A METHOD OF COMMUNICATION OR MEANS OF INTERCOURSE BY WHICH PERSONS MAY BE CONVEYED, GOODS TRANSPORTED, OR INTELLIGENCE COMMUNICATED FROM ONE PLACE TO ANOTHER WITH GREATER EXPEDITION THAN BY MEANS OF STEAM CARRIAGES, STEAM OR OTHER VESSELS, OR CARRIAGES DRAWN BY ANIMALS
Year: 1824

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
VALLANCE, of Brighton, in the County of Sussex, Esquire, send greeting.
WHEREAS His most Excellent Majesty King George the Fourth did, by
His Letters Patent under the Great Seal of the United Kingdom, bearing
date at Westminster, the Nineteenth day of February, in the year of our
Lord One thousand eight hundred and twenty-four, in the fifth year of His
Majesty's reign, give and grant unto me, the said John Vallance, my exors,
adiñiors, and assigns, His especial licence, full power, sole privilege and
authority, that I, the said John Vallance, my exors, adññiors, and assigns,
during the term of years therein mentioned, should and lawfully might make,
use, exercise, and vend, within England, Wales, and the Town of Berwick-
upon-Tweed, and also in all His Majesty's Colonies and Plantations abroad,
my Invention of "A METHOD OF COMMUNICATION OR MEANS OF INTERCOURSE
BY WHICH PERSONS MAY BE CONVEYED, GOODS TRANSPORTED, OR INTELLIGENCE
COMMUNICATED FROM ONE PLACE TO ANOTHER WITH GREATER EXPEDITION THAN BY
MEANS OF STEAM CARRIAGES, STEAM OR OTHER VESSELS, OR CARRIAGES DRAWN
BY ANIMALS;" in which said Letters Patent there is contained a proviso that
if I, the said John Vallance, shall not particularly describe and ascertain the
nature of my said Invention, and in what manner the same is to be performed,
by an instrument in writing under my hand and seal, and cause the same to
be inrolled in His Majesty's High Court of Chancery within six calendar
months next and immediately after the date of the said Letters Patent, that

page_text: then the said Letters Patent, and all liberties and advantages whatsoever
thereby granted, shall utterly cease, determine, and become void, as in and
by the same, relation being thereunto had, will more fully and at large
appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
John Vallance, do hereby declare that the nature of my said Invention, and
the manner in which the same is to be performed, are particularly described
and ascertained in and by the Drawings hereunto annexed, and the following
description thereof (that is to say):
The means of intercourse (the word means being used by me in the
plural number) which I have invented, consist, firstly, in a combination of
apparatus (to the invention of or exclusive right to the seperate parts of which
I make no claim, except as herein-after excepted), by the operation of which
air may be caused to convey persons or transport goods from one place
to another with greater expedition than by means of steam carriages, steam
or other vessels, or carriages drawn by animals; and, secondly, in another com-
bination of apparatus (to the invention of or exclusive right to the seperate
parts whereof I make no claim), by the operation of which water may be
caused to communicate intelligence from one place to another with greater
expedition than by means of steam carriages, steam or other vessels, or car-
riages drawn by animals.
The first of these means is put in practice in the following manner :-
Between the places from and to which intercourse is to be effected I extend
a hollow tube of any shape that may be convenient, and composed of any
material that will answer the purpose. As, however, that shape and that
material are best in point of effect, I shall here refer to a cylinder as the
shape of the tube, and to cast iron as the material of which it is composed,
though I vary both the shape and the material whenever circumstances may
render it desirable so to do. This cylinder reaches from one to the other of
the places between which intercourse is to be effected. It may be of any
size that may be desired, provided that desired size is not larger than they
can be cast. In the present instance it will be considered as six feet in
diameter. It is constructed in the following manner :-Cylindrical pieces,
each as long as they can be cast (suppose twelve feet), by the required
diameter (suppose six feet), and about an inch and a quarter in thickness, are
cast and bored so as for the inside of them to be truly cylindrical, except just
at the ends, where they are to be most slightly conical for about three inches
from each end. These cylindrical pieces are to be about a quarter of an inch
thicker at the ends (on the outside) than elsewhere, as is meant to be shewn

page_text: by Figure Eleven, B, so as to admit of about three inches of their length on
the outside at each end being turned (or in any other convenient way), ren-
dered of exactly the same size and circumference, and caused to have a fair
and smooth surface. The inside is also to be bored rather larger at the ends
for about three inches in, so as to be nearly an eighth of an inch larger at the
very end than elsewhere, and from the end this increase is to be diminished
or bevilled off so as to render the bore most slightly conical for about three
inches in. The ends themselves are to be faced or squared off, so that they
may be of exactly the same length in all parts. These cylindrical pieces are,
in any convenient way, to be laid along the ground from one to the other
of the places between which communication is intended to be made, so as
to form one long cylinder, that is, they may be put on low walls running
the same way as the cylinder, and three or four feet part, or in any way
that may be convenient, and will cause them to bed or lay firmly, and
so as to accord with the course of the ground. These cylindrical pieces
being all rendered exactly the same size at the ends (on the outside) are to be
connected together so as to form one long cylinder in the following manner :-
They are so laid and bedded on whatever it may be they are supported by as
for their centres to be exactly in the same line, which will bring the turned
part of their ends in such a position as will admit of a hoop being put round
them in order to make a joint. Thus each piece being brought to 'within
nearly a quarter of an inch of the one it is to be connected to (not closer, to
leave room for expansion), and there fixed or bedded so as for its end to
correspond exactly with that one, a piece of thick flannel about six inches
wide, by the necessary length, which has been previously well soaked in
melted tallow, is wrapped three or four times round the ends of each of those
cylindrical pieces on the parts that have been turned so as to be smooth and
exactly of the same circumference. Over the flannel is then placed a hoop
of the same width made of wrought iron about a quarter of an inch thick.
This hoop is in two pieces, each half the circumference of the cylinder,
connected by a strong hinge joint, and with a powerful nut and screw at the
other ends, so as to admit of its being drawn very tight, in order to press the
greasy flannel close to the iron, and make a tight-joint. When this hoop is got
into the proper position. so as for it to have an equal bearing on both the
cylindrical pieces it is intended to connect, the screw is turned so as to draw
it very tight, and cause it to press the greasy flannel very closely to the iron
beneath; and if the ends of the cylinders have been brought properly together
so as to admit of the hoops taking a fair and equal bearing on each, and the
flannel well soaked with tallow, and put round the ends, a joint will be made

