A NEW OR IMPROVED MOTIVE POWER ENGINE
Year: 1857

page_text: LETTERS PATENT to Johan Ernst Fridrich Luedeke, of Birmingham, in
the County of Warwick, Mechanical Engineer, for the Invention of
"A NEW OR IMPROVED MOTIVE POWER ENGINE
"
Sealed the 5th February 1858, and dated the 28th October 1857.
PROVISIONAL SPECIFICATION left by the said Johan Ernst Fridrich
Luedeke at the Office of the Commissioners of Patents, with his Petition,
on the 28th October 1857.
I, JOHAN ERNST FRIDRICH LUEDEKE, of Birmingham, in the County of
Warwick, Mechanical Engineer, do hereby declare the nature of the Inven-
tion for "A NEW OR IMPROVED MOTIVE POWER ENGINE," to be as follows:-
My said Invention consists of a motive power engine constructed in the
following manner:-A hollow cylinder or drum containing air is mounted
upon a horizontal axis, and placed in an outer case filled with wäter or other
liquid. The axis of the drum passes to the outside of the said case. There
is an opening in the drum situated on its cylindrical surface. This opening is
provided with a lid or piston connected with the drum by a water-tight flexible
material, which permits of the piston rising or falling as the air in the drum
expands or contracts. When the drum is so situated that the opening is at

page_text: the lowest point, the piston is forced down by the pressure of the water, but
as by the turning of the drum the opening in the drum rises, there is less
pressure of water upon it, and the air in the drum expands, forces out the
piston, and the drum becomes buoyant on that side. The drum continues to
turn until it has performed a semi-rotation, when the side containing the piston
is at the top. In order to carry round the drum through the other half
rotation, the piston requires to be pressed so as to condense the air in the
drum. This is effected by pressure upon the liquid in the case. containing
the drum. To produce this pressure a cylinder containing water or liquid is
connected with the outer case, and a piston is placed on the top of the liquid
in the said cylinder. The said piston is pressed down by a weight fixed on an
arm which stands vertically in the first instance, and descends into a horizontal
position, so as to compress to the requisite degree the air in the drum while it
makes its second semi-rotation. As the drum is making the last described
motion, the piston in the water cylinder and the arm pressing upon it are
raised by the method hereafter described. When the opening in the drum is
at its lowest point, all pressure is removed from the liquid in the case, and the
air within gradually expands, and the side containing the opening having
become again buoyant, the drum performs spontaneously another half rotation.
Two of the apparatus described are mounted upon the same axis, so that the
opening in one is performing an ascending, while that in the other is perform-
ing its descending motion. The raising of the piston and weight of the water
cylinder is effected by a double excentric on the main shaft acting through a
lever on the said piston and weight. The weighted lever acts upon the water
piston by means of a toothed quadrant on the former engaging with a rack
on the piston rod.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Johan Ernst Fridrich Luedeke in the Great Seal Patent
Office on the 24th April 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHAN
ERNST FRIDRICH; LUEDEKE, of Birmingham, in the County of Warwick,
Mechanical Engineer; send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing: date the Twenty-eighth day of October, in the year of our
Lord One thousand eight hundred and fifty-seven, in the twenty-first year of

page_text: Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Johan Ernst Fridrich Luedeke; Her special licence that I, the
said Johan Ernst Fridrich Lúedeke, my executors,, adininistrators, and
assigns, or such others as I, the said Johan Ernst Fridrich Luedeke, 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 "A NEW OR IMPROVED MOTIVE
POWER ENGINE," upon the condition (amongst others) that I, the said Johan
Ernst Fridrich Luedeke, my executors or administrators, by an instrument 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 immediately
after the date of the said Letters Patent.
.
NOW KNOW YE, that I, the said Johan Ernst Fridrich Luedeke, do
hereby declare the nature of the said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained in
and by the following statement thereof, that is to say:―
My Invention consists of a motive power engine constructed in the manner
herein-after described, and illustrated in the accompanying Drawing. It will
facilitate the comprehension of the general principle of my Invention, if I
here state that it consists of a vessel immersed in water, one of the sides of
the said vessel being provided with a piston or with flexible material, or other-
wise constructed so that when depressed in the water the air in the said vessel
may be compressed into a continually diminishing space by the increasing
pressure of the water. The said vessel may be either made to move in the
water by being mounted upon an axis, or the said vessel may rise and fall in
the water by a vertical motion. I prefer the latter method of carrying my
Invention into effect, and shall limit my explanation thereto.
Figure 1 of the accompanying Drawing represents in vertical section a
large square case or cistern; this cistern is filled with water nearly to the top,
and a small cubical box marked a, b, c, d, is placed in the water in the cistern.
For convenience of description I will entirely disregard the weight of the
box a, b, c, d. If the interior of the said box were filled with water, it would
be in equilibrium, but when it is filled with air, as represented, weights must
be attached, in order to restore the equilibrium, the weight required for that

