IMPROVEMENTS IN PROPELLING VESSELS AND IN STEERING VESSELS
Year: 1847

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
HENWOOD, of Portsea, in the County of Southampton, Naval Architect, 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 Fourth day of May, One thou-
sand eight hundred and forty-seven, in the tenth year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said William
Henwood, my exors, admors, and assigns, Her especial license, full power, sole
privilege and authority, that I, the said William Henwood, my exors, adiñors,
and assigns, and such others as I, the said William Henwood, my exors,
admors, 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
PROPELLING VESSELS AND IN STEERING VESSELS;" in which said Letters Patent is
contained a proviso that I, the said William Henwood, should cause a par-
ticular 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
more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, 1, the said
William Henwood, do hereby declare that the nature of my said Invention,

page_text: 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:-
One of my improvements in propelling and steering relates to screw pro-
pelled ships or vessels. It consists in placing the scrow propeller at the aft
side of the stern post, where the rudder is in vessels generally, and in applying
the rudder on the foreside of the screw propeller, in the lower and aftermost
part of the run, and below the propeller shaft, the rudder being substituted for
the same part of the run of the vessel. See Drawing I., Figure 1. The lower
end of the stern post meets the keelson or timber running under the shaft at
about the height of the centre of the shaft, and the one may be united very
securely to the other by a flanch or flanches on the shaft cylinder. Figure 2, let
into and bolted to the stern post and keelson. This keelson or timber should be
large in siding, because of the hole through it for the rudder head to pass
through, and it must have a rabbet to receive the bottom plank. The pro-
peller is connected with the stern post and vessel very firmly by a metal
coupling box a, Figures 1, 4, and 5, which has a metal frame h attached
to it for raising and lowering the propeller, the coupling box and hoisting
frame being formed with tongues to slide in metal-faced grooves in the sides of
tho stern posts, and the coupling box having an interior collar of the utmost
requisite strength, fitted against a corresponding exterior collar round the pro-
peller, Figures 1 and 4. The union of the ship to the propeller is thus made
abundantly strong for pressing the shaft into the propeller and for "backing
astern." An after-bearing for the shaft may be formed by a metal rod e,
Figures 1, 3, set up with a screw to the stern, which rod would also form an
additional stop for the propeller on the shaft in backing astern; or a rod
might be attached to the upper and after part of the hoisting frame, and set
up with a screw to the vessel's stern; and a small rod e, Figure 6, may be
applied at the aftside of the hoisting frame, for inserting a forelock in the end
of the shaft, to secure the propeller in backing astern, which forelock would
revolve with the shaft on the pin at x. The surface of the rudder may be as
large as that of the immersed part of the common rudder, as it is in Figure 1,
although as the pressure of the water on such a rudder would be once and a
half as great as on the common rudder, a much smaller surface would be
*sufficient for steering, and the lower part might be reduced similarly to that in
Figures 1, 2, 8, in Drawing 2. A large and very strongly formed rudder band
is fitted at the upper part of the rudder, with a large hole through it, of a
square, hexagonal, or other form, into which tho rudder head 1, Figure 1, is
fitted for turning the rudder; the lower rudder band might also be formed

page_text: similarly, and the braces fitted with an internal ring, that the rudder head
being extended downward as a substitute for the rudder pins, may revolve in
the braces, whilst it is fixed in the rudder bands for turning the rudder. The
rudder head above the upper rudder band is cylindrical, and passes through a
metal cylinder with a suffing box; it then surrounds the propeller shaft, Figure 7,
so that the rudder may turn sufficiently in steering, and it extends to any
convenient height to receive the tillar. Should the rudder be carried away, a
temporary rudder could be applied, by taking up the propeller, using sails only,
and having the temporary rudder prepared with braces to slide down the stern-
post grooves, by which it would be held securely to the ship, its lower end
being secured with guys. The advantages to be obtained from this improve-
ment are the maximum effect of the screw propeller in propelling, the
avoidance of risk of serious damage from a vessel's grounding, and the pre-
servation of the strength and the form, and the displacement of the after part of
vessel. I claim the right to apply a screw propeller and a rudder conjointly
to a ship or vessel in the positions above-mentioned, and as shewn on the
Drawing.
My improvement in steering vessels consists also in applying a similar
rudder to a ship or vessel not propelled by a screw. Figure 1, Drawing 2,
shows such a rudder for a first-rate ship of war; Figure 2 shows one for a
large man-of-war brig, and Figure 3 for a small merchant vessel. Such a
rudder could be either shipped or unshipped afloat, by attaching a water-tight
hose or cylinder to the rudder head cylinder, so that the rudder head r, with
rudder pin cr pins attached to it, may be drawn up in unshipping the rudder
or replaced in shipping it. The keel may extend under the rudder as shewn,
Figures 1, 2, 3, to protect it in grounding. The advantages of such a rudder
are, much less first cost, indefinite durability through being always under water,
being below the impulses of waves, so that steering would be uniformly steady,
and without hazard to the helmsman, both when a ship is laden and when
she is light, and it is quito below the reach of shot. Should a vessel lose her
rudder by getting ashore, a temporary rudder could immediately be applied by
having braces fitted specially for it, as b, b, b, Figure 1. I claim the right of
applying such a rudder to a ship or vessel.
My other improvement in propelling vessels relates to ships or vessels of all
kinds. It consists in making that part of the immersed volume which is abaft
the vertical and transverso plane in which the centre of gravity of the vessel is
of such a form that the longitudinal stability of the after end of the vessel may
be practically equal to that of the fore end, in order that the pitching motion,
so far as it may be caused by the form of the immersed volume, may be pre-
vented, and that there may be the least possible resistance of the water to the

page_text: propelling power. This is of especial importance in screw propelled vessels,
because pitching raises the screw above the water's surface. The equal stability
of the fore and the after ends of a ship is obtained by making the area of the
load water section abaft the above-mentioned vertical and transverse plane
equal to the area of the remaining part of the same water section on the fore
sido of the said plane, and the moments of those areas from the same vertical
and transverse plane also equal, and by forming the lower horizontal sections
. or water lines in a similar manner, or so that the cubic contents of the
immersed volumes on each side of the same vertical and transverse plane, and
the moments of the same immersed volumes from the same plane shall like-
wise be equal the one respectively to the other. A vessel of remarkable beau-
tiful form may thus be produced. As the propelling power of the wind on the
sails always depresses the fore end of a ship when it impels her onwards, just
as it depresses the lee side when the wind acts obliquely, it appears contrary to
the dictates of reason and of science, that ships should have, as they commonly
have, less stability at the fore end than at the after end. By making the
stability equal at both ends of a ship, the pitching would be reduced to the
least possible degree, the propelling power would produce greater speed, the
decks or gun platforms would be kept more nearly in their horizontal positions,
and the dangers and discomfort and expense of "wear and tear" in rough
weather would be materially diminished.
I claim the right of making ships or vessels of the form above described, so
that the longitudinal stability of the fore end may be practically equal to that
of the after end.
the
In witness whereof, I, the said William Henwood, have hereunto set
my hand and seal, this Fourth day of November, in the year of our Lord
One thousand eight hundred and forty-seven.
year
WILLIAM (L.S.) HENWOOD.
AND BE IT REMEMBERED, that on the Fourth day of November, in
of our Lord 1847, the aforesaid William Henwood came before our
said Lady the Queen in Her Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained and specified, in form
above written. And also the Specification aforesaid was stamped according
to the tenor of the Statute made for that purpose.
Enrolled the Fourth day of November, in the year of our Lord One
thousand eight hundred and forty-seven.