page_text: that will admit of air being exhausted from these cylinders to a degree that
would lower a barometer inside them several inches without leaking; and
more than this, or a closer approximation to a vacuum, may not be necessary.
As these cylindrical pieces are thus put together to form one long cylinder,
there is to be fixed to the bottom of them, on the inside, a piece of iron cast
similar to Figures First of the Drawings annexed, where A gives an end
view of it, while B shews the plan of it. This piece of cast iron is to form a
groove, or channel, or track, for a wheel to run in, something similar to those
of a railway. It is to be about three inches wide in the track, and the inside
of the track, at the end where the pieces come together, is to be rather wider,
or bevelled off to allow a wheel to pass from one to the other without striking
against the end. These pieces are to be fixed by bolts, or in any con-
venient manner, and are to run the whole length of each cylinderic piece.
Figure Second gives an end view of one of these cylinderical pieces bedded
on two walls as it is to stand. In this, or in any other way that may be
convenient, are these cylindrical pieces put together so as to form one long
continuous cylinder reaching from one to the other of the places between
which communication is to be made, care being taken in putting them together
that they are so bedded and fixed as to be concentric, and cause their inner
peripheries and the groove or channel on the bottom of the cylinder to cor-
respond, so as not to cause any impediment to the vehicle which is to move
inside these cylindrical pieces. Should brooks or rivers interpose their course,
the cylinder must be carried over them by bridges, the construction of which
need not be referred to here; and where the line of the cylinder must be
varied, so as to follow the rises, falls, or turnings of the ground, the variation
must commence at a distance from the point, so as to admit of its being
rendered gradual, by each cylindrical piece being slightly deflected from the
right line as it is laid. This deflection must be very gradual in each piece, so
as not to oppose any sharp angles to the progress of the vehicle which is to
run inside; and the joints by which those cylindrical pieces are united must be
varied by having a double or triple thickness of flannel round them, in order
that there may be enough for the hoop to press into to make a tight joint.
Care must also be taken that the whole of these thicknesses of flannel are so
soaked in tallow (warmed to render it liquid) as completely to fill the pores of
it, or the joint will not be tight.
Procedure being thus made with the cylinder or vehicle to move inside it is
prepared thus-A frame of timber is formed in the following manner :-
A and B, Figure Third, are two pieces of timber, each about twelve feet long
by six inches wide and two thick, and C & D are pieces about four feet long

page_text: by six inches wide by two thick. These pieces C and D are morticed or in
any convenient way connected to the others, as shewn by the Drawing, so as
to leave a space of a foot between them (C and D), as shewn in the Figure.
A similar frame to this is now prepared. These two frames are laid one
on the other, and bolted or in any convenient way strongly fixed together,
with a space of four inches between them. Into this space, at cach
end of the pieces A and B, are now (or at the time of fixing the two
frames together) put pieces of cast iron similar to X, Figure Fourth.
These pieces are to be strongly connected to A and B. Z, Figure Fourth,
gives an edge view of X. Figure Fifth gives an edge view of the two
frames, shewing the pieces X between them. Between these two frames
is now to be put a wheel for them to run on, as shewn by Figure Sixth.
With reference to this wheel there are, however, some preliminary observations
to be made. The word wheel, when applied to vehicle's, is generally used in
the plural number. With reference to this vehicle, however, it is otherwise,
as, in order to diminish friction and admit of the vehicle's being more easily
moved, and that it may be better adapted to variations from the right line, it
is carried by or on one wheel. There are, to be sure, several small wheels
or rollers made use of to keep the vehicle upright, but it runs on and is
carried by one wheel. The rate also at which this vehicle is to move is
beyond the common, and every one knows that a carriage in rapid motion
very much shakes and jars what it passes over. Now, with a tube composed
of certain materials, this concussion might be attended with injurious effects;:
in order, therefore, to prevent this shaking from being injurious to the cylinder;
I soften it in the way stated with reference to this sixth Figure. In it
A, B, C, and D, form one side of the vehicle. E is a cylinder of gun metal,
about half an inch thick. It is about a foot long by nearly a foot in.
diameter, so that it has an area of one hundred square inches. It is open at
bottom. The top is an inch thick, so as to bear great pressure. This cylinder
is in any convenient way fixed firmly to A, C, and D, so as for it to be as shewn
by the two circles E and E in Figure Fifth. This cylinder is bored and fitted
with a piston, so as to be air-tight. S is the rod of this piston, which has at
bottom a hole (or link) for the axis of the wheel to go into. There are two
of these cylinders, one on each side, as shewn by Figure Fifth, and the axis.
of the wheel is attached to these pistons, as shewn in Figure Sixth. F is a.
piece of cast iron, of which Figure Seventh gives an edge view. It is finished.
so as to slide up and down between C and D, and with a hole in it for the
axis of the wheel to pass through. One of these pieces is put between C
and D in each frame. Attached to the vehicle, of which this frame forms part,

