IMPROVEMENTS IN THE CONSTRUCTION OP PIERS AND HARBOURS
Year: 1846

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, PETER
BORRIE, of the Crescent, Minories, in the City of London, Engineer, 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 Twenty-first day of
December, One thousand eight hundred and forty-six, in the tenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the said
Peter Borrie, my exors, adññiors, and assigns, Her especial licence, full power,
sole privilege and authority, that I, the said Peter Borrie, my exors, adñiors,
and assigns, or such others as I, the said Peter Borrie, my exors, adñors, 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, my Invention of "IMPROVEMENTS IN THE CONSTRUCTION
OP PIERS AND HARBOURS;" in which said Letters Patent is contained a proviso
that I, the said Peter Borrie, shall 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 fully and at large

page_text: NOW KNOW YE, that in compliance of the said proviso, I, the said
Peter Borrie, do hereby declare the nature of my Invention, and the manner
in which the same is to be performed, are fully described and ascertained in
and by the following statement thereof, reference being had to the Drawings
hereunto annexed, and to the figures and letters marked thereon, that is to
say:―
My Invention consists,. firstly, of improvements in the construction of low-
water piers, three different arrangements of which are shewn in the Drawings
in Sheets Nos. 1, 2, and 3. It will be seen from an inspection of these
Drawings that piers as thus constructed consist of three parts, vidilecit, a
fixed pier or jetty, a floating pier or barge, which is kept in its place longi-
tudinally and laterally by a pier or buttress at each end, but which is at
liberty to rise and fall with the tide; and a bridge strongly hinged on the
end of the fixed pier, and resting on the floating pier so as to form & com-
munication between the two at any state of the tide.
Sheet No. 1. In this Sheet is represented a method of constructing my
improved pier for light traffic, such as passengers, carriages, and luggage or
light goods, and in which the fixed pier or jetty and the bridge are chiefly
formed of timber. In the various Figures on this Sheet the same letters are
used to indicate similar parts.
Figure 1 is an elevation of the pier; Figure 2 is a plan of same; Figure 3
is an elevation of the bridge as connected to the fixed and floating piers, on a
larger scale; Figure 4 is a plan of the same; Figure 5 is a front elevation
of one of the piers or buttresses for mooring the floating pier; and Figure 6
is a side elevation of one of these buttresses. A, A, A, are frames formed of
piles strongly braced and connected together, so as to form distinct piers, with
clear waterways between them, on which piers the roadway of the fixed pier
or jetty rests. The outer pier A¹ is strengthened with struts fixed to pile
foundations, in order to enable it to withstand the action of the bridge which
is hinged near the top of it. On the top of these piers longitudinal beams or
sleepers B, B, B, are laid, which sleepers are connected together with cross
pieces and diagonals, as shewn in the Drawing. Between the piers these
sleepers are trussed with iron tension bars passing under two cross beams
fixed under them, the tension bars going through beams fixed above the
sleepers on the top of each pier, and having their ends screwed with nuts
screwed upon these beams. The roadway C, C, C, rests upon and is fixed to
the sleepers. It is formed by joists c, c, c, laid crossways on the top of them,
to which joists the planking forming the upper part of the roadway is securely
fastened. Now, although the fixed pier or jetty is represented in this Drawing

