A NEW MOTIVE-POWER ENGINE
Year: 1865

page_text: LETTERS PATENT to Herman Leonhardt, of St. Gall, in the Republic
of Switzerland, for the Invention of "A NEW MOTIVE-POWER ENGINE."
PROVISIONAL SPECIFICATION left by the said Herman Leonhardt at the
Office of the Commissioners of Patents, with his Petition, on the 12th
April 1865.
I, HERMAN LEONHARDT, of St. Gall, in the Republic of Switzerland, do
hereby declare the nature of the said Invention for "A NEW MOTIVE-POWER
ENGINE," to be as follows:-
In carrying out my Invention I avail myself of the property of bodies or
objects of a certain specific gravity when immersed in a fluid of a greater
specific gravity to rise or ascend to the surface of such fluid. This buoyancy
represents a greater or a lesser force or power according to the greater or
lesser difference between the specific gravity of the object and that of the
fluid, and the size of or the displacement caused in the fluid by such object.
In order to make the said objects which I will call floats as light as possible,
and yet strong enough to resist the pressure of the water, I construct them of
thin sheet metal, and in preference in the form of tubes or hollow cylinders
with flat ends. A number or series of these cylinders placed horizontally
parallel to each other are hinged or linked together in a similar manner as

page_text: the buckets of a chain pump; this chain of floats is passed over two sets of
pulleys or discs fixed to two horizontal shafts, the one placed vertically above
the other, the said pulleys being formed to suit the diameter of the floats.
One half of this chain of floats passes through the centre of the tank holding
the water or other fluid, and the other half passes outside the tank through
the air. The floats when in motion enter through the bottom of the tank, in
the manner hereafter described, and rise up by their buoyancy through the
water; they then pass round the top pulley, descend outside the tank, and
passing over the bottom pulley, again enter the tank, and so on. If cylin-
drical floats are used, as described, they are fixed on the connecting links half
a diameter or more apart from each other; therefore supposing the floats to
be 50 centimetres in diameter they would be placed 25 centimetres apart.
Now the principal part of my Invention consists in relieving the floats
when entering through the bottom of the tank of the pressure of the water
column, which pressure if not removed or neutralized would render the rising
of the, floats in the water impossible, and prevent the machine from acting.
The manner in which the floats are relieved from the pressure of the water
column when entering the tank is as follows:-On the bottom of the tank I
form an entrance chamber for the said floats of a depth equal to the diameter
of a float; the bottom of the chamber and its top are each provided with
double slides which open and close as the floats enter and leave the chamber.
Supposing the floats to be in motion, and one of them to have arrived in the
centre of the chamber, a lever actuated by the moving floats or by the
revolving float pulley or disc will cause the top or egress slides of the chamber
to open in the same measure as the float rises; this slide acting through
another lever will at the same time open a slide or valve in the side of the
chamber and admit water into it, thereby bringing the water in the tank and
in the chamber into equilibrium. When one half of the float has passed
through the top or egress slide the next float will have arrived at the bottom
or ingress slide, which latter will now open in proportion to the rise of the
float. The egress slide will close in the same measure and at the same time
shut off the communication between the tank and the chamber which was
necessary for establishing the equilibrium. At this juncture other valves con-
necting the chamber with pipes leading to the top of the tank are opened, and
the water in the chamber which would be detrimental to the further rise of
the entering float is withdrawn through these pipes, which I will call return
pipes, by suction, and allowed to flow back into the tank above the water
level; this suction is effected through the following arrangement :-That
portion of the top of the tank where the floats leave the water is open, but

