IMPROVEMENTS IN THE CONSTRUCTION OF SHIPS AND OTHER NAVIGABLE VESSELS, AND IN MEANS FOR PROPELLING, VENTILATING, and STEERING THE SAME
Year: 1872

page_text: PROVISIONAL SPECIFICATION left by Robert Atkin at the Office of the
Commissioners of Patents, with his Petition, on the 15th October
1872.
I, ROBERT ATKIN, of Dorset Street, Portman Square, in the County
of Middlesex, Master Mariner, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE CONSTRUCTION OF SHIPS AND OTHER
NAVIGABLE VESSELS, AND IN MEANS FOR PROPELLING, VENTILATING, and STEERING
THE SAME," to be as follows:-
The first part of the Invention relates to a novel construction of ship
or other navigable vessel, whereby great speed, stability, and security
are obtained with a small draught of water, and less propelling power is
required. For this purpose I construct the ship or other vessel in three
parts placed parallel to each other, the centre part being the vessel proper,
whilst the others (one on each side) are to serve the purpose of floats
and to give stability to the vessel, or they may be used to carry a portion
of the cargo. These three parts are connected together at their upper
parts preferably by iron or steel arches, extending from end to end
thereof, so as to leave two longitudinal spaces between the three parts

page_text: of the vessel. All the three parts of the vessel I prefer to form of iron
or steel, the two outer ones being entirely filled with cork or other
buoyant material, whilst the centre or vessel proper is at its lower part
filled with cork or other buoyant material, the space occupied by such
material being below the hold of the vessel and separated therefrom by
a water-tight false bottom. In connection with such vessel and working
in suitable spaces formed in that part of the central vessel which is
filled with cork I employ a number of sliding keels, each of which is
mounted on a separate axis and works independently of the others, so
that any or all of them may be lowered into or raised out of position
for work as may be required by means of chains connected thereto,
and passing up through water-tight tubes fixed between the false
bottom and the deck.
A vessel constructed as above described may be propelled by sails or
steam in any of the well known modes, but I prefer to propel such
description of vessels in the following manner-In each of the two
longitudinal spaces I mount on suitable shafts or axes one or more
screws of large diameter, so that only a portion of the screws shall be
immersed in the water, their shafts or axes being at such a height as to
be always clear of the water. These screws I prefer to place at or near
the midship section of the vessel in order that they may always remain
properly immersed in the water. These screws are provided with
suitable guides and tackle for raising them out of the water or lowering
them into it as may be required. These screws I prefer to form of
wrought iron or steel in the following manner :-I form the screw with a
number of blades (usually cight) each blade being formed separately
and with a scarf or other joint to enable them to be connected together
in pairs. Each pair of blades is formed with a boss in the centre to fit
on the screw shaft, and to fit flat against the adjacent pairs of blades;
then by bolting the various pairs of blades together a complete screw
will be formed which is capable of being readily repaired in case one or
more of the blades should become injured.
If desired cach pair of blades may be made in one piece.
In the longitudinal spaces I also arrange the following apparatus,
which will be put in operation by the motion of the waves and of the
vessel. In each of the aforesaid longitudinal spaces I fix one or more
bags or chambers, the lower or moveable parts of which I form of iron
or steel, and preferably of a curved form, so as to offer as little resistance

page_text: as possible to the motion of the vessel. These lower parts I connect to
the upper or fixed parts by means of vulcanised india-rubber, and I by
preference divide each bag or chamber into two or more parts by india-
rubber partitions, so that in the event of any one of such parts being
rendered inoperative it shall not destroy the utility of all. The upper
or fixed parts of these bags or chambers are formed by the arched
connections between the various parts of the vessel, in the top of which
I fix suitable inlet valves for the admission of air to such bags or
chambers, and to each bag or chamber I also connect suitable ways
or passages leading either to a common reservoir, or I connect them
direct to suitable outlets whence the air may be directed by valves to
propel the vessel in any direction at will. To each of these ways or
passages from the various bags or chambers I apply outlet valves to
permit of the air passing out therefrom, and to prevent its return in that
direction. Within such bags or chambers I apply springs to prevent
the too sudden action thereof, and to prevent the bottoms of the bags or
chambers moving too far in either direction. I also connect to the
bottoms of such air bags or chambers chains which are carried up
through holes in the tops thereof, and are there connected to winches
by which the bottoms of the bags or chambers may when required oe
raised up out of the water. To the bags or chambers I also apply
pressure gauges, and I arrange the inlet valves, so that any one or more
of them may be rendered inoperative as may be desired.
In order to be enabled to employ the air bags or chambers to propel
the vessel in smooth water, I mount on the deck two pairs of shear legs
or other supports, between which I mount a swinging frame to contain
tanks to be filled with water. I then give a swinging motion to such
frame by means of a small steam engine, or by the donkey engine
ordinarily employed on board a vessel for hoisting and pumping
purposes. By these means the vessel is caused to roll to and fro,
thereby alternately filling and emptying the air bags or chambers and
consequently driving the vessel in the direction desired. The common
air reservoir or the bags or chambers are provided with other passages
or valves leading to various parts of the vessel to ventilate the same.
In vessels of the character above described I employ a rudder at each
end, which rudders I mount in steps or bearings at the upper and lower
ends thereof, in such way as to permit of such rudders being completely
rotated on their axes. In addition to the above rudders I also employ

page_text: four other rudders working in the clear water in the longitudinal spaces
between the various parts of the vessel, such rudders being placed at
equal distances from the two ends of the vessel, and having gearing in
connection therewith to raise them out of or lower them into the water
as may be required. These last-mentioned rudders are also capable of
completely revolving on their axes, but have no bearings below the water.
On the upper end of each of the six rudders I mount a toothed wheel,
which is taken into by a pinion or worm to which motion is given by
means of a tiller or steering wheel.
the rudders may be used for steering a vessel of the above construction,
thereby enabling it safely to navigate rivers at a high speed.
By theso means, when required, all