IMPROVEMENTS IN PROPELLING VESSELS
Year: 1843

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
HAMER, of Wardour Street, in the County of Middlesex, Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Victoria the First, by Her Letters
Patent under the Great Seal of Great Britain, bearing date at Westminster,
the Nineteenth day of January, in the seventh year of Her reign, did give and
grant unto me, the said James Hamer, my executors, administrators, and assigns,
Her especial license, full power, sole privilege and authority, that I, the said
James Hamer, my, executors, administrators, and assigns, and such others as I,
the said James Hamer, my executors, administrators, and assigns, should at
any time agree with, and no others, from time to time and at all times here-
after during the term of years therein mentioned, should and lawfully might
make, use, exercise, and vend, within England and Wales and the Town of Ber-
wick-upon-Tweed, my Invention of "IMPROVEMENTS IN PROPELLING VESSELS;" in
which said Letters Patent there is contained a proviso that I, the said James
Hamer, shall cause a particular description of the nature of my said Inven-
tion, and in what manner the same is to be performed, by an instrument in
writing under my hand and seal, to be enrolled in Her said Majesty's High
Court of Chancery within six calendar months next immediately after the said
in part recited Letters Patent, reference being thereunto had, may more fully
and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
James Hamer, do hereby declare that the nature of my Invention, and the
manner in which the same is to be performed, are particularly described and

page_text: ascertained in and by the following description thereof, reference being had to
the Drawing hereunto annexed, and to the figures and letters:-
My improvements in propelling vessels are three in number, of which the
following is a general description, and which I denominate by the numbers
1, 2, and 3.
The first of my said improvements is by the use of air forced through metal
pipes to the stern of the vessel, where by its issuing against the water the
vessel is driven forward.
The second, or improvement No. 2, is by forcing air on the surface of water
contained in horizontal trunks laying longitudinally in the bottom of the vessel,
by the pressure of which air the water is forced towards and out at the stern,
and the vessel thereby propelled forward.
My third and last improvement consists in a method of driving a propelling
screw, of any of the approved kinds, by a rotary steam engine or wheel similar
to what is generally denominated Branca's steam wheel.
In the accompanying Drawing the same letters and figures of reference
refer to the same parts wherever they occur.
My Invention of improvement No. 1 consists of a new method of pro-
pelling vessels through water by means of highly condensed air forced through
tubes, and acting directly upon the water. The air is compressed by means of
condensing air-pumps or cylinders, worked either by a steam engine or any other
power, into an air vessel or vessels, for the purpose of producing a continuous
flow of air of nearly uniform density; and it is forced from the air-vessel
through a tube or tubes leading directly through the ship paralal with the keel.
At each extremity of the ship the said tube, if single, is divided into two
separate branches; one on each side of the keel, and brought out aft either
through the planking or substance of the ship's bottom in the run of the
vessel, or, if thought proper, to carry them out further aft. The strength and
substance of the stern post is by no means reduced in consequence of the two
tubes being brought out one on each side of the stern post, and forward one
on each side of the fore foot, or a single pipe and nozle may be brought
through the stern and fore foot without using any divided pipe, as shewn on
the Drawing. The main tube is divided by a three-way cock, so that the air
may be entirely shut off or allowed to escape either aft or forward. The ends
of the pipes being brought through the planking or substance of the ship's
sides near to the stern post, or in the run of the vessel near the keel, or
through the keel and fore foot, as the case may be, are furnished with nozles
of such diameters as may be found most applicable to the size of the ships and
power of the steam engine, so as to cause. the air to impinge upon the water

