IMPROVEMENTS IN APPARATUS OR MEANS FOR PROTECTING THE SCREW OF STEAMERS FROM BECOMING ENTANGLED WITH OR FOULED BY ROPES OR OTHER BODIES
Year: 1862

page_text: LETTERS PATENT to William Nelson Hutchinson, of Plymouth, in the
County of Devon, Major-General in Her Majesty's Army, for the
Invention of "IMPROVEMENTS IN APPARATUS OR MEANS FOR PROTECTING
THE SCREW OF STEAMERS FROM BECOMING ENTANGLED WITH OR FOULED BY
ROPES OR OTHER BODIES."
Sealed the 1st May 1863, and dated the 6th November 1862.
PROVISIONAL SPECIFICATION left by the said William Nelson Hutchinson
at the Office of the Commissioners of Patents, with his Petition;
on the 6th November 1862.
I, WILLIAM NELSON HUTCHINSON, of Plymouth, in the County of
Devon, Major-General in Her Majesty's Army, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN APPARATUS OR MEANS
FOR PROTECTING THE SCREW OF STEAMERS FROM BECOMING ENTANGLED WITH, OR
FOULED BY ROPES OR OTHER BODIES," to be as follows:-
My Invention consists in the employment of a sheet on each side of the
quarter or after part of the ship, composed by preference of two, three, or more
thicknesses of canvas waterproofed or of vulcanized india-rubber. These
sheets are of rectangular shape. The upper edges are sustained by corks or
buoys and are kept in a vertical position in the water by the bottom being

page_text: leaded or by metal netting attached to it. The sheets are attached to the
ship on one perpendicular side by means of brackets which play freely in a
groove in a guide bar provided for the purpose, while a rope or chain retains
the opposite side of the sheet. The flexibility of these sheets allows of their
readily and slightly yielding to the pressure of passing objects which they push
or guide away from the screw.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Nelson Hutchinson in the Great Seal Patent Office
. on the 6th May 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
NELSON HUTCHINSON, of Plymouth, in the County of Devon, Major-General
in Her Majesty's Army, send greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixth day of November in the year of our Lord
One thousand eight hundred and sixty-two, in the twenty-sixth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said William Nelson Hutchinson, Her special licence that I, the said William
Nelson Hutchinson, my executors, administrators, and assigns, or such others as
I, the said William Nelson Hutchinson, 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 APPARATUS OR MEANS FOR PROTECTING THE
SCREW OF STEAMERS FROM BECOMING ENTANGLED WITH OR FOULED BY ROPES OR
OTHER BODIES," upon the condition (amongst others) that I, the said
William Nelson Hutchinson, my executors or administrators, by an instru-
ment 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 imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said William Nelson Hutchinson, do hereby
declare the nature of my said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and by the

page_text: following statement thereof, reference being had to the Drawings hereunto
annexed, that is to say:-
My Invention consists in the employment of a flexible screen or net
on each side of the quarter or after part of the ship, and both fore and
aft of the screw hanging nearly vertically, composed in the upper part
of several folds of strong waterproofed canvas or other suitable material
or materials and partly sustained in the water by corks or a spar of
light wood. The remainder of the screen may be a net (chain or otherwise)
of large meshes, say 18 inches wide (made of metal or other suitable material)
which being thin offers little resistance to the sea, and therefore is not liable
to be injured by a sea striking it nor to impede the ship's progress. In ships
with fine runs I prefer to form the whole screen of net made with Newall's
galvanized wire rope.
The annexed Drawings illustrate the manner in which I
carry my Invention
into effect supposing the entire screen to be formed of network.
Figure 1 is an external elevation of so much of the stern and quarter of a
ship with my screen fitted thereto as is necessary for the explanation of my
Invention.
A, A, is a grooved metal guide bolted to the ship's side shewn in cross
section at Figure 2. B is a chain composed of a series of L-plates or links,
a plan of one of which is shewn at Figure 3, and a section at C, Figure 2. The
flanges on these links work in the grooved guide A.
a, is an eye in these links serving the double purpose of holding a wire or
cord 6 for connecting the links together, and also of having the fore end of
the fore part of the screen attached thereto. D is a bar which plays freely
within the groove in the grooved guide A, to which bar the uppermost of the
1-links is attached, whereby the fore end of the foremost screen is raised and
lowered as required. The after part of the foremost screen is attached to
a rod E. To the inside of this rod and at about the centre thereof another
cord is connected and carried through an eye bolt fixed in the quarter or side
of the ship and on deck. This cord and eye bolt are not shewn in the
Drawing. The rod E is held from the deck by a rope or chain c
while the screen attached to it is kept extended towards the screw
aperture by another rope d carried through an eye in the lower part
of a bar F free to be moved up and down in a groove fixed on the ship's side,
or the bar F may be retained in position by brackets. The after screen is
held and fitted as next described, I fix a curved metal slotted
detached in side elevation at Figure 4 and in section at
tube G shewn
Figure 5 to

page_text: the stern of the ship and supported by a metal bar e, which is bent to allow
of the play of the rudder. A curved bar H of the form shewn at Figures 4
and 5 fits in and is free to travel up and down in the tube G when pulled
upon from the deck by ropes f, g; eyes h serve as means for attachment of
the after end of the after screen. The top of this screen is connected to the
bar I and the fore end to the bar K, a rope i is carried from the bars I
and K through the eye in the bar F, on to the deck and by being tautened
keeps the screen in the position shewn in the Drawing.
The whole of my screen is capable of being fixed within limits at any required
level and the fittings are such that when required it can be entirely removed.
When removed I prefer that the nets be detached from the links C and from
the bar H, and that the said links and bar be replaced in the grooved guide
A and tube G that by being occasionally worked up and down all growth
of weeds may be prevented. All extraneous matter could be completely cut
away were a sharp edged scraper conforming in shape to the groove to be
occasionally attached to the lowest link of the chain and in a similar manner
a scraper to the bottom of the rod.
Now
The Drawing shews the screen in position for protecting the screw.
supposing it be desired for any purpose to raise the whole screen or part
only, I proceed as follows:-I let go the rope d, raise the bar D, and
In like
haul in the rope c, when the fore screen may be taken inboard.
manner I let go the rope i, and haul in the rope f, when the after screen
may be taken inboard. I then haul up the bar F, and all is snug. Now
to refit the screens I reeve the ropes d and i through the eyes in the bar F,
reship and push it down in its groove (or through brackets) insert the chain
B and the bar D in the grooved guide A, lower the bar E, and haul the d
Then for the after screen I insert the end of the curved bar H in
the slotted tube G, its own weight will carry it down in the tube assisted
by pulling gently on the rope 9 and I haul the rope i taut. When the
ship is being propelled astern, I find it advantageous to make the fore screen
bear close against the quarter, and this is effected by pulling on the rope
before mentioned as not shewn in the Drawing.
taut.
rope
The substances that foul a screw either float or are attached to sub-
stances which float, and as the nets lie in a diagonal direction, they push
aside such substances as the ship progresses. Were the nuts forced in by
any unusual pressure they would be driven in clear of the blade of the
screw.
And having now described the nature of my said Invention and in what

page_text: manner the same is to be performed, I declare that I claim the employment
of flexible screens or apparatus for protecting screw propellers whether
composed of canvas or other like close material or of openwork fabric such
as netting fitted and worked substantially in manner herein-before described
and represented in the accompanying Drawings.
In witness whereof, I, the said William Nelson Hutchinson have here-
unto set my hand and seal, this Second day of May One thousand
eight hundred and sixty-three.
W. N. HUTCHINSON. (L.S.)
Major-General.