page_text: as being curved at its inner end, this may be by no meaus necessary, as it
will altogether depend upon the nature of the situation in which the pier is to.
be erected, and of the position where it is considered desirable that the ter-
minus should be situated. The floating pier D, D, is moored at such a
distance from the end of the fixed pier that there may be sufficient depth of
water at the lowest state of the tide to float any vessel to which the pier is
intended to give accommadation, and at the same time to allow the bridge
which connects them to be of such a length that at low water the inclination
of the roadway may be easy for carriages or any other traffic for which the
pier is designed. In the Drawing this floating pier or barge is shewn as
being built of iron; but I do not confine myself to constructing it of this
material, as it may be formed of timber or other substances. In the Drawing
it will be observed that the bottom of the barge is so formed that when
floating with the deck on a level athwartships to have more displacement on
the side next the bridge than on the other side, and this is done in order to
enable it to support the weight of the bridge which rests upon it. This bargo
is is also divided into three compartments by two watertight bulkheads, which
add to its safety and stiffness. The floating pier is moored or kept in its
place by piers or buttresses F, F, at each end, formed of piles strongly framed
and braced together, as shewn in the Drawing. Fixed to each end of the
floating pier there are rollers E, E, working in strong iron frames, which
rollers bear against the buttresses, and allow the floating pier to rise and fall
with the tide, but prevent its getting out of its place longitudinally or laterally.
The floating pier is provided with proper gangways, stairs, &c. for the accom-
modation of the craft for which the pier nay be designed. It will be seen
not placed at right angles to the
in this Drawing that the floating pier is
jetty and bridge; but this altogether depends upon the direction of the current
at the place where the pier is situated, as the floating pier should always be
placed in such a position that its centre line will lie in the direction of the
current.
The bridge is formed of three main beams H, H, H, supporting the road-
way G, G. These beams have cast-iron sockets on each end, forming the
hinge at the fixed pier, and the bearings for the rollers at the floating pier.
They are strengthened by iron tension bars on the lower side, the beams being
slightly curved upwards, and connected to the tension bars by strong iron ties,
ns represented in the Drawing, so that the force upon the beams acts against
that
upon the tension bars, thus forming a combination of great strength and
stiffness. These beams have stringers or shelf pieces bolted on their sides for
supporting the joists of the roadway, and they are connected together by ties

page_text: and diagonals, as shewn in the Drawing, so as to form one strong piece of
framework. The joists are properly secured to the stringers, and the planking
forming the upper part of the roadway fastened to them in a similar manner
to that forming the roadway of the jetty. The hinge forming the junction
with the end of the fixed pier is formed by strong cast-iron brackets securely
bolted to this pier, on which the circular projections on the ends of the sockets
of the main beams of the bridge rest, and a strong wrought-iron bolt passes
through all, so as thoroughly to secure the end of the bridge to the fixed pier.
The sockets at the other end of the bridge are fitted with rollers, which bear
upon rails fixed in a recess on the floating pier at I, I, so that the bridge will
always accomodate itself to the position of the floating pier as the tide rises
or falls. In order to diminish the strain on the joint of the fixed pier, and
also to insure greater safety, I connect the bridge to the end of this pier by
three chains, which chains can at any time be tightened up by screws con-
necting them to the end of the fixed pier. At each side of the fixed pier and
bridge is a rail or parapet, the floating pier also having a proper rail round it,
with gangways and stairs for the accomodation of different sizes of boats or
vessels, and also timber heads or posts for mooring such vessels, and the whole
may be lighted with lamps as shewn in the Drawing. Along the whole of
the roadway of the fixed pier and bridge, and also on the deck of the floating
pier, proper scuppers are formed to run off the water.
Sheet No. 2.-In this Sheet a pier of similar construction to that described
above is represented, but adapted for heavier traffic. Like the former, the fixed
pier and bridge are chiefly constructed of timber, but the whole is so designed as
to bear the heaviest loads that generally pass over structures of this description.
In the different Figures on the Sheet the same letters refer to similar parts.
Figure 1 is a longitudinal elevation of the pier. Figure 2 is an elevation of the
floating pier. Figure 3 is a general plan of the whole. Figure 4 is an elevation
of the outer end of the fixed pier. Figure 5 is a transverse section of the fixed
pier. Figure 6 is a transverse section of the bridge. Figure 7 is a plan of
part of the under side of the fixed pier on an enlarged scale. Figure 8 is a
plan of the outer end of the bridge on an enlarged scale. Figure 9 is some
of the tension bars on an enlarged scale. Figure 10 is one of the tic bars on
an enlarged scale. Figure 11 is the saddle for the bridge on an enlarged
scale. Figure 12 is the beam and shaft for end of bridge, on an enlarged
scale. The piers a, a, a, a, of the fixed pier or jetty, are, as in the former
case, formed of piles braced and trussed together, as shewn in the transverse
section Figure 5. On the top of these piles cast-iron sockets b, b, b, b, are
fitted, having seats for the longitudinal or main beams of the roadway, and also