page_text: "
with such a force, and in such densities, as may produce the greatest effect in
propelling the vessel through the water. To propel the ship forward, the
engine being set in motion, the pumps are brought into action, the air is
forced through the tubes aft directly against the water, and the vessel is pro-
pelled forward with a rapidity dependent upon the density of the air and the
velocity with which it escapes through the tubes and strikes against the water.
To back her, by turning the three-way cock the air is shut off from the after
part of the vessel, and allowed to escape through the tubes ahead, which are
furnished with nozles similar to them at the stern; the vessel is forced instantly
astern; and by this very simple method the necessity of "backing the engine
is avoided. This method of propelling has a decided advantage over every
other mode in its application to ships of war, as, by inserting a pipe or pipes
at right angles to the main tube, which runs paralal to the keel of the vessel
furnished with a stop-cock or valve, I can, by allowing the air to escape
through either of these tubes, enable a ship of any magnitude to change her
position when becalmed, to steadily rotate upon her own axis of motion, and
thereby prevent herself from being raked by an enemy by bringing her broadside
to bear in any given direction. The great advantage of my method over every
other is most apparent when it is considered, that under the ordinary circum-
stances of navigation a vessel cannot steer without having way upon her,
whereas, by making use of my propeller in the manner above mentioned, she
can, if necessary, shift her position while at anchor. The numerous advan-
tages of this are obvious to any seaman. This effect of rotation on her axes
may be more readily produced by means of four tubes, one coming out on each
side of the quarter aft, and one on each side of the fore part of the ship, when,
by opening that upon the larboard side aft, and the starboard side forward, or
vice versa, she may be turned with still greater facility in any given direction.
Another decided advantage is gained by this power over every other.
In case
of a vessel losing her rudder, as, by causing two pipes to lead from each side
of the main tube in a diagonal direction aft, and come out upon each quarter,
the vessel may be steered or her head steadily kept in any given direction,
without any way being lost, as in the ordinary mode of steering by the action
of the water against the side of the rudder, but from which impediment to her
free progress through the water my method is entirely free.
The division of the Drawing marked 1 represents my first improvement,
No. 2 the second, and No. 3 the third.
་
Reference to the Drawing No. 1-A, A, are two compressing air-pumps,
worked by steam or other power; a, a, pipes of comminication between air-
pumps and receiver; B, an air-vessel or receiver for rendering the flow of

page_text: -air-nearly uniform:--this-air-vessel to be furnished--with-a-safety valve.
C is a three-way cock for allowing the condensed air to flow towards the
stern for propelling forward into the pipes leading forward for backing,
or, by being shut, prevents its escaping into either set of pipes. D, D, is a
metal pipe leading towards the stern for conveying air to the twin pipes
or single pipe, leading through the substance of the vessel or stern post.
E, E, are three stop-cocks for allowing the air to pass direct to the stern for
propelling forward, or to either of the lateral branches for steering marked F, F,
both at head and stern. G is a similar metal pipe leading forward to convey
the compressed air to one or more pipes passing out through or by the side of
the fore foot. To produce a backing motion or side ways for steering I do
not confine myself to any particular disposition or arrangement of the several
parts, or to any dimensions of pumps, pipes, or nozles, except that I make the
orifice of the termination of the pipes or nozles of such a diminitive diameter,
compared to the diameter or capacity of the compressing pumps, that the air,
being confined, except the small escape at the nozles, will become of great
density, and will therefore issue against the water, in a small compact jet, with
very considerable velocity. The density of air in the air-vessel and pipes will
vary from a variety of circumstances; but, in general, it will be found most
advantageous when about equal to the pressure of steam in a high-pressure
steam engine, or say from thirty to eighty pounds on the square inch, the
air-pumps, valves, pistons, and cocks being of the usual kinds, and are so well
understood that any minute description will be quite unnecessary.
My second improvement in propelling is intended chiefly for the use of
canal craft, it being a method by which the disturbance of the water to the
injury of the banks is entirely avoided, and is constructed in the following
manner-Immediately on the top of the floor timbers I lay two trunks
reaching from the bows of the ste , one above the other, slightly inclined
upwards towards the bows. The ends of these, fore and aft, I bring out one
on each side of the fore foot and stern post. In the ends of the trunks at the
bows there is a hinged valve or trap opening inwards, which permits the water
to enter and fill the trunks. In the ends of these trunks, at the stern, there
is a stop reaching from the top of the trunk to within one quarter of the
height from the bottom, which allows the water to be forced out. At the
same time it prevents the escape of air until the water is forced down as low
as the bottom edge of these said stops. Connected with each of these
trunks, at the bows, there is an upright trunk reaching above the londwater
line of the craft or vessel. These upright trunks are covered at the top with
a plate having openings for the admission of air into them, and also a passage

