IMPROVEMENTS IN BREAKWATERS
Year: 1869

page_text: LETTERS PATENT to Stephen Alley, of the Firm of Carruthers and
Alley, of Glasgow, in the County of Lanark, North Britain, Engineer,
for the Invention of "IMPROVEMENTS IN BREAKWATERS." -A commu-
nication from abroad by John King, residing in Chili.
Sealed the 22nd February 1870, and dated the 4th December 1869.
PROVISIONAL SPECIFICATION left by the said Stephen Alley at the
.Office of the Commissioners of Patents, with his Petition, on the .
4th December 1869.
I, STEPHEN ALLEY, of the Firm of Carruthers and Alley, of Glasgow,
in the County of Lanark, North Britain, Engineers, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN BREAKWATERS,"
which Invention has been communicated to me from abroad by John
King, residing in Chili, to be as follows, that is to say :-
This Invention relates to a mode of constructing breakwaters so as to
take advantage of the facts, 1, that the wavy agitation produced in

page_text: water by wind decreases from the surface downwards, and does not
extend to any great depth; and 2, that the motion of the agitated water
being undulatory is accompanied by very little actual forward translation
of the water until the waves reach shallow water, where their destructive
power is principally developed.
The Invention consists in constructing a vertical or nearly vertical
wall of iron or other suitable material to extend to a depth of fifty or
sixty feet below the surface, or sufficiently low to prevent the propagation
under it of the wave action to any effective extent. This wall has its
front surface facing the sea made generally flat and without projections
appreciably obstructing the vertical motion of the water, whilst it is
strengthened at the back by vertical and horizontal or inclined girders
and frames, and has fixed to or formed on its back at the upper part one
or more water-tight compartments which float it. When the sea is
undisturbed the floating compartments will cause the wall to lean
towards the sea so that when the sea is disturbed any horizont pressure
will be so far absorbed in bearing the wall into a vertical posit n, whilst
the large surface of the wall will distribute the pressure on a very
large body of still water behind, and thus effectually resist it with com-
paratively very slight disturbance of the water between the breakwater
and the shore.
The improved breakwater is to be secured to anchors or moorings
situated before and behind it, the chains passing through hawse holes in
the bottom edge of the wall and through pipes to the top of the floating
compartment there to be fastened and tightened or slackened as required,
In tidal waters the chains may be weighted to take up the slack at low
water, and in seas where there is little tide the breakwater may be held
rigidly down to moorings placed directly below it. The structure is to
be made in sections of convenient length horizontally, the lengths being
hinged or otherwise connected together, so as to allow of slight inde-
pendent movements of the separate lengths, and in some cases buffers
or springs may be applied at the connections to assist in restoring the
line after a small displacement of any part.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Stephen Alley in the Great Seal Patent Office on
the 3rd June 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, STEPHEN
ALLEY, of the Firm of Carruthers and Alley, of Glasgow, in the County
of Lanark, North Britain, Engineers, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria,. by Her
Letters Patent, Bearing date the Fourth day of December, in the year
of our Lord One thousand eight hundred and sixty-nine, in the thirty-
third year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Stephen Alley, Her special licence
that I, the said Stephen Alley, my executors, administrators, and assigns,
or such others as I, the said Stephen Alley, my executors, adminis-
trators, and assigns, should at any time agree with, and no othiers,
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 BREAKWATERS,
(a communication to me from abroad by John King, residing in Chili,).
upon the condition (amongst others) that I, the said Stephen Alley, 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.
"
NOW KNOW YE, that I, the said Stephen Alley, 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 statement in writing, reference being had to the accompanying
Drawings, that is to say :-
The said Invention relates to a mode of constructing breakwaters so
as to take advantage of the facts, first, that the wavy agitation produced
in water by wind decreases from the surface downwards, and does not
extend to any great depth; and second, that the motion of the agitated
water being undulatory is accompanied by very little actual forward

page_text: translation of the water until the waves reach shallow water where
their destructive power is principally developed.
The Invention consists in constructing a vertical or nearly vertical
wall to extend to a depth sufficiently low to prevent the propagation of
the wave action under it to any effective extent. This wall has fixed to
or formed on its back at the upper part one or more water-tight com-
partments which float it, and the structure is made in sections of
convenient length horizontally, which are connected together, and
which are secured to moorings situated before and behind them.
And in order that the said Invention, and the manner of performing
the same may be properly understood, I have hereunto appended a
Sheet of explanatory Drawings, to be herein-after referred to and
representing portions of a breakwater as constructed with the im-
provements.
Figure 1 is a plan partly in horizontal section; Figure 2 is a tranverse
vertical section; and Figure 3 is a hack elevation partly in vertical
section.
The Inventor prefers to construct the improved breakwater of iron as
shown in the Drawing, but wood alone or wood combined with iron
may be used in some cases and where more convenient. The structure
is made with a front face 1-2 which is intended to be vertical or nearly
so, and which rises sufficiently high above the normal water level 3-4, to
obstruct the passage over it of large waves, whilst it extends downwards
to a depth, say, of fifty to sixty feet for average situations. This front
face 1-2 is made generally flat and without projections appreciably
obstructing the vertical motion of the water, whilst it is strengthened
at the back by vertical and horizontal girders and frames 5, 6. A water-
tight compartment or casing 7 is formed at the upper part of the back,
and in such a position that when the sea is undisturbed it will cause the
front wall 1-2, to lean with its upper part towards the sea, so that when
the sea is agitated any horizontal pressure will be so far absorbed in
bearing the wall into a vertical position, whilst the large surface of the
wall will distribute the pressure over a very large body of still water
behind, and thus effectually resist it with comparatively very slight dis-
turbance of the water between the breakwater and the shore.
The improved breakwater is to be secured to anchors 8 or moorings 9,
the chains passing through hawse holes 10 in the bottom edge of the
structure, and through pipes 11 to a narrow platform 12 at the top, there
3

page_text: to be fastened to mooring bits 13, and to be tightened or slackened as
required. In tidal waters the chains may have weights 14 applied to
them to take up the slack at low water, and in seas where there is
little tide the breakwater may be held rigidly down to moorings 9 placed
directly below it. The structure is made in sections of convenient
length horizontally, the sections being connected together by hinges 15
or otherwise so as to allow of slight independent movements of the separate
sections, and in some cases buffers or springs may be applied at the
connections to assist in restoring the line after a small displacement of
any part.
Having thus particularly described the said Invention, and the manner
in which the same is to be performed, I have to state that what I believe
to be novel and original, and claim as secured to me by the herein-before
in part recited Letters Patent is, the constructing and arranging of
breakwaters substantially in the improved manner herein.before
described.
In witness whereof, I, the said Stephen Alley, have hereunto set
my hand and scal, this Thirty-first day of May, in the year of our
Lord One thousand eight hundred and seventy.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
STEPHEN ALLEY. (L.S.)