page_text: must be a condensing air pump, though, as its situation in the vehicle may be
varied according to convenience, it is not here shewn. To this pump is
attached a pipe, which will admit of air being forced into the cylinder E, so as
for two or more atmospheres to be forced into this cylinder between its end (or
top) and the piston. With things thus arranged, if this frame be raised so as
to stand perpendicular, it will be carried by the pistons and their rods s, since,
as the sliding piece F, to which the axis of the wheel is attached, moves up
and down as far as those rods will let it, the frame must be carried by them
and their pistons. Now, if under these circumstances the air pump be worked
so as to force air into the cylinder E, between the top of those cylinders and
their pistons, the pressure of that air acting upwards against the tops of the
cylinders, and downwards against the pistons, (which, by their connection to the
axis of the wheel, press upon or take their bearing from the ground), will raise
and bear up the cylinders and frame so as for it to be carried by an clastic
medium. Now, under these circumstances, we have an apparatus which not
only acts as springs to a coach, but also executes the purpose it is intended for
with a precision that no other method of obviating or diminishing concussion
will approach to. Since as air is one of the most elastic media we know of,
and as it requires but condensing to the proper degree to render the pressure
against the top of the cylinder so exactly the counterpoise of the weight of the
frame as to admit of its sinking and rising with a softness of vibration which,
(under a similar weight) coach springs can never approach to, it is but
increasing the condensation from ten to one hundred pounds an inch, to-render
springs which at one time are exactly adapted to a load of one ton in the next
minute adapted to a load of ten tons, and so on in greater or less proportion.
In this way I diminish concussion, let the vehicle be loaded as it may. The
wheel itself extends below the frame, that the frame may move clear of the
wheel track; this wheel may be of any size that is convenient. One way of
driving the air pump which forces condensed air into the cylinders E is to
connect it by some small wheels and machinery to the axis of the wheel by
which the vehicle is carried, as then the rotation of that wheel will keep the
pump constantly going, and if a safety valve, loaded to the degree of con-
densation required, be fixed on the top of the cylinder E, the condensation
within will be always kept exactly right. To this frame are now attached
circular ribs of elm or ash, about four inches wide by two thick, composed of
segmental pieces formed of two thicknesses glued and fixed together with the
grain crossing and strengthening each other, as is usual in forming large circles
of elm or ash. These circular ribs are to be nearly as large as the cylinder,
and are to be attached (as see Figure Eighth) to the top of A and bottom of B,

page_text: in any manner that will strongly connect them together. At the bottom of
them is to be a piece cut out similar to m, Figure 9, to allow them to pass over
the wheel track. They are put about twelve inches apart, lengthwise the
frame, excepting in the middle, where one is omitted to allow the wheel to run
in the track, vide Figure Eighth. Figure Ninth is meant to give an end
view of the frame, shewing one of these circular ribs. a, a, shewing the
rib; b, b, the two bottom pieces of timber; c, c, the two top pieces. When
the whole of these ribs are attached to A and B, they are boarded all
round on the inside so as to render them capable of holding goods like the
hold of a ship, the bottom pieces b, b, and the top pieces e, e, projecting from
the bottom and top like the keel and beams of a vessel. Figure Tenth
shews the door by which the ends of the vehicle are closed, that the air
may act against and drive it forward. It is of cast iron, and consists of a
rim d, d, four radii e, e, e, e, and a hollow diameter piece fon which it revolves.
This piece f has a hole through it lengthways for an axis to go through. The
ends of this axis fit into the holes shewn in the ends of Figure Fifth. The
spaces between the radii of Figure Tenth are filled with sheet iron, and when
this is done and it is put in its place at the ends of the vehicle, it turns on its
'axis and closes the end of the vehicle, (in the same way as the dampers fixed
in the cylinderic sheet iron flues of moveable fireplaces close the aperture
and stop the draught), excepting the crevice left all round between the outside
of it and the inside ribs or (rather) boarding; one of the end ribs is made as
nearly the size of the inside the cylinder as can be without touching it, suppose
one tenth of an inch smaller. To the two end or outside ribs, where the one
shewn (Figure Ninth) is marked < and > (to the sides, level with the centre
and to the top that is) are now fixed rollers or small wheels, the purpose of
which is to keep the vehicle perpendicular in the cylinder, by touching and
bearing against the top and side of the cylinder, as the vehicle may lean to
one or the other. With things thus arranged, if this vehicle is put inside the
cylinder with the wheel in the groove or track provided for it, the rollers
< and > fixed to it will keep it perpendicular so as to admit of its moving
forward, since as the side rollers < and >, and the corresponding ones at the
other end or rather on the other end rib, will prevent it inclining to either side,
and as the top roller V and the corresponding one on the other end rib will
prevent its inclining either forward or behind, the whole weight will be con-
centrated on the wheel. The vehicle is constructed in this way with only one
wheel, for the reasons that friction is diminished by the weight being thrown
on one axis, and in order that it may more easily adapt itself to and follow the
deflections from a rectilinear direction, which the nature of the ground may