page_text: purpose being equal to the difference between the weight of the enclosed air
and the column of water displaced by the said air.
The case. or box a, b, c, d, is represented in Figure 1 in equilibrium, its.
upper surface a, b, coinciding with the level of the water in which the box is
placed. In the bottom c, d, is an opening f, and in the side b, d, a flap or
valve e, opening inwards. In the interior of the box is a piston h, k, l, which
is capable of motion in a horizontal direction from its position on the right of
the box, as represented, towards the left side a, c, of the box. The said piston
h, k, l, is connected with the box by means of a flexible material or otherwise,
so as to move without permitting air or water to escape between it and the
sides of the box. At g, is an opening in the piston, which may be closed as
required by means of a slide. The narrow space between the piston h, k, l, and
the side b, d, of the box is filled with water, and if the said space enlarge by
the motion of the piston, water can readily enter the said space through the
openings e, f. If the box a, b, c, d, be loaded with a small weight it would
sink in the water, and would raise the weight p connected therewith, as repre-
sented. During the sinking of the box a, b, c, d, the piston h, k, l, and the
air enclosed in the box will be subjected to a pressure equal to the weight of a
column of water, which has for its base the area k, and whose height is equal
to the height of the level of the water; above the middle of the areak the pres-
sure on different parts of k is of course different, owing to the different distances
of the several parts of k below the level of the water, but the total effect will
be equal to the pressure of a column on every part of k, which column has a
height equal to the distance of the middle of k from the level of the water.
As the box a, b, c, d, sinks, the pressure on the piston h, k, l, increases, and the
said piston is forced more and more to the left, the air within the box being
compressed with a continually increasing force.. At the same time the weights
attached for the purpose of bringing the box a, b, c, d, into equilibrium will
become a constantly increasing overweight or excess, and will carry the box
down with an increasing velocity. This accelerated motion may be converted
into a uniform one by the balance weight p being suspended upon a fusee, as
represented, or by otherwise suspending the said weight p, so that as it rises its
resistance shall increase in the same ratio as that in which the weight of the box
a, b, c, d, increases in sinking. A uniform motion in the descending box may
also be produced by the means illustrated in Figure 2; in the said Figure 2
the box a, b, c, d, is open at bottom, but closed on its other sides, the said box
being supposed to be in equilibrium, a small weight placed upon it will cause it
to sink in the manner described with respect to Figure 1. The enclosed air