page_text: as the
the other portion of it is covered, and a partition dividing it from the open
portion is made to dip into the water to some depth, thereby rendering it a
hermetically closed chamber, and the above-mentioned return pipes open at a
certain height above the water line into it. This chamber I call the vacuum
chamber, because previous to starting the machine a vacuum or a partial
vacuum must be formed in it, and afterwards maintained as long
machine is to continue in operation. The air is exhausted from the chamber
by means of an air pump driven by the machine, but arranged for driving by
hand for the purpose of starting the machine. By forming this vacuum the
original water level in the tank will be disturbed, the water level being
raised in the vacuum chamber and lowered to a corresponding extent in the
open part of the tank. Supposing the tank to be of a height to hold six floats
1, 2, 3, 4, 5, & 6, 1 being the one above described, as entering the admission
chamber, it is clear that as 6 leaves the water the water level in the open
part of the tank will be lowered in proportion to the displacement previously
caused by 6, and the water level in the vacuum chamber being thereby like-
wise lowered, it will cause a suction or drawing up of water in the return
pipes, equal in quantity to the amount of water displaced in the entrance
chamber by the entering float 1. The water sucked up through the return
pipes will flow over into the vacuum chamber and distribute itself in the
water of the tank. The ingress and egress slides of the entrance chamber
are furnished with linings or packing of felt previously boiled in oil for
ensuring a water-tight fit against the floats without much friction, and the
flat ends of the floats likewise pass between sheets of felt previously boiled in
oil and pressed against the flat ends by fluted rollers. The air pump is main-
tained in operation in order to remove the trifling quantity of atmospheric air
adhering to and introduced into the tank by the entering floats. The motion
communicated by the rising floats to the float pulleys or discs and shafts is
further transmitted by means of belts or other gearing in the manner usual
with other motive-power engines.
The details of arrangement and construction of my new motive-power
engine may be altered or varied, but the main feature of my Invention
consists in relieving the floats, when entering the tauk, of the pressure of the
water column by means of a vacuum chamber and parts connected therewith,
as described, or their equivalents.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Harman Leonhardt in the Great Seal Patent Office on the
12th October 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HERMAN
LEONHARDT, of St. Gall, in the Republic of Switzerland, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twelfth day of April, in the year of our Lord
One thousand eight hundred and sixty-five, in the twenty-eighth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Herman Leonhardt, Her special licence that I, the said
Herman Leonhardt, my executors, administrators, and assigns, or such others
as I, the said Herman Leonhardt, 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 MOTIVE-POWER ENGINE," upon the condition (amongst others) that
I, the said Herman Leonhardt, my executors or administrators, by an in-
strument 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 Herman Leonhardt, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
The action of my new motive-power engine is based upon the property of
solids, or bodies of a certain specific gravity when immersed in a fluid of
greater specific gravity to rise or ascend to the surface of such fluid. This
buoyancy represents a greater or lesser force or power according to the greater
or lesser difference between the specific gravities of the body and that of the
fluid, and the size of or the displacement caused in the fluid by such body.
In carrying out my Invention I use a number of such bodies, which I will
call floats, and which I prefer to construct in the form of cylinders with flat
ends. These floats placed horizontally and parallel to each other, are
hinged or linked together so as to form an endless chain. This chain
of floats is suspended over two sets of pulleys or discs fixed upon two

page_text: horizontal shafts placed in the same vertical plane, the one above and the
other below the tank for holding the water or other fluid. The said
pulleys or discs are shaped to fit the floats. One half of the chain of
floats passes through the centre of the tank holding the water, and the
other half passes outside the tank through the air. As the weight of the
floats and connecting links on the one side of the pulleys is exactly balanced
by the weight of the floats and links on the other side, it is evident that
in this case neither the specific gravity nor the weight of the floats enter
into the calculation of the power of the machine, which is simply determined
by the displacement caused in the fluid. The floats might therefore be formed
of solid iron cylinders; but in order to prevent unnecessary weight and con-
sequent wear and tear, I prefer to make them as light as is consistent with
the necessary strength and solidity of the chain, and 1 construct them of thin
sheet metal formed into tubes or hollow cylinders with flat ends. The floats
when in motion enter through the bottom of the tank, in the manner to be
herein after described, and rise up by their buoyancy through the water, they
then pass over the top pulley, descend outside the tank, and passing over the
bottom pulley again enter the tank, and so on. In order, however, to render
this motion possible, it is absolutely necessary to relieve the entering floats
from the pressure of the water column; and this is effected by means of an
entrance chamber formed on the bottom of the tank, which is fitted with
ingress and egress slides for the floats, and also with certain valves in con-
nection with other parts, by means of which the communication with the
water in the tank is cut off and again re-established, and the water pressure
neutralised, when required, through the action of a vacuum chamber.
In order that my Invention may be better understood and more readily
carried into effect, I will now proceed to describe the same with reference to
the accompanying three Sheets of Drawings, and the letters and figures
marked thereon; the same letters and figures denoting similar parts in the
several Drawings.
In Sheet I., Fig. 1 represents a transverse section of one of my motive-
power engines, of about one-horse power, on a scale of oue-tenth of the
natural size; and Fig. 2 is an end elevation of the same; Fig. 3, on Sheet II.,
represents a longitudinal section of the machine; Fig. 4 a horizontal section
of the same; and Fig. 5 a front elevation of part of the water tank with
valve and slide arrangements.
The water tank A, made of sheet iron, rests with its cast-iron bottom flanges
on the beams P, P¹, whose ends may be supported by masonry. The upper
beams P, P, erve likewise for supporting and steadying the machine, and