page_text: render necessary in the course of the cylinder. Wherever it
may be 'desirable,
however, I make use of two wheels with reference to this vehicle, placing
them one at each end, as the wheels of the velocipedes were placed, that they
may both run in the same wheel track. In any convenient part of the inside
of the vehicle, and working on a bolt passing through the two top pieces c, c, is
fixed a lever (or if necessary two levers), the shorter end of which is fitted so
as to rise and rub against the top of the cylinder whenever the other end is
pressed down. This lever (or levers) is for the purpose of stopping the vehicle
by causing friction, as follows:-When it is wished to stop the vehicle, the
ends (Figure Tenth) are moved on their centres so as to place them at right
angles with the position in which they stand when they close the ends of the
vehicle, causing them to be with their edges in a line with the vehicle, which
has a similar effect to that of lowering the sails of a ship, as the air then
passes through the vehicle instead of acting against it; this is done some time
before it arrives where it is intended to stop, that its velocity may diminish
gradually, and when this opening the ends is not enough to stop it, the longer
end of this lever is caught hold of by the person directing the vehicle inside,
and his weight thrown upon it in a way which causes such friction between
the other end of it and the cylinder as soon to stop the vehicle. The inside
of the cylinder is marked or numbered with white paint at every mile, and
lights being carried in the vehicle it is known when to open the ends, &c., &c.
In loading the vehicle care must be taken to adjust the load so as for it to
balance on the wheel as near as may be that the friction may be concentrated
on the wheel. The construction of the vehicle being thus described, procedure
as to putting it in motion is made thus:-Adjoining and connected to the ends
of the cylinder, in each of the places to which it goes, are erected immensely
large air pumps, driven by steam engines of proportionate power. These
pumps are provided with two sets of valves, so arranged and connected to
them by pipes and cocks as to admit of their being rendered exhausting or
condensing pumps merely by shutting two cocks and opening two others.
These pumps are for the purpose of exhausting air from or forcing it into this
cylinder, as it may be intended to operate, by exhausting or condensing, or, in
other words, by a vacuum or a plenum. A particular description of these
pumps it is not necessary to give, since as the principle of the air pump
(whether for exhausting or condensing) is well known, stating the particulars
of their construction would but be troubling every engineer with a verbose
detail of what is already known to him; for this reason therefore, and as
cylinders and pistons as large as will be required for the object before
us are frequently fitted up in a way which, in fact, renders them con-

page_text: densing air pumps for blast furnaces, I decline burthening the subject with
detail which would to engineers be tedious. To each end of the cylinder
is fixed a kind of door for the purpose of closing the end and admitting
of a partial vacuum or a plenum being produced in the cylinder. These
doors are in fact valves, being so made as to act as such, as will be seen when
their construction is described. Now supposing these valves to be shut and
the pumps at one end of the cylinder set going, so as to exhaust air from
the cylinder, a portion of the air contained in the cylinder will be pumped out
of it. The density of the included air at the end whence it is taken will
consequently be diminished; and as, by the operation of its expansive prin-
ciple, this diminution will be felt at the other end of the cylinder, a pressure
proportioned to the quantity pumped out of or exhausted from the cylinder
will take place on the whole outer surface of the cylinder, and, consequently,
on the valves which close its ends; that is to say, supposing the exhausting
were to be to an extent which would cause a barometer inside the cylinder to
stand about two inches lower than one exposed to the open air stood at, a
pressure of about a pound per square inch would take place on the whole
outer surface of the cylinder, and, consequently, on the valves at each end.
Now, if instead of that end of the cylinder which is remote from the pumps
by which the exhausting has been effected being closed, as has been stated,
the vehicle just now described had been inside it, with its ends shut, so as to
prevent the passage of air through it, a pressure proportioned to the difference
between the air inside the cylinder and the atmosphere would have taken
place on the end of the vehicle. And supposing the diameter of the cylinder
to be six feet, and the pressure a pound per square inch, an impulse equal to
about four thousand pounds would have pressed against the end of the vehicle,
tending to force it toward the pumps. And supposing also that the pumps
were kept going, this vehicle would be driven toward them at the rate they
pumped the air out. Now, as the rate at which they do this will be in pro-
portion to the number and magnitude of them, and the rate at which they are
worked, it is but having them large and numerous enough, and working them
with the proper velocity, to cause the vehicle to move at any rate that may be
desired, not exceeding that at which air will rush into and along the cylinder.
Now as cylinders of from ten to twelve feet diameter are cast and bored and
fitted with pistons and valves for blast furnaces, it follows that they may be had
of the same size for the purpose of exhausting air from this cylinder, and as a
reverse arrangement of the valves will render then exhausting instead of
blowing machines, it is also, of course, that they may be caused to operate
as is necessary with reference to the object before us. Supposing, therefore,