page_text: being subjected to a pressure equal to the distance of the surface of the water
inside the box a, b, c, d, and that of the water external to the box a, b, c, d,
the pressure to which the air in the box a, b, c, d, is subjected.consequently
increases as the said box sinks and the volume of the air diminishes, and the
weight required to bring the box in equilibrium when the said box was at the
top of the water will be in excess when the box sinks, and the motion of the
said box in its descent will be consequently an accelerating one. In order to
make the motion of the box a, b, c, d, uniform, I resort to means whereby the
volume of the air in the box, although compressed, does not change its level
in the said box. This is effected by means of the pillar s fixed on the bottom
of the cistern; the said pillar s enters the box a, b, c, d, while the said box-is
sinking, and occupies a space therein equal to the space by which the volume
of air has been diminished. The level of the water in the interior of the
box a, b, c, d, being maintained at the same height above the open mouth of
the box, the said box descends with a uniform motion. I will next describe
what will happen when the box a, b, c, d, has sunk to the greatest depth,
as represented in Figure 3. The apparatus is precisely similar to that repre
sented in Figure 1, excepting that the air enclosed in a, b, c, d, is put
into connection with the interior of the box A by means of a pipe made
of india-rubber, opening into the side a, c. The box A is filled with
air; no essential change is caused by this circumstance, yet now a larger
mass of air sustains the pressure acting on the piston h, k, l, by which it is
evident great facility of moving the piston will be obtained. The size of the
box A must be such that at the moment when the box a, b, c, d, has reached
its deepest position the piston h, k, l, arrives at the side a, c, as is shown in
Figure 3. The advantage of this great facility of moving is as follows:-
Whilst in the position represented in Figure 1 the entire inner space of
a, b, c, d, was filled with air, it is now almost entirely filled with water, that is,
the entire space on the right from the piston; hence the highest increase of
weight of the apparatus which has sunk down is effected. I have already
shown that this increase of weight is compensated by the mode of suspending
the weight p (see Figure 1), so that the box a, b, c, d, in its actual position
does not exercise a greater draught downwards than in the first moment of
its sinking.
It may appear absurd to consider such a highest possible increase of weight
as desirable, which in fact (at least up to this point) has been without effect.
It will be seen that it will have a considerable effect in a negative manner.
I have already remarked that the different points of the piston h, k, l, are to

page_text: bear a very different pressure of the water, yet the compressed air beyond the
piston and in the box A only sustains the total effect of that pressure, varying
as it does in the different heights of the surface of the piston; it has of course
the same tension above and below. Now it is true that this tension entirely
counterpoises the total pressure of the water acting on the right side of the
piston, and that the piston is in repose, but this equilibrium does not occur on
all points of the piston at different heights.
The pressure of the water being least above and greatest below, whilst the
pressure of the air on the other side is the same everywhere, it seems
impossible that an equality of pressure from both sides should take place on
the whole of the surface of the piston. An opening applied below would
admit water into the space of air, whilst from an opening above air would
be introduced into the space of water; no escape would be effected in the
middle by an opening. The Drawing represents the piston opened at g; this
movement of the piston may be regulated by the engine itself whenever it is
desirable. As I have above explained, air must penetrate into the space x,
filled till then with water, and depress the water (yet not so far as half the
height of a, b, c, d,); the flap e will shut freely, and the water can recede
through the opening f. It will now be clear for what reason the greatest
possible although not effective increase of weight is desirable, for now the
diminution of weight effected by the re-entrance of air becomes the more
considerable. If, as I said before, there takes place equilibrium, or rather only
a slight overweight, it is evident that this is not only overcome now, but still by
a corresponding diminution of the weight p (the weight taken away represents
the result of the engine) the box a, b, c, d, will return upwards into its original
position, the water will again and entirely recede from the space a, b, c, d,
(Figure 1), and a function of the engine may now draw the piston to the
right without a perceptible employment of force; hereupon the first movement
downwards repeats itself and raises a second weight p to the same height.
By attaching a rod to the top of the box a, b, c, d, in the several Figures, the
rising and falling motion of the said box may be communicated through the
said rod to a crank, or the said motion may be transmitted in any convenient
manner to any machine which it may be wished to actuate.
Having now described the nature of my said Invention, and the manner of
carrying the same into effect, I wish it to be understood that I do not limit
myself to the precise details herein described, and illustrated in the accom-
panying Drawing, as the same may be varied without departing from the
nature of my said Invention; but I claim as my Invention the new or

page_text: improved motive power engine herein described, and illustrated in the accom-
panying Drawing, that is to say, a motive power engine in which the motive
power is obtained by the motion of a vessel in a cistern or reservoir of water
or other liquid in the manner described and represented.
In witness whereof, I, the said Johan Ernst Fridrich Luedeke, have
hereunto set my hand and seal, this Twenty-third day of April, in the
year of our Lord One thousand eight hundred and fifty-eight.
Witness,
GEORGE SHAW.
JOHAN ERNST FRIDRICH LUEDEKE. (L.S.)