page_text: are supported by the walls of the building. Above and below the tank are
fixed the pedestals B, B1, B2, B3, in the bearings of which the shafts d, d', of
the discs or float pulleys f, f, f, f³, are supported. These pulleys are keyed
upon the shafts, so that the axis of the several floats C, C', &c. shall fall as
near as possible in a plane with the centre of the tank. The pulley or
wheel d², by which the power from the machine is communicated to the
machinery to be set in motion, may be keyed at one end of the shaft d', as
seen in Fig. 3. The floats are linked or hinged together at distances of half
the diameter of a float from each other, or, in this instance, at a distance of
25 centimetres; this distance may be niore than half the diameter of a float,
but it must not be less. The links D connecting the floats are flattened at
their ends, and rivetted to lugs, which are cast to the end plates of the floats,
but the link ends and lugs must be able to turn freely on the rivets. The
tank A is about 4 metres and 4 centimetres in height, 1 metre and 15
centimetres in width, and 1 metre and 45 centimetres in length, and it
contains, after deducting the space occupied by the 5 floats, about 5-8 cub.
imetres of water. In order to prevent the pressure of the water column upon
the entering floats, an admission chamber K is placed over the entrance
opening in the bottom of the tank, see Figs. 1, 3, & 5. The top of this
chamber is composed of two slides S, S', which open and close according to
the requirements of the floats as they leave the chamber. Similar slides S, S³,
are fitted in the bottom of the chamber K. These slides perform the same
motion as the slides S, S', but not at the same time, for whilst the slides S², S³,
are closed, or closing, the slides S- & S¹ open, and with them the slide or
valve S' in the side of the chamber, actuated by the levers H, H'. Through
the opening of the valve St, the water in the chamber is made to
communicate with the water in the tank A and the float C'; represented
in Fig. 1, as enclosed in the chamber K, as well as the floats C, C³,
C, & C, will rise until the float C arrives at the slides S, S³. At this
moment those slides begin to open according to the rapidity of the rise
of the entering float C, whilst the slides S, S', & S close in the same
measure, and shut off the water communication and pressure, which was
necessary before. Simultaneously with the closing of the slides S, S¹, S', the
slides S &S, see Fig. 5, will have been opened through the levers H, H¹, and
the water now in the chamber, which would obstruct the further entering of
the float C is caused to withdraw through the slides S³, S, and tubes R, R',
to the water level, in the vacuum chamber z, a¹, which are connected together
The air has to be exhausted
through the pipes y, y', y, y³, see Figs. 1 & 2.
from the two chambers a, a, by means of an air pump L, and pipes L',

page_text: previous to the starting of the machine; it is therefore desirable to arrange
the pump so as to permit of being worked by hand as well as by power.
When the air is exhausted from a & a¹, the atmospheric pressure will force
the water in the two tubes R, R', up to the height marked W, above the
real water level W, see Fig. 1. The entering of the float C into the admission
chamber K, necessitates the rising of the float C³, which in passing through
the air-tight packing in the top of the tank, withdraws the atmospheric pressure,
and allows the water level. W to fall in proportion to the displacement
previously caused in the tank by the cylinder C. After the float C has left
the air-tight packing, the atmospheric pressure upon the water level W, will
cause the valves v, v³, to close, whereupon the water will again rise in the
tubes R, R', and the slides S, S³, having closed behind the float C, the former
operation will repeat itself. Without this withdrawing of the pressure of the
water column upon the entering floats, and the withdrawing of water from the
admission chamber through the tubes R, R', to the water level, by means of
the vacuum chambers, the working of the machine would be an impossibility.
The form and shape as well as the size and the number of the floats is
immaterial, nor is it of any importance whether they enter the admission
chamber in a horizontal position, as represented in Figs. 1 & 2, or in a vertical
position. The opening and closing of the slides S², S³, is effected through studs
projecting from the float pulleys f,f', which, when the pulleys revolve, strike
against a catch on the slido S, and thereby withdraw the same.
In Sheet III., Fig. 6, represents the slides S & S³, in isometrical perspective,
and Figs. 7 & 8, the springs which are attached to the slides. A connecting
rod y, see Fig. 6, connects the slide S, with one end of the lever H, which
vibrates round the fulcrum a, and whose other end is connected through the
connecting rod g with the slide, S. When therefore the slide S is withdrawn
by the revolving of the float pulley, the slide S³ will withdraw in the opposite
direction, and the admission chamber will be opened. During this operation,
one half of the float C will have entered the chamber, and the slides will be
closed again by the next stud on the pulley acting upon the bell crank lever i.
In order to render the slides S, S³, water-tight, the sides or edges of the two slides
which meet when closed, are tapered off in curves corresponding more or less
with the shape of the floats; these tapered off edges have springs fixed to
them, see Fig. 6, which are covered with sheets of felt, previously boiled in
oil. These springs, see also Fig. 7, must be capable of opening out so as to
stand nearly vertical on the slides for the purpose of still pressing the felt
against the float when the slides are fully withdrawn. The springs attached
to the under side of the slides S & S³, see also Fig. 8, are not required to