page_text: that exhausting pumps of the diameter of twelve feet were made use of,
every foot which the pistons of those pumps moved would cause the vehicle to
receive an impulse tending to carry it nearly four feet forward, provided the
cylinder was everywhere tight and that no leakage took place by the vehicle,
two counteractives which we will for the present regard as inoperative. The
number of feet which the pistons of these pumps would move per minute
depends on the degree of exhausting and the power employed to work them.
Supposing, therefore, that the exhaustion should be to a degree which would
cause a barometer placed inside the cylinder to stand rather more than an
eighth of an inch lower than one exposed to the open air stood at (which
would give a pressure of about an ounce per square inch), and the piston of the
pump were moved at the rate of two hundred and twenty feet a minute, the
power required to work it would be about seven horses, and the effect
produced, (leaving friction and leakages out of the consideration), would be the
vehicle's moving forward about eight hundred and eighty feet, or at the rate
of ten miles an hour. In whatever proportion, therefore, it is intended the
velocity of the vehicle shall exceed ten miles an hour must the number of the
pumps and the proportion of the power by which they are driven be increased;
that is, if a speed of twenty miles an hour is intended, two pumps, and power
equal to about fourteen horses, must be had, and so on in proportion. By
arranging in this way, therefore, the rate at which the vehicle can be caused
to move may be regulated at pleasure, the power made use of to work the
pumps being increased to allow for their friction, as the quantum I have
specified relates only to the pressure on or against their pistons. Allowance
must also be made for leakages which may be unavoidable, by having an
extra pump or pumps and power, as practice may prove to be necessary.
Supposing these things to be done, and that the course of the cylinder was
level, the weight which might be moved in the vehicle or vehicles would be
very considerable; since as the wheel track or course would then be similar
to a railway, and as the average of many railways proves that any power
applied to a carriage on one will move above a hundred times as much as that
power at the same rate it moves at, it should seem that above eleven tons
might be moved in this way, as will be shewn by the following calculation:
The area of the cylinder is about four thousand and seventy-one square inches.
A pressure that will alter the barometer about the eighth of an inch is equal
to about an ounce on the square inch; an ounce per inch, or four thousand
and seventy-one square inches, is equal to two hundred and fifty-four pounds;
and two hundred and fifty-four pounds acting upon carriages on a railway
will (ou a level) move twenty-five thousand four hundred pounds, an amount

page_text: which as it will be more than one vehicle would bear, must be divided. But
this amount, large as it is, is by no means the whole of what might be
transported at one time. Supposing the exhausting were to be to a degree which
would sink the barometer two inches lower than one exposed to the atmosherc
stood at, a pressure of above four thousand pounds would act on the vehicle,
which on a level would move above a hundred and eighty tons at one and the
same time, and increased exhaustion will increase this weight. The nature of
the ground will to be sure make a difference in this respect. With reference to
this it is to be observed that, provided the ground rises gently and gradually, I
prefer continuing the course of the cylinder so as to pass over rather than
round it. Since as the way in which the vehicle is fitted for moving in the
cylinder prevents its upsetting, as owing to this it is of no consequence how
fast it goes down hill, and as the momentum it may thus acquire will be
advantageous in other ways than merely carrying itself forward, the extra
labour of getting it up bill will not be thrown away. It is with a view to this
that the vehicle is constructed with one wheel in order that it may adapt itself
to rises and falls. In a cylinder in which the rises and falls or turns are in
the least abrupt, it is best however to have the body of the vehicle several
inches smaller than the cylinder, and with only one of the end ribs of nearly
the same size as the cylinder, as the vehicle may then be adapted to shorter
turns. The same thing which relates to the weight also takes place with
reference to the velocity which, (as air is known to rush into a vacuum at the
rate of nearly a thousand miles an hour), may be increased to be above one or
perhaps even above two hundred miles an hour, according to the number of
pumps made use of; with reference to this, and to allow of the velocity with
which the vehicle may be made to move being increased to the maximum
whenever it may be desirable, I make provision in the following manner :--
It is evident that the making use of a sufficient number of pumps will render
the greatest rate at which air can rush along the cylinder, the limit in point of
velocity. Now as the friction of the air against the inside of the cylinder
would very considerably diminish this rate, provided the air could be admitted
behind the vehicle only at the end from which it started, at about every mile
(or more or less if desirable) of the cylinder's length, there is put into it (at
the time it is fixed) a valve of the following kind:-Figure Eleventh is intended
to represent a piece of the cylinder in the position it is fixed in with a valve
attached to it. A, A, is the cylinder; the hanging piece B the part in which
the valve is, and for convenience of illustration, the support by which the
cylinder is carried is not shewn. The hanging part B is cast to fit to the
cylinder, as shewn by Figure Twelfth, which gives a view of it as from beneath

page_text: the cylinder, shewing how it is mitred or shaped to fit the cylinder. Where it
connects or hangs to the cylinder it has a flanch or flange cast to admit of its
being bolted to it, and of a cement joint being made between them. From the
cylinder where this part in which the valve is is attached or hung to it, a piece
is to be cut out of the size of this hanging part, to admit of air rushing into
the cylinder from the valve, or the cylinder may be so prepared in the first
instance. Across the hanging part where this piece is cut out of, (or hole is in
the cylinder), and at such a height, and in such a direction as will render it
both level and in a right line with the wheel track onthe bottom of the cylinder,
is to be fixed a piece of iron to form a wheel track or bridge over the valve,
capable of bearing the weight of and enabling the vehicle to pass over this hole.
This bridge piece must be formed at top like the wheel track bolted to the
bottom of the cylinder, but may be arched underneath to render it stronger.
It may be fixed by bolts to the inside of the hanging piece, and is to be so
finished as to admit of the vehicle passing along it over the hole opening to the
valves, as it would along any other part of the cylinder. The valve which is
placed beneath this bridge piece consists of a rim or hoop of iron, about six
inches deep, by such thickness as will render it strong enough for the purpose;
suppose something above a quarter of an inch across this rim, sheet iron or
copper is extended, so as to render it similar (in point of shape) to the lid of a
canister. This sheet iron may be strengthened, as is necessary, by pieces of thin
bar iron running radially across the valve, from the center to the circumference,
to which it may be connected. The rim of the valve is attached to some part of
the inside of the hanging piece by a hinge or joint, so as to admit of its rising up
and falling down like the lid of a canister when it is opened or shut; above this
hinge or joint is a pulley through which a line or chain is to be run with a weight
attached to one end of it. The other end is to be connected to the valve that the
weight may operate as a balance or counter-weight, and admit of its being easily
raised. Inside the banging part, near the bottom, and at right angles to the side
of it, is attached a rim or projection about six inches wide, so as to form a kind
of shelf. To this picce, at right angles with it, and parallel with the side of
the hanging part, is fixed a kind of side about three inches high. These parts
are shown in section by Figure Thirteen, where A points to the bottom
and to the side of this rim or projection. By this it will be conceived
that this projection being carried all roundt he inside of the hanging part,
and attached properly to it, will form a kind of circular cistern or trough
about six inches wide by three deep all round the inside of it. This cistern
is to be nearly filled with mercury, and the hinge or joint to which the rim
of the valve is attached being so fixed as for the edge of the valve to drop

