Year: 1888

page_text: Date of Application, 1st Mar., 1888
KC.
Complete Specification Left, 14th Dec., 1888
Complete Specification Accepted, 22nd Jan.. 1889
I, EDWARD CROFT GREENWAY THOMAS of No. 1 Beacondale Road Norwood in
the County of Surrey Gentleman do hereby declare the nature of this invention to
be as follows:-
My invention relates to appliances whereby the strain on anchors or other fixed
moorings caused by the action of waves on the vessels or bodies moored can be more
or less relieved. For this purpose I attach to the mooring cable hollow cones
presenting their open bases backwards towards the moored vessel. I place these what
may term arrow-head moorings at such parts of the cable that the part of the
wave which they occupy is the slope opposite to that occupied at the same moment by
the vessel. As the particles of water on the one slope of a wave are moving in a
direction opposite to that in which the particles on the other slope are moving at the
same time, so the force applied by the wave particles to the arrowhead moorings
opposes the force which at the same moment is acting on the vessel and consequently
the strain on the fixed mooring is proportionately relieved.
ABEL & IMRAY,
Agents for the Applicant.

page_text: Improvements in Moorings for Vessels and other Floating Bodies.
I, EDWARD CROFT GREENWAY THOMAS of No. 1 Beacondale Road Norwood, in
the County of Surrey Gentleman do hereby declare the nature of this invention
and in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement :-
My invention relates to appliances whereby the strain on anchors or other fixed
moorings caused by the action of waves on the vessels or bodies moored can be more
or less relieved.
For this purpose, I attach to the mooring cable hollow cones presenting their open
bases backwards towards the moored vessel. I place these what I may term " arrow
head moorings" at such parts of the cable that the part of the wave which they
occupy is the slope opposite to that occupied at the same moment by the vessel. As
the particles of water on the one slope of a wave are sometimes moving in a direction
opposite to that in which the particles on the other slope are moving at the same time
and sometimes quiescent while the others are progressing, so the force applied by the
wave particles to the arrow head moorings opposes the force which at the same
moment is acting on the vessel; the forces thus counterbalance one another, and
consequently the strain on the fixed mooring is proportionately relieved. The position
of the arrow-head moorings must depend in each case on the magnitude of the waves
where they are applied. When arrow head moorings are used to relieve the strain
on a cable mooring a vessel, they should be fixed on the cable at such distances from
the vessel as to be always in hollows when a wave crest meets the vessel, or on crests
when the hollow meets the vessel. By spacing them at these distances, they are
always subject to the action of water particles moving in a direction opposite to the
movement of those which are for the time acting on the vessel.
Consequently when the vessel is urged by a wave away from its anchor or fixed
mooring, the arrow head moorings are at the same time.urged by the waves towards
the anchor or fixed mooring, the strain on which is therefore proportionally relieved.
The arrow head moorings may be hollow cones of metal, wood, canvas or other
material each presenting its apex towards the coming waves or to the particles of
water moving towards it and towards the vessel and therefore presenting its base
towards the water particles that move from the vessel. Or each arrow head mooring
may consist of two wooden shutters meeting at an angle where they may be hinged
together, stops being provided to provent them from opening too far apart and
from entirely closing together, or it may be rigid in V form. The water particles
moving towards the vessel tend to close them together when hinged and easily pass
them, and the particles in their return movement tend to open them apart and urge
them towards the fixed mooring at the time when the vessel is being urged away
from the fixed mooring.
Another application of the same principle is to attach the arrow heads to the vessel
itself by placing a line of hinged shutters along each side of the vessel so fixed as to

page_text: permit of their closing and lying nearly flat along side with the incoming swing of a
wave and opening to an angle of about 80 degrees with the outgoing swing; a spring
or cord and weight over a pulley may also assist the shutters to take this latter
almost rectangular position; this method would only be useful when a vessel's length
nearly equals at least the space between two waves.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
Fixing on the cable which holds a vessel or other floating body to a stationary
body, or along the side of the vessel itself, arrowhead moorings presenting their
apices towards the stationary mooring and spaced at such distances from the vessel
or moored body, relatively to the wave length, that they are pressed by the water
particles constituting the waves in a direction opposite to that in which the vessel or
moored body is simultaneously pressed or at least kept stationary; and thus retard
movement towards land substantially as and for the purpose herein set forth.
Dated this 14th day of December 1888
ABEL & IMRAY,
Agents for the Applicant.