page_text: strong cars for the tension bars passing through cast upon them.
The outer
pier a¹ is strengthened as formerly with struts, and the sockets on the top of
it have bearings cast on them for the hinge on the end of the bridge, as
shewn in Figures 1 and 4. On the top of these piers, and fitting into the
seats upon the cast-iron sockets, longitudinal beams c, c, c, c, are fixed, which
beams are slightly bent upwards, and have tension bars below on each side,
to which they are connected by iron ties, as shewn in the Drawing. Theso
beams are connected together with transverse beams and diagonals, as shown
in Figures 3 and 7. The roadway d, d, d, d, is supported on these beams,
and is formed of wooden planking nailed to joists, similar to that formerly
described. The floating pier e, e, is here represented as formed of iron, and
is similarly shaped in the bottom, and moored in the same manner as in the
former case, having gangways, stairs, &c., for the use of vessels lying alongside.
There are also cranes f, f, erected on it for lifting any heavy articles to or
from such vessels. The interior of the floating pier is formed into three com-
partments by two watertight bulkheads, which compartments may be used
as depots for goods not requiring to be immediately shipped; and these
bulkheads will not only add to the safety of the pier in case of collision, but
will also be of great advantage in stiffening the sides. The bridge h, h, which
connects the fixed and floating piers, is constructed as before of three longi-
tudinal beams strongly trussed with iron tension bars supporting the roadway,
the whole being bound together with cross braces and diagonals, as shown in
Figures 3 and 6. The hinges of the bridge are formed by sockets or caps on
the ends of the longitudinal beams, which sockets have ears cast on them
through which the tension bars pass. The inner end rests on strong bearings
cast on the caps of the piles of the outer part of the fixed pier, and has a
strong wrought-iron bolt passing through it so as to form a joint, and it is
also connected to the end of the fixed pier by safety chains, as described in
the former case. The outer end is connected in a similar manner to a cast-
iron beam fixed on a shaft, resting on bearings attached to the floating pier,
as shewn in Figures 8 and 12. The connection as thus constructed forms a
double joint between the bridge and the floating pier, which allows it to have
both a pitching and a rolling motion without affecting the bridge. It will
be seen that this arrangement is necessary in situations where the floating
pier would be exposed to the action of the waves, or other causes which
would produce any considerable motion in it, as such motion would throw a
great strain upon the bridge were this mode of connection not adopted. As
before, the fixed pier and bridge are surmounted by a rail or parapet at each
side, and the roadway is fitted with scuppers as in the former case, and has an

page_text: iron tramway fixed on it, dividing the whole breadth into a roadway for
carriages, with a footpath for passengers on each side of it, and the whole
may be lighted with lamps, as shewn in the Drawing.
Sheet No. 8. The pier as shewn in this Sheet is principally constructed
of iron, and is adapted for traffic of the heaviest description. Like those
-formerly described, it consists of three parts, videlicet, a fixed or stationary
'part, a floating pier or barge, and a bridge connecting the fixed and floating
piers. In the different Figures on the Sheet the same letters refer to similar
⚫parts.
Figure 1 is a longitudinal elevation of the pier; Figure 2 is a general plan
of the same; Figure 3 is a transverse section of the fixed pier; Figure 4 is
'a transverse section of the bridge; Figure 5 is a transverse section of part
of the fixed pier, on an enlarged scale; Figure 6 is a longitudinal section of
the main beams at the joinings, on an enlarged scale; Figure 7 is a plan of
the beam for the end of the bridge, on an enlarged scale; and Figure 8 is a
plan of part of the lower side of the roadway, on an enlarged scale. Each
of the piers a, a, a, of the jetty or fixed part, consists of cast-iron columns
(resting upon secure foundations of stone or other material), strongly con-
nected together, as shewn in Figure 3. The columns of the outer pier are
strengthened with strongly feathered struts cast on each side of them, in order
⚫ to enable them to withstand the pull and thrust of the bridge. The main
beams b, b, b, are of cast iron of the form of section shewn in Figures 3
and 5, and are strongly secured on the top of the piers. These beams are
curved slightly upwards, and may be cast in pieces, and joined, as shewn in
Figure 6. They are strongly trussed with wrought-iron tension bars passing
below them, as shewn in the Drawing, the tension bars having eyes fixed in
the ends of the beams, the beams also being connected to the tension bars
throughout their length by strong iron ties and diagonals. It will be seen
that this will make a very strong combination, for the beam being curved
upwards, any weight coming upon it has a tendency to bring it down in the
middle, and accordingly to lengthen it; but it cannot come down without the
ties throwing a corresponding strain upon the tension bars, and these being
fixed to the end of the beam, any strain upon them tends to bend the beam
upwards, by drawing its ends together, so that the one strain acts against the
other, and the strength of the beam depends upon the strength and curvature
of the tension bars or chains upon which the beam may be said to rest.
These beams are connected together with transverse beams and diagonals of
cast iron, as shewn in Figures 2 and 8, and the ends of the beams above
the outer pier are formed into bearings for the end of the bridge resting on.