page_text: down into this cistern, a little farther explanation will shew that it may be
rendered air-tight. B, Figure Thirteenth, is meant to represent (in section)
the inside of this hanging part. a is the bridge for the vehicle to run on
over the hole. c is the counter-weight. d is supposed to be the hinge or
joint on which the valve moves. A, the valve, with its edge or rim in the
cistern in which the mercury is to be. e, a catch, to keep the valve shut.
With things in this position, and with the cistern full of mercury, it is
evident that no air can pass up into the cylinder without displacing the
mercury, by pressing it down from one side of the rim of the valve and raising
it up on the other, which it will not do under an exhaustion that should sink
the barometer only two inches. Under these circumstances, therefore, the
valve is tight. On the catch e (which being of steel, and fixed at f, springs
out and catches the top of the valve so as to hold it down) i is an angular
or wedge-like projection; above this projection is a rod which moves through
holes in the supports g, g, and through the bridge or wheel track above, where
it projects and stands an inch or two above the bottom of the track.
On this rod at h is a shoulder under which is a spiral spring, which
by pressing against the support 9 keeps the rod projecting above the
bottom of the wheel track. At the bottom of this rod is a wedge-like
picce j. With things thus arranged, whenever the vehicle passes over the
valve the wheel presses the top of the rod k down. When pressed down the
part j at the bottom of this rod forces the catch i, e, back and liberates
the valve, so that it may rise and admit air into the cylinder. The valve
itself consists of sheet iron attached to the rim or hoop, and strengthened by
radial pieces, as before stated. It is made in this way in order that it may
be as light as possible, and when the counterweight is attached to it it may
be so adjusted as for a pressure equal to a few pounds acting on the under side
of it to raise and open it, though when this pressure is removed it will fall
down again. Now the surface of this valve being about four thousand square
inches, a pressure of a few grains per inch on its under surface will amount to
the difference between it and the counterweight and place them in equi-
librium. A pressure greater than this will consequently lift the valve up,
provided the catch i, e, be drawn back. Now as the vehicle presses back the
catch every time it goes by the valve, as has been described, it follows, that if
the friction of the air as it rushes along inside the cylinder should at any time
be so great as materially to diminish its velocity, and consequently prevent its
acting on the vehicle as it passes the valve with a pressure less than that of
the atmosphere by about a dram per square inch, the valve will be lifted up,
and air will rush in by it and operate on the vehicle, though as soon as this

page_text: pressure is removed from the valve it will fall down and shut again. By
placing valves of this nature at every mile (or more or less if desirable) do I
prevent the friction of the air against the inside of the cylinder from reducing
its pressure on the vehicle more than a quarter of an ounce per square inch
when the vehicle is moving with a velocity approximating that at which
air will rush along the cylinder. As, however, the nature of this provision
implies that it relates only to velocities which approach that at which air will
rush along the tube, and as there is reason to believe that rate is several
hundred miles an hour, the cases in which it will be necessary that this
arrangement shall operate may be very rare. The door or valve which has
been referred to as stopping the end of the cylinder is constructed thus:-
It consists of a kind of lid or cover large enough to go over the end of the
cylinder as the lid of a canister closes the hole in it. It may be of cast iron
about an inch thick, strenthened by ribs radiating from the centre to the
circumference. It is fixed by a hinge at the top of the cylinder in some such
way as what are called "manhole doors" to (dome) brewing coppers are
fixed, with a very strong screw opposite to the hinge fitting into a nut in the
cylinder, that it may be drawn tight to it, and also with a pully attached
to it to hoist it up and open it. The inside of it, where it shuts against
the edge of the cylinder, is to be faced quite smooth and level) by its
being turned or bored (or in any way that may be convenient) so as to
cause it to take a fair and even bearing against the end of the cylinder
all round, the end of the cylinder being squared properly off to render the
junction close and good. On the valve where it has been faced is then to be
attached by any convenient means of adhesion (by its being glued for
instance) a ring of soft thick leather of about three inches wide, composed of
segmental pieces laid close to each other, so as to cause the edge or end of the
cylinder to take a bearing against them when the valve is shut; when this
leather ring is attached it is to be well rubbed with soft grease to cause it
to make a tight joint, and if when this is done the valve be lowered to admit
of its closing the end of the cylinder, and the screw by which it may be
squeezed close to the end drawn tight, a joint that will prevent the entrance
of air to any great amount under the pressure that has been referred to will be
made, especially as with the increase of exhaustion will increase the pressure
by which the valve is forced against the end of the cylinder. In this (or in
any way that shall be convenient) may the valves be caused to close the ends
of the cylinder. Between the circumference of the vehicle and the cylinder
will be a small space or crevice about the twentieth of an inch wide, which
cannot be closed so as to be air-tight without causing friction to a degree

