IMPROVEMENTS IN ANCHORS AND MEANS FOR SINKING THE SAME
Year: 1876

page_text: LETTERS PATENT to Pryse Protheroe, of Surbiton, in the County of Surrey,
for the Invention of "IMPROVEMENTS IN ANCHORS AND MEANS FOR SINKING
THE SAME."
Sealed the 22nd August 1876, and dated the 14th June 1876.
PROVISIONAL SPECIFICATION left by the said Pryse Protheroe at the Office
of the Commissioners of Patents on the 14th June 1876..
PRYSE PROTHEROE, of Surbiton, in the County of Surrey.
ANCHORS AND MEANS FOR SINKING THE SAME."
"IMPROVEMENTS IN
My Invention has reference to an improved construction of and means for sinking
anchors whereby I am enabled to imbed them readily to any desired depth in sand,
mud, or other soft soil.
For this purpose I construct the anchor with a hollow shank open at both ends,
at the lower end of which I fix, by preference, a disc of cupped or spherical shape.
To the upper end of the hollow shank I fix a flexible or jointed tube, and when the
anchor has been lowered on to the bed of the river, sea, or other water, I force a
current of water or air down through the tube and slank, so that as it issues from
the lower end thereof underneath the cup-shaped disc, it washes away the sand
or soil from underneath the same, and thus allows the anchor to sink by its weight
into the sand, which will close in over the upper surface of the disc and thus hold
the anchor securely imbedded.
Although I prefer to make the disc of a cup shape as described, yet it may also
be flat or conical, or it may consist of a number of curved or inclined ribs, and
these may either be rigidly fixed or they may be hinged to the shank so that they
will fold inwards somewhat as the anchor descends and spread outwards when a
pull is put upon the anchor.
Also, in order to increase the holding power of the anchor when sunk, I either
provide in the cup-shaped disc sliding ribs that may be made to project up beyond
the periphery of the disc by hauling a chain passing through guides on the shank
and disc and connected to the ends of the sliding ribs. Or ribs may be hinged to
the periphery of the disc, so that as it sinks they are in a vertical position, but
when it has been sunk they will spread out on any pull being put upon the anchor.
The injected water may in some cases be made to issue through a number of
LD SJ1

page_text: openings formed in the surface of the disc or of the shank, instead of only at the
lower end of the latter, as described.
To the upper end of the shank may be attached a ring and mooring chains in a
similar manner to ordinary anchors.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Pryse Protheroe in the Great Seal Patent Office on the 5th December
1876.
PRYSE PROTHEROE, of Surbiton, in the County of Surrey.
ANCHORS AND MEANS FOR SINKING THE SAME.'
"
"IMPROVEMENTS IN
My Invention has reference to an improved construction of and means for sinking
anchors whereby I am enabled to imbed them readily to any desired depth in sand,
mud, or other soft soil.
For this purpose I construct the anchor with a hollow shank open at both ends,
at the lower end of which I fix, by preference, a disc of cupped or spherical shape.
To the upper end of the hollow shank I fix a flexible or jointed tube, and when the
anchor has been lowered on to the bed of the river, sea, or other water, I force a
current of water or air down through the tube and shank, so that as it issues from
the lower end thereof underneath the cup-shaped disc it washes away the sand or
soil from underneath the same and thus allows the anchor to sink by its weight
into the sand, which will close in over the upper surface of the disc and thus hold
the anchor securely imbedded.
Although I prefer to make the disc of a cup shape as described, yet it may also
be flat or conical, or it may consist of a number of curved or inclined ribs, and
these may either be rigidly fixed or they may be hinged to the shank so that they
will fold inwards somewhat as the anchor descends and spread outwards when a
pull is put upon the anchor.
Also, in order to increase the holding power of the anchor when sunk, I either
provide in the cup-shaped disc sliding ribs that may be made to project up beyond
the periphery of the disc by hauling a chain passing through guides on the shank
and disc and connected to the ends of the sliding ribs. Or ribs may be hinged to
the periphery of the disc, so that as it sinks they are in a vertical position, but
when it has been sunk they will spread out on any pull being put upon the anchor.
The injected water may in some cases be made to issue through a number of
openings formed in the surface of the disc or of the shank, instead of only at the
lower end of the latter, as described.
To the upper end of the shank may be attached a ring and mooring chains in a
similar manner to ordinary anchors.
DESCRIPTION OF THE DRAWINGS.
Fig. 1 represents a vertical section of. one form of anchor according to this In-
vention. It consists of a heavy bowl-shaped or conical part N, having fixed to it
a hollow stem or tube O.open at the bottom, and connected at the top to a flexible
or jointed tube leading to a force pump on board ship. The anchor having been
lowered to the bottom a stream of air, or preferably water, is forced down through
the stem O, so as in issuing underneath the anchor to wash away the sand or mud
and thus allow it to sink. When it has been sunk to some depth the sand or mud
subsiding over it opposes resistance to its removal; the flexible or jointed tube may
thereupon be removed. In order to increase the holding power of the anchor,
without materially increasing resistance to its descent, it may be provided with
While the anchor is
hinged flukes Q, as shewn in the side views Figs. 2 and 3.
descending in the soft material of the bottom the flukes Q are directed vertically
upwards, as shewn in Fig. 2, but after it has become imbedded, when force is

page_text: applied to withdraw the anchor, the flukes spread outwards, as shewn in Fig. 3,
their connection to the body N of the anchor being made by stop joints that
prevent them from spreading out farther.
Instead of employing a hollow or tubular stem for anchors of the kind described,
they may be attached to the mooring chain or cable by two or more shackles R,
as shewn in the vertical section Fig. 4, the flexible tube O being attached to a
socket at the bottom of the cup. Also, instead of employing a single orifice for
cjecting the fluid current numerous orifices may be provided, as shewn in Fig. 4.
Having thus described the nature of my Invention, and in what manner the
same is to be performed, I claim―
First. The method, substantially as herein described, of sinking an anchor in a
soft bottom by injecting under the body of the anchor a stream of fluid so as to
displace the material beneath the anchor.
Second. The use, for operating in the manner above referred to, of an anchor
consisting of a cup-shaped or conical piece with or without flukes jointed thereto,
the said piece having at its bottom one or more orifices communicating by a flexible
or jointed tube with a force pump, substantially as herein described..
In witness whereof, I, the said Pryse Protheroe, have hereunto set my hand and
seal, this Sixth day of November, in the year of our Lord One Thousand
eight hundred and seventy-six.
PRYSE PROTHERUE. (L.S.)