page_text: Now although I have only shewn three lines of main beams in the breadth
of this jetty, a greater number may sometimes be required where it is necessary
to have a broader roadway; and although I have shewn the piers as formed of
pillars or columns, I may sometimes vary this, as other kinds of framework
may be adopted. The roadway c, c, c, c, is supported on the main beams,
and is formed of wooden planking nailed to joists. as in the cases formerly
described, which joists are also of wood, and are securely bolted to beds or
bearings cast upon the main beams. But although the joists and covering
of the roadway are here shewn as of timber, I may. sometimes use iron joists
with wooden planking, or sometimes make both joists and covering of iron.
As in the two former cases, the floating pier or barge d, d, is here represented
as constructed of iron with a wooden deck; and in order to sustain the weight
of the bridge which rests on its bottom, is similarly formed to those already
described. The interior is divided into three compartments by two water-
tight bulkheads; but I may sometimes have more than two bulkheads in the
barge, as its safety and stiffness will be increased by having a greater number.
Also in forming a floating pier for any situation where it would be much
exposed to the force of the sea, I connect the two sides with a number of open-
ended water-tight tubes or funnels, the centre of which tubes are above the
water line, and also have a number of open-ended water-tight tubes inserted
between the bottom and the deck, so that the sea would break through such
tubes, and they would also be of great service in strengthening the vessel.
The floating pier is fitted with gangways, stairs, cranes, &c., for the accom-
modation of all classes of vessels using the pier, and is moored with buttresses
e, e, at the ends, in a similar manner to the piers already described. These
buttresses are shewn in the Drawing as formed of timber piles strongly tied
and braced together; but in some cases I make them wholly of cast-iron frame-
work, resting on stone or other substantial foundations. The bridge f, f, is
formed of three beams 9, 9, 9, supporting the roadway. These beams are.of
cast iron of a similar form of section to the main beams of the fixed pier, and
are cast in lengths, and joined in the same manner as those beams. They are
also trussed with wrought-iron bars in a similar manner to those beams, and
are strongly connected with cross beams of diagonals of cast iron, as shewn in
the plan, Figure 2. On the inner ends of these beams circular joints are cast,
which rest on the bearings on the end of the fixed pier, and a strong iron
bolt passes through the whole, forming a hinge, the end of the bridge being
further secured by safety chains, as formerly described. The other ends of
the beams are formed into bearings for rollers, which rollers bear upon a
platform h, I, formed upon two beams i, i, which beans are fixed upon a