page_text: that would be more injurious than letting it remain open; since as this
crevice is not equal to one thousandth part of the area of the pumps, the
impeding effect which would arise from its being left open might be counter-
acted by working the pumps faster, or by having an extra pump or pumps
on purpose to allow for this and for other leakages which may perhaps take
place. In order, however, as much as possible to stop this crevice without
causing friction, on the end ribs, just within their circumference, are to be
glued narrow pieces of bear's skin, (or any other skin the hair of which is long
and thick), with the hair so disposed as for the air in endeavouring to rush
through the crevice to force it forward and partially close it. If this be
done there will be over the crevice a medium which, without causing fraction
that will be left against the cylinder as the vehicle moves along, will so
impede the passage of air as to render what does get in of little consequence.
This is the combination of apparatus by which persons may be conveyed or
goods transported, and as this combination of apparatus admits of it whenever
it may be desirable so to do, I cause the vehicle to be moved by forcing
air in behind it instead of exhausting it from before it, which I effect in the
following manner :-Shutting and opening the cocks in the pipes connected to
the valves of the air pumps, so as to render them condensing instead of
exhausting pumps, and closing the end of the cylinder which is nearest, and
opening that which is furthest from them, air is forced in behind the vehicle
instead of pumped out from before it, which has the effect of moving it, as
under the other course of operation, though in a reverse direction and to less
advantage, since as power is thus lost in the first instance, (that is in condensing
the air, trifling as this condensation may be), as the friction of the air against
the inside of the cylinder is greater with reference to a plenum than it is with
reference to a vacuum, and as it is impossible when operating in this way to
counteract or render this friction of no consequence, as the valves that
admit air into the cylinder do when operating by exhaustion, the labor is
increased to a degree which will prevent this method of operation from being
adviseable as a constant practice, though it may perhaps be convenient occa-
sionally to make use of it as an auxiliary. To this method of moving the vehicle
by pumping the air in behind it (by a plenum, that is), I however claim no
exclusive right. This is the combination of apparatus by which persons may
be conveyed, or goods transported. To the separate parts of this combination
of apparatus I make no claim, excepting as may herein-after be excepted.
But the combination of the whole I consider as my Invention and claim as my
right, excepting as relates to moving the vehicle by pumping the air in behind
it (by a plenum, that is), to which I claim no exclusive right whatever.

page_text: .
By the operation of this combined apparatus, persons may be conveyed
or goods transported from and to places that are ten, twenty, thirty, or
even a hundred miles apart. In order, however, that the necessary operations
at each end of the tube through which persons may thus be conveyed, or
goods transported from one place to another, may, notwithstanding their
distance, be simultaneous, and to render this mean of intercourse properly
effective, and enable us to inform those who direct operations at one end
when the vehicle is ready to start from the other, that the pumps may be set
going at the proper time, and errors or accidents prevented, another mean of
intercourse by which intelligence of that nature may be almost instantaneously
communicated is necessary. And this mean I effect by the combination
of apparatus mentioned secondly at the beginning, by the operation of
which water may be caused to communicate intelligence from one place to
another as follows:-It has long been known that if a pipe, with a cylinder
and piston at each end of it, were extended between two distant places and
filled with water, by pressing down the piston in the cylinder at either end, the
water might be caused to move forward in the pipe from that end toward tho
other end, and the piston there moved in a direction tending from the pipe of
communication. And equally long has it been known that the motion thus
communicated to a piston could be in one direction only, that is, from the pipe
of communication. Now the mean of intercourse by which intelligence may be
communicated that I have invented, consists in a combination of apparatus (to the
invention of or exclusive right to the seperate parts of which I make no claim)
whereby we are enabled to cause pistons in cylinders situated in places very
distant from each other, and connected by a pipe, to move to that pipe equally
well and promptly, as we can cause them to move from it, although the piston
to which the motion is communicated be much lower in point of situation than
the one from which it is communicated, and vice versa, thereby enabling as to
give two fold (that is, forward and backward) motion to a piston, and to cause it
promptly to return to the place from which we moved it, and also enabling us,
in consequence of this, to indicate or point out letters or numbers, or words in
succession, so that persons at one end of the pipe may convey information to
persons at the other end, notwithstanding their distance. The method by which
this is done is as follows:-Along, but underneath the ground, between the
two ends of the cylinder, and in a line with the course of it, a pipe must be
extended, reaching from one to the other of the places from and to which the
cylinder runs. This pipe may be of any convenient metal, but strong enough
to bear a pressure, which may, in some cases, amount to several thousand
pounds per square inch. It may be of any size that circumstances may render

page_text: desirable, though on account of the momentum which a long column of
liquid acquires if a motion at all rapid be communicated to it, it is best
to have it small, that this moinentum may be counteracted by friction against
the pipe. For this reason, therefore, it will be here referred to as of only
an inch or an inch and a quarter in the bore or calibre, and it may, under
some circumstances, be desirable to have it smaller even than this, and
perhaps only half an inch in diameter. The seperate lengths or pieces of
which it is composed may be put together in any way that is convenient, so
that the joints are perfectly tight, both as relates to air and water. It is to be
placed in a trench dug in the ground, about three or more feet deep, so
as to keep it of an uniform temperature, and as much as possible prevent
expansion and contraction, and also so as to keep it out of the reach of frost,
and prevent the water in it from being congealed and solidified by cold
weather; in such parts of it as the nature of the ground renders higher than
others must be one of those valves which admit of all air being driven out of
pipes whenever it is wished to fill them with water. This valve is shewn
by Figure Fourteenth, where the pipe is supposed to be crossing a high
ground. V is the valve which opens downwards into the pipe, & which is
situated in a very strong conical vessel about a foot deep by nine inches
in diameter at bottom. Fixed to the under side of this valve is a hollow
copper ball o, of such diameter as will render it capable of floating the valve
and shutting it whenever water rises so high as to issue out by it. This small
vessel, in which the water is situated, is connected with the pipe so as for
the pipe to open into and have free communication with it, and under these
circumstances if water be forced into the pipe it will drive all the air out by
the valve; but as soon as the water rises high enough to issue by it, the hollow
ball floats the valve, and causes it to rise and close the orifice, thereby allowing
the pipe to be emptied of air, but preventing the escape of water to any
amount that will signify. In this way the pipe may be emptied of air, since
of valves of this kind are put in those parts of it. which pass over high ground,
and into which the levity of air would cause it to rise whenever there is accu-
mulated a quantity of air sufficient to displace water enough to let the
weight of the valve overcome the buoyancy of the hollow float beneath,
the valve will open and cause the pipe to become emptied of air and filled
with water. It will be perceived that both the reservoir in which the valve
is fixed and the float must be strong enough to bear the pressure to which
they will be subjected, and that the float must be large enough to lift
the valve as soon as it becomes surrounded with water. One end of this
pipe is brought to any convenient building near one end of the large

