock, and receives the
water drained from the materials in the hopper. When the materials are dis-
charged and the bottom valve shut, the stop-cock is opened to let out the water
from the cistern into the hopper until the pressure becomes equal to the air in
the condenser, so as to allow the upper valve to be easily opened. On again
filling the hopper with the materials, the water is again forced into the cistern
and the cock closed before the bottom valve is re-opened. A pipe is attached
to the hopper and descends down the caisson, in order to blow the water out of

page_text: the caisson when required, the top valve of the hopper being closed and the
lower one opened for the discharge of the water.
When the caisson is sunk down to a good foundation, and the bottom well
puddled, the condenser is lifted off and placed over the next caisson to be
operated upon in a similar manner, and so on with the rest in succession, the
boxes formed between the end of the caissons being filled with .puddle as they
progress.
The caissons can be extended to any length, and are returned at right angles
when a cross dam is required; projections being made on the broad side of the
caisson to receive the ends of the adjoining caisson, and form the box to
receive the puddle.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Shaw in the Great Seal Patent Office on the 20th
April 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
SHAW, of No. 22, West Smithfield, London, in the County of Middlesex,
Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twentieth day of October, in the year of our Lord
One thousand eight hundred and sixty-four, in the twenty-eighth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said John Shaw, Her special licence that. I, the said John Shaw,
my executors, administrators, and assigns, or such others as I, the said
John Shaw, 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 "IMPROVEMENTS IN.
COFFERDAMS, AND IN APPARATUS TO BE USED THEREIN, AND IN SINKING CYLINDERS
AND TANKS FOR MAKING FOUNDATIONS UNDER WATER," upon the condition.
(amongst others) that I, the said John.Shaw, 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 John Shaw, do hereby declare the
nature of my said Invention, and in what manner: the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the accompanying Sheet of. Drawing
forming part of this my Specification, and to the figures and letters of reference
placed thereon. Similar letters denoting similar parts in each of the Figures
respectively.
Figure I being a longitudinal section; Figure 2, a top plan view; Figure 3,
a transverse section-; -and Figure 4, a sectional plan of my improved caissons
or coffer. dams, and the apparatus to be used therein.
A indicating a lower caisson, and A¹, A", halves of adjoining caissons; B,
an upper caisson, and B, B", halves of adjoining-ones; b, flanges-to.caissons.;
m, curved sides to same; n, flat ends; C, a condensing chamber; c, bottom
of same; c, flanges; k, (Figure 3) top of condenser C; 1, man-hole; .D, a
hopper; d, upper valve to same, covering opening d¹; e, throttle valve covering
hole e¹; h, crank handle for working valve e; E, a cistern with 'union pipe F,
leading to hopper, and f, stop-cock on union pipe; G, puddle boxes formed by
the vertical flanges g at the end of the caissons; II, extension of bottom plate
of condensing chamber covering ends of caisson; 1, an open working space at
bottom of C; and K, pipe for introduction of air to condenser C.
I form my.coffer dams or iron caissons with curved sides (m) and flat
ends (n); the upper caissons having flanges (6)" at top and bottom, and the
lower caissons flanges (b) at the top only.
My improved caissons have also vertical flanges (9) projecting at right angles
from their flat ends (n), which flanges. when the caissons are brought together
fit into each other and form puddle boxes (G)...)
: .
.
In making a foundation I place these caisons end to end, raising them in
tiers to the length and height required, the, water and air-tight joints being
made by bolting the flanges (6) together with screw bolts and nuts. I sink
them in the following manner :-I bolt on to the top of a caisson (making. an
air-tight joint), a compartment which I term the condenser (C), and by means
of an air pump worked by a steam engine, I introduce air into this condenser
through flexible tubes by the air pipe (K) and with sufficient pressure to force
out the water from the bottom of the caisson (as it descends, until it reaches
the bottom) thereby enabling the workmen to sink it down to a solid founda-
tion without the aid of pumps. Men working in the condenser (C) raise the
excavated soil or material through an opening (1) left at the bottom of the
condenser, using a windlass or other contrivance suitable for such purpose,
and tipping the soil as it is raised into a hopper (D) place inside the con-