page_text: shaft resting on bearings h, k, attached to the floating pier, as shewn in Figures
1 and 7. It will be seen that this method of supporting the end of the
bridge upon the floating pier, like that described in the last case, allows it (the
floating pier) to have both a pitching and a rolling motion, without strain-
ing the bridge. The fixed pier and bridge have, as formerly, an iron railing
at each side, and the roadway is provided with scuppers, also an iron tramway,
forming a carriageway, with a footpath at each side, and the whole is fitted
with lamps, &c., as represented.
In the foregoing descriptions of this part of my Invention I have supposed
that a certain length of jetty or fixed pier is necessary in order to obtain a
sufficient depth of water at all times of the tide; but in some cases this may
not be necessary, where the depth can be obtained within a short distance of a
wharf or sea wall, and in that case the bridge would be hinged immediately
to such wharf or sea wall. Also in some cases the difference between
high and low water may be so great that in order to diminish the inclination
of the bridge, and adapt it for general traffic even at the lowest state of the
tide, the bridge would require to be of an impracticable length, and in those
cases I make the bridge in two lengths, and employ an intermediate floating
pier, on which the outer end of the first length rests on rollers, and the inner
end of the second length is jointed to, and this intermediate floating pier is
made as much deeper than the outer floating pier as will keep the part of the
.bridge which rests upon it at such a level as will make the top of the roadway
of the bridge as nearly as possible one continuous line of inclination. And
.although in the different Drawings I have shewn the roadways to be of such a
breadth, as only to allow of one line of carriageway, yet where the traffic
great I make the roadway with a double line, one for carriages, carts, or
-waggons going down the pier, and the other for those coming up. And in
cases where one floating pier would not give the necessary accomodation, I
employ two or more floating piers, with buttresses between them, and a buttress
at each extremity, and carry a moveable bridge from the centre of each of
such floating piers to the wharf or jetty.
is
Now having described the first part of my Invention, I declare that I do
not claim the principle of constructing low-water piers with a fixed pier, a
floating pier, and a bridge connecting them, as I am aware that piers for foot
.passengers with these arrangements have been hitherto constructed and are
at present in use; but what I claim is this peculiar construction of low-water
piers adapted for all kinds of traffic, and for the accomodation of all classes of
vessels, in loading or delivering passengers or goods of all kinds, at any state
of the tide, without the intervention of stairs between the fixed and floating

page_text: piers, and, which piers form proper roadways for carriages, carts, waggons, or
other vehicles, even of the heaviest description, coming to or going from such.
vessels lying alongside the floating piers; and when such piers are to be
adapted for ferrys, the floating piers may be made of such a height that their
decks will be level with the decks of steamers or other vessels used for the
ferry, so that any carriage or vehicle may drive down the pier and on board
such steamers or vessels without disengaging the horses, and which piers are
constructed in the peculiar manner shewn in the accompanying Drawings, and
described herein.
The next part of my Invention consists of an improved method of con-
structing floating breakwaters or sea barriers for the protection of shipping
in harbours, estuarys, or other inlets of the sea. This part of my Invention I
have represented in Sheet No. 4, and in the different Figures the same letters
refer to similar parts.
Figure 1 is a transverse section of a floating breakwater, which may be
moored in any position, in order to protect any vessel from the force of the
waves, &c. to which they may be exposed; Figure 2 is a longitudinal elevation
of the same; and Figure 3 is a plan of two of these breakwaters coupled
together, shewing the manner in which the breakwaters may be connected.
Now although I have only shewn here two breakwaters, there may be any
number employed, according to the extent of the entrance of the harbour of
estuary to which such breakwaters are to be applied; and although I have
shewn these breakwaters coupled together in the manner represented in the
Drawing, I do not confine myself to this mode of coupling them, as I may
sometimes do so by means of bars, with balls and socket joints, in order to
allow any degree of play between the breakwaters thus connected. A, A, is
a caisson or floating vessel formed of plate iron, which forms the principal
buoyant part of the breakwater, and which has tubes or funnels going through
it horizontally, so that from its cylindrical form, and being stayed by these
tubes, it will be of great strength. To this are affixed beams of (T) iron, B, B,
upon which the planks C, C, C, are securely bolted, and these planks, together
with the (T)-iron beams and other bars, form a framework by which the
force of the waves is broken. Through the funnels or horizontal tubes in the
caissons the sea will also break, so as to make the water comparatively smooth
on the inside. These breakwaters are moored in the required positions by the
chains D, D, D, to which are affixed anchors or other mooring apparatus.
E, E, is an iron box suspended below the breakwater by T-iron bars strongly
affixed to the floating caissons, into which box ballast is introduced by the
vertical tubes F, F, F, which ballast by its gravity tends to keep the break-

page_text: water always in its proper position, and is necessary in order to sink the
caisson in the water to the necessary depth.
Having thus described the second part of my Invention, I may state that I
do not claim the Invention of floating breakwaters of iron or other material;
but what I claim is, the forming of floating breakwaters in the peculiar
manner represented in the Drawing, and described therein.
In witness whereof, I, the said Peter Borrie, have hereunto set my hand
and seal, this Twenty-first day of June, in the year of our Lord