An Improvement in the Form of Ships.
Year: 1895

page_text: Date of Application, 2nd Dec., 1895
Complete Specification Left, 2nd Sept., 1896-Accepted, 17th Oct., 1896
PROVIDIUNAL DIECIFICATION.
An Improvement in the Form of Ships.
I, OTTO HARTWICH, of Swinemünde, Prussia, Shipbuilder, do hereby declare
the nature of this invention to be as follows:-
--
The ordinary form of the bow and the water-line-plan of sea going ships,
whether they are narrow or broad are such as to encounter great resistance in the
water.
The greater the velocity of the vessel, the more obvious it is that the vertical
cutting through of the waves in front acts prejudicially, as the masses of water are
caused to rise against the bow increasing thereby the wetted surface, and as the
water-line-plan is such as not to permit these masses to flow off freely rearwards,
the resistance of the whole ship's-body in the water is very much increased. In
order to avoid these evils I have devised a form for a ship to offer the least
resistance without interfering with the stability or with the capacity of the vessel,
as I shall now describe.
In the first place I modify the shape of the fore-part of the vessel in such a
manner, that instead of its vertically cutting through the water, it cuts horizontally
through it so that one portion of the water is led off upwards and the other portion
downwards. At the same time the water-line-plan and the body-plan of the vessel
are so formed that the portion of the water which is led away downwards and
passes under the body of the ship does not retard the vessel, but rather aids its
motion, while the portion of the water which is led away upwards owing to the
peculiar shape of the water-line-plan, is so conducted that the resistance is a
minimum.
For this purpose, in the first place I extend under the water-line a prow some-
what like a ram but horizontally broad and vertically narrow with a rounded front
to cut the water horizontally.
Secondly the cross section of the ship-body joining by certain curves this
projecting prow and the plan are such that the immersed part of the body is
largest immediately behind the prow and decreases towards the stern first gradually,
then more rapidly.
Thirdly, the hull is suddenly contracted just above the water-line, the greatest
width being below the water-level in a part which is rounded off, and which, being
at its outer part about level with the keel, turns inwards and upwards to less
depth along the longitudinal centre line of the vessel thus presenting a hollow
along the bottom divided by the keel. This section and the plan resulting from
it ensure great stability. In order to give the vessel great facility for manoeuvring
I provide a bottom rudder immediately behind the prow occupying part of the
keel space and completely protected by the bottom being also entirely surrounded
by the water under the vaulted bottom, it becomes immediately active on the least
turning on its vertical axis.
Dated this 2nd day of December 1895.
ABEL & IMRAY,
Agents for the Applicant.

page_text: An Improvement in the Form of Ships.
I, OTTO HARTWICH, of Swinemünde, Prussia, Shipbuilder, 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 :-
The ordinary form of the bow and the water-live-plan of sea going ships,
whether they are narrow or broad, are such as to encounter great resistance in the
water. The greater the velocity of the vessel, the more obvious it is that the
vertical cutting through of the waves in front acts prejudicially, as the masses
of water are caused to rise against the bow, increasing thereby the wetted surface,
and as the water-line-plan is such as not to permit these masses to flow off
freely rearwards, the resistance of the whole ship's body in the water is very
much increased.
In order to avoid these evils I have devised a form for a ship to offer the least
resistance without interfering with the stability or with the capacity of the vessel
as I shall now describe.
In the first place I modify the shape of the fore-part of the vessel in such a
manner that, instead of its vertically cutting through the water, it cuts horizontally
through it, so that one portion of the water is led off upwards and the other
portion downwards. At the same time the water-line-plan and the body-plan of
the vessel are so formed that the portion of the water which is led away down-
wards and passes under the body of the ship does not retard the vessel, but
rather aids its motion, while the portion of the water which is led away upwards
owing to the peculiar shape of the water-line-plan, is so conducted that the
resistance is a minimum.
For this purpose 1 construct a ship as I will describe with reference to the
accompanying drawing, in which Fig. 1 shews a side elevation, Fig. 2 a half plan,
Fig. 3 a cross section, Fig. 4 a front end view, and Fig. 5 a diagram of the lines
of transverse section.
In the first place I construct the fore part A of the ship with a broad flat
prow B extending under water, something like the ram of a warship, and which
curves gradually upward to the rounded stem of the ship, the said prow being
rounded in front and formed with a concave underside. Its action is to divide
the water in a horizontal direction into a part passing upward and a part passing
downward, such latter part escaping into the said concave space formed under the
bottom of the prow as shewn at Fig. 4.
Secondly, the cross section of the ship-body is of such forin as to join by
certain curves on to the said prow, in the manner shewn at the water-line-plan
at Fig. 2, the lines being so formed that the immersed part of the ship is widest
in cross section immediately behind the stem and decreases in width from that
point towards the stern, first gradually, and then more rapidly, forming at the
stern a comparatively sharp edge.
Thirdly, the hull is suddenly contracted with a concave curvature from a point
below water-line to a point above it, as shewn at Fig. 3, so that the greatest width
of the ship is below the water level, in a part which is sharply rounded off down-
wards and which, being at its lowest outer part nearly level with the keel, rises
thence inwards in a concave curvature to form the concave ship's bottom C which
is divided longitudinally by the projecting keel D.
The above described form of section and the plan resulting from it will
ensure great stability for the ship, with a minimum of heel, while at the same
time the peculiar curves employed in forming this shape are such as to offer the
least frictional resistance.

page_text: In order to give the ship thus constructed great facility for manœevering,
I provide it with a bottom rudder E arranged immediately behind the projecting
prow A and occupying the position of part of the keel, being made of the same
depth as the latter, so that it is completely protected by the ships bottom, and
being also entirely surrounded by the water contained in the concave space under
the bottom, it becomes immediately active on being turned to the slightest degree
on its vertical axis. This feature is of particular value in comparison with the
action of such rudders of known construction.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed I declare that what I
claim is :-
1. A construction of ship wherein, on the one hand, the waterline plan is formed
by curves which give the greatest width to the ship immediately behind the stem,
decreasing from that point continuously rearwards so as to converge to a sharp
angle at the stern, while on the other hand the hull is contracted in cross section
from a point below the waterline to a point above it, the widest part being below
waterline, at about the level of the keel, where it is sharply rounded inwards to
join on to the concave bottom of the ship, this being divided by a projecting keel
substantially as herein described with reference to the drawing.
2. In the construction of ship set forth in the preceding claim, extending the
bows of the ship below waterline to form a flat broad prow B, connected to the
stem by an upward curvature, and having a concave underside joining on to
the concave bottom of the ship, which prow divides the water horizontally into a
portion which passes upward, and a portion which passes downward and escapes
under the concave bottom, substantially as described with reference to the
drawing.
3. In the construction of ship referred to in the first and second claims, the use
of a bottom rudder E occupying the position of part of the keel and having the
same depth as this, such rudder being entirely covered by the downward projecting
sides of the ship, substantially as described with reference to the drawings.
Dated this 2nd day of September 1896.
ABEL & IMRAY,
Agents for the Applicant.