page_text: for its escape into a blow-off trunk on its having expelled the water. Above
this plate is a sliding valve, similar to the D valve of the steam engine, to
admit the compressed air into either of the trunks, and also to allow its escape.
Above this valve I place an air-vessel which forms the valve box, and into which
compressed air is to be forced by air-pumps worked by steam or other power, as
described for No. 1, of capacity proportioned to the size of the vessel or speed
required. The before-mentioned slide valve is to be connected with and
moved by the steam engine, with a ready means of adjusting the time of its
making its alternations, so that it may be moved either faster or slower than
the steam engine, according to the size of the pumps, power of engine, and
speed of vessel required. On the water being forced out by the compressed
air from one trunk, the slide valve will be moved by the steam engine shutting
off the compressed air, and allow the air contained in that trunk to escape
into the blow-off pipe, which trunk will be at the same time receiving water.
Whilst the air is forcing out the water in the before-mentioned trunks the
second trunk is discharging its air through the blow-off pipe, and receiving
water through the lower valve or trap in the end of the trunk, to be ready for
being emptied in its turn by the compressed air, so that the operation will be,
that whilst one trunk is being filled with water, the other will be being
emptied by the air being forced in alternately.
In the Drawing No. 2, Fig. 1 represents a general plan of this arrangement
of trunks, valves, &c., laying on the bottom of the vessel; Fig. 2, a longi-
tudinal section; Fig. 3, a transverse section of the same; Fig. 4, an enlarged
section of the trunks at the bows; Fig. 5, ditto at the stern; Fig. 6, an
enlarged section of vertical trunks. A, the upper trunk; B, the lower
trunk; C, D, the flap valves of the trunks; E, the upright trunks; F, the
slide valve and box; G, the air-pipe leading from the steam engine; H, the
air-vessel supplied with air from compressing air-pumps, as before described
for No. 1. I do not confine myself to any particular arrangement of the
details of this plan, but to the general principle of taking the water into the
trunks at the bows, preventing its return by the use of a flap-valve in the end
of the trunks, and expelling it at the stern by means of admitting alternately
into one trunk and then the other compressed air on the surface of the
water.
My Invention No. 3 consists in combining a Branca's rotary steam engine
with a propelling screw, which steam engine is worked by a small jot of high-
pressure steam issuing into a pipe of larger dimensions near to and leading
to the circumference of the wheel, to which the axis of the said larger pipe
forms a tangent. The nozle which delivers the before-mentioned jet of steam
terminates in a cavity or enlarged part of the pipe leading to the steam wheel.

page_text: where there is an opening admitting the atmospheric air, either cold or
heated, to rush into and mix with the steam, by which means a considerable
quantity of air is drawn in with the steam, producing a powerful effect on the
wheel, whereas the same quantity of steam alone would scarcely produce any
useful result. This steam wheel may generally be placed with its axis in the
same horizontal line as the axis of the screw, with an intermédiate shaft
between the engine and screw; avoiding the necessity of any secondary
machinery between the engine and screw for producing a greater velocity in
the screw than exists in the steam engine; but as the screw will by this
means be driven much faster than is usual by any of the ordinary means, the
diameter will be much less than any of those at present in use, compared to
the size of the vessel; and in consequence of the advantage and convenience
of having a small screw driven at a high velocity, it will in some cases be
found desirable to place the axis of the screw lower than may be convenient
for the axis of the steam engine, in which case I introduce a Hook's universal
joint at each end of the intermediate shaft of communication. In this part of
my Invention also I do not confine myself to any particular dimensions or pro-
portions of the several parts or details, nor to the manner of the introduction of
air with the steam, the whole of which may be varied and proportioned to the
size of the vessel, and to suit the particular cases to which it is to be applied.
In the Drawing No. 3, Fig. 1 represents a longitudinal elevation of the
engine, with the shaft of communication and screw; Fig. 2, a plan of the
same; Fig. 3, a front view of the engine or wheel, with the jets of steam and
currents of air, &c.; Figure 4, a longitudinal section of the engine through the
axis. A, the steam wheel, having six blades or floats, though the number
will be dependent on the size of the wheel at the vessel, screw, &c.; B, the in-
termediate shaft; C, C, the universal joints; D, the screw; E, the steam pipe
from the boiler; F, the jet nozle for driving the wheel in the direction of the
arrow G, or producing a forward motion of the vessel; H, the opening for
the admission of air; I, I, steain pipe; J, a three-way cock for admitting
steam to either of the angles or shutting off from the engine; K, a steam jet
and air entrance, as above, for driving the wheel in the direction of the
arrow L, to cause a backing motion of the vessel; and M, a pipe for
conveying away the steam from the engine in any convenient direction.
Having described the several parts of my Invention, I confine my claims of
originality in the separate improvements as follows:-
First, in No. 1, to using compressed air in the way herein described as a
means of propelling vessels.
In No. 2 I limit my claim to the use of compressed air admitted alternately
on the surface of the water contained in trunks, as described.

page_text: And, in improvement No. 3, I confine my claim to the combination of a
screw propeller, intermediate shaft, universal joints, and rotary engine as a
means of propelling; but I do not claim as my Invention the admission of air
with steam or any of the parts separately, as herein described.
In witness whereof, I, the said James Hamer, have hereunto set my
hand and seal, this Nineteenth day of July, One thousand eight hundred
and forty throa