page_text: open to the same extent, as those on the upper side, and they are rivetted to
the slides, whilst those on the upper side are hinged. The aperture formed
in the slides for the links of the float chains are likewise fitted with slides,
which as the large slides are withdrawn, are pressed forward by spiral springs,
see Fig. 6, and close the apertures to prevent escape of water. The construc-
tion can be varied and made for instance as in Fig. 4, at O & O¹, or in Fig. 6,
at 03 & 0³. The water-tight packing during the entering of the floats against
the two flat ends is effected by means of sheets of felt, likewise boiled in oil, and
situated at the sides of the chamber. These sheets of felt are pressed against
the flat ends of the floats by means of fluted rollers, see Figs. 1 and 3. The
opening and closing of the upper slides S & S¹, is effected by means of the
shears m, m³, see Figs. 1 & 3. These are actuated through the connecting
rods n & n', connected with the levers Z, which latter are alternately pressed
downwards and again raised studs fixed to the float pulleys f³, f. This
raising and lowering of the connecting rods may however instead of through
the shears act upon the slides through simple bell-crank levers. On the pulley
shaft d, Fig. 2, a crank is fixed outside the pedestal R, this crank actuates by
means of a connecting rod the air pump L, which serves to withdraw the
air, which enters by degrees with the water through the pipes R, R¹, into the
vacuum chambers a, a, and if the air is withdrawn in the same measure as
it enters, the water will by the action of the pump be maintained at nearly
the same level W', as may be seen on the water guage O. The pipes R, R',
may in this case be shortened a few inches, whereby a slight increase in the
power of the machine will be obtained. The adjustment of the quantity of
water accumulated in the chambers a, a, takes place during the passage of
the float C, through the air-tight packing A' in the mouth of the tank, when
the weight of the water in the chamber a, a¹, opens the valves v, v', and the
valves will be again closed through the atmospheric pressure, when the
cylinder C³ will have left the air-tight packing. The size of the valves v, vl,
is regulated by the bulk of water which has to pass through them. The cubic
contents of the two pipes R & R', are equal to half the cubic contents of one
of the floats. The cubic contents of each float are 0.2 cub. metre, and as
the power of each float is equal to the weight of the displaced water, and as
1000 cub. centimetres of water weigh 1 kilogramme, it follows that each float
has a lifting power of 200 kilogrammes, and therefore 5 floats a power of
1000 kilogrammes with a velocity of 10 centimeters per second. Allowing
25 per cent. of this force for friction, for working the air-pump, and for re-
placing waste of water, there remains an available effective power of 750
kilogrammes at 10 centimeters per second, which is equal to one horse power.

page_text: Instead of forming the floats into a chain as described, they may be formed
into a circle by being secured at both ends to two hoops made of plate iron.
One part of this circle of floats would pass through the water tank, in a similar
manner as the chain, and the hoops would be supported and guided outside
the tank and in the tank by friction pulleys. Motion might in this case be
communicated from the motor through a pulley on the friction pulley shaft;
but I prefer the use of the chain as requiring less space, and giving more
power with a given number of floats.
Having now described the nature of my said Invention, and the manner in
which it may be carried into effect, I wish it to be understood that I do not
confine or restrict myself to the details and mechanical arrangements described
and shown in the Drawings, but what I do claim as the Invention to be secured
to me by the hercin-before in part recited Letters Patent is,
Firstly, the construction, general arrangement, and combination of motive-
power engines, in the manner and for the purposes substantially as described,
and their equivalents.
Secondly, the application of an admission chamber for the floats, with ingress
and egress slides, and with slide or valve arrangements for communicating
with the body of the water at the foot of the tank, and also through a tube or
tubes with the water level at the top of the tank in the manner and for the
purposes substantially as described.
Thirdly, the application of a vacuum chamber or chambers connected by
means of valves with the head of the water in the tank, and also through a
tube or tubes with the admission chamber in the manner and for the purposes
substantially as described.
Fourthly, the application of an air or exhaust pump for the purpose substan-
tially as described.
Fifthly, the application of packing to the egress opening of the tank, so as
to form an air-tight fit with the floats passing through it substantially as
described.
In witness whereof, I, the said Herman Leonhardt, have hereunto set
my hand and seal, this Sixth day of October, in the year of our
Lord, One thousand eight hundred and sixty-five.
HERMAN LEONHARDT. (L.S.)