page_text: cylinder, through which persons are conveyed or goods transported, and
the other end is conducted to a similar building near the other end of the
large cylinder. In each of the buildings to which the ends of the pipe are
conducted is fixed horizontally a cylinder of the same size as the pipe, or larger
should circumstances render it desirable. In the present instance it will be
considered as the same size as the pipe, that is, about an inch and a quarter
in diameter. These cylinders, or rather this cylinder (since, to avoid confu-
sion, I will refer to only one end of the pipe, though what is said must be
understood to apply to both ends), is in the present instance to be thirty
feet long, though it may be longer or shorter whenever desirable. It may be
composed of different lengths of cast brass tube, with flanges or flanches at the
ends, each of which must be so bored inside, and with its flanches so faced, as
to admit of its being bolted together to form one long cylinder in which a
piston may move as in a pump barrel. This cylinder is to be so fixed to one
end of a piece or pieces or frame of timber about ninety feet long, laying
horizontally, as shall render it firm and keep it straight. One end of it is to
be connected to that end of the pipe extended between the two places which
comes to the building in which it is fixed; the other end is to be open to
receive a piston. To this cylinder is to be fitted a piston with a rod as long as
or rather longer than the cylinder is, and as large as will go into the cylinder.
At about thirty feet from the open end of this cylinder (at the other end of the
ninety feet frame, that is), in a line with its centre, is to be fixed another
cylinder of the same kind, of the same length, and with a similar piston and
rod to it. The end of this cylinder which is nearest to the first-mentioned
cylinder is to be open to receive the piston. The other end is to be connected to
a mitallic vessel about two feet in diameter by ten feet long, of such thickness
as to be capable of bearing a pressure of several thousand pounds per square
inch, and so cast (if of cast iron, or put together if of wrought iron or copper)
as to be in effect an air vessel. To this vessel is to be attached a condensing
pump, by which it may have air forced into it to the degree of one hundred,
two hundred, three hundred, or more atmospheres, with a guage to indicate
the pressure.
At about every foot of that part of the ninety feet frame which
is between the ends of the two cylinders, and so as for their centres to be
concentric with those cylinders, are to be fixed pieces of cast brass similar to
Figure Fifteenth. These pieces of cast brass are to serve as stays or guide
pieces to the piston rods, being just large enough for them to move in. The
notch or break in them is to allow a strong key or handle, by which the piston
rods are moved, to pass through. Supposing these things to be done, we
have a piece or pieces (say a frame) of timber about ninety feet long, laying

page_text: horizontally, on one end of which is fixed the cylinder (which we will, for
distinction's sake, term the "water cylinder"), connected to the pipe of com-
munication, and on the other that connected with the air vessels (and which
we will term the "air cylinder"), the open ends of these cylinders being toward
each other, with a space of about thirty feet between them and their direction
each to the centre of the other, so as for their pistons to move in the same
line, and admit of their rods being connected, that the movements of the two
pistons may be simultaneous. This is accordingly done by the piston of one
cylinder being thrust to the inner, while that of the other is brought to the
outer end of their respective cylinders, and the two rods are united at the
point of junction by going into a short piece of strong tube or pipe (the outside
of which is to be of the same size as the rods, that it may go through the stay
or guide pieces fixed to the frame), to which they are fixed by keys or pins,
the ends of the rods being previously reduced to fit the inside of this tube.
Through this piece of tube or pipe, previous to its being fixed to the rods, is
cut a mortice about three inches long by a quarter of an inch wide, to which
is adapted a key. This key may be fixed, when in this nortice, by a pin
going through the tube and it. To this key is attached a handle shaped like
Figure Sixteenth, the stem of which may be two feet long, and the cross piece
four fect, to admit a man to take hold on each side that it may be moved
backward or forward. On or above the frame, between the water cylinder
and the air cylinder, are now to be marked the letters of the alphabet (or
figures, or words, if more convenient), with a space of a foot between them, as
shewn by Figure Seventeenth, where 1 represents the end of the pipe of com-
munication; 2, the cylinder connected to it, or water cylinder; 3, the ninety-
feet wood frame; 4, the piston rods between the cylinders; 5, the key (and
which also serves to point out or indicate the letters of the alphabet and sen-
tences above it), to and on which the handle, Fig. 16, fits, to move the pistons
backward and forward; 6, the cylinder connected to the air vessel or air cylinder;
7, the air vessel. With things thus arranged, the pipe of communication is
to be filled with water (or any incompressible liquid) by forcing it in by a pump.
(connected to the pipe by another pipe and a cock) in either of the buildings..
When all the air is driven out, and the pipe is so