page_text: זי
denser, and then by opening and closing.the: top and bottom valves (d, e,) in
the manner. herein-after described, the soil or material in the hopper is finally
discharged into a barge or other receptacle brought beneath the hopper, or
which may be.reached by a trough leading from it.
When the caisson is sunk to a good foundation, and the bottom. .well
puddled, the condenser is removed from.it, placed on the next caisson, the
same:operation repeated, and so on successively; the boxes (G) formed between
the caissons by the vertical flanges (9) being filled. .with puddle as the work
progresses.
The caissons can be extended to any length, and be returned at right angles
when.a.cross dam is required, projections being made on the broad side of the
caisson to: receive, the ends of the adjoining caisson, and form the box to
receive. the puddle::
21
I will now describe the, condenser, and the apparatus contained, within it.
The size of the condenser (which like the caisson above described may be
made of iron or any suitable metal or material,) will will vary according to
requirement, the top of each of its sides is.flanged (c), it has a man-hole (7)
in its top plate (k), an opening. (I), at its bottom (c) through which the
excavated material is raised as already: described, and an air pipe: (K). It is
made so as to overhang each side of the caisson upon which it is placed (as
shewn Figure 3); and, should it be shorter than the length of the caisson its
bottom plate may be extended so as to cover the top of the caisson as indicated
by the letter H, Figures 1 and 2 of the Drawing. The condenser is fitted
interiorily with a hopper (D), by which the soil or material. excavated is
discharged. as above, stated, and which is always placed on that part of the
condenser which is to overhang the caisson when fitted to it. This hopper is
furnished with valves (d, e,) at top and bottom. When the excavated
materials are tipped into the hopper, the upper valve (d) is open, and the
lower one (e) shut, and when the said excavated materials are to be discharged
from the hopper, the top valve (d) is closed and the lower one (e) opened by
means of its crank (h). The condenser also contains a cistern (E) in con-
nection with the hopper (D) by a union pipe (F), with stop-cock (f); this
cistern receives the water drained from the materials tipped into the hopper,
and when the contents of the hopper have been discharged, and the bottom
valve (e) re-closed, the stop-cock (f) is opened, and the water from the
cistern let into the hopper until the pressure becomes equal to that of the air
in the condenser, when the upper valve may be easily opened. The hopper
being re-filled, the water is again forced into the cistern, the cock (f) closed
before the button valve (e) is opened to discharge the soil, and so on con-

page_text: tinuously... Should any considerable quantity of water penetrate into the
caisson after it has entered the soil, it may be forced out by leading a pipe
from the hopper to near the bottom of the caisson, then hermetically closing
the condenser, force air into it through the air pipe (K), and the water will
be:compelled to rise into the hopper discharging itself by the lower valve (e),..
which is left open, the top valve (d) being first carefully closed; or the pipe
may pass out of the side of the condenser instead of through the hopper, and
have a cock on the exterior to shut when the water is blown down to the
bottom.
I would here observe; that although I have described the working of the
condenser only as applied to a caisson. constructed according to my Invention,
my improved apparatus may nevertheless be used to sink cylinders, piers,
tanks, and caissons otherwise constructed (that side of the condenser-on-which
the hopper is placed being always made to overhang such pier, cylinder, or
tank), and that my improvements may not only be used for forming founda-.
tions under water, but also in mining operations, for passing through quicksands
and wet places; further, that I do not confine myself to the precise details of
construction herein given or illustrated on the annexed Sheet of Drawing, as
such may be modified without departure from the principle of my improve-
ments, nor do I limit myself to any precise dimensions, as. such may and
indeed must be varied to suit the circumstances of particular cases.
In witness whereof, I, the said John Shaw, have hereunto set my hand
and seal, this Eighteenth day of April, in the year of our Lord One
thousand eight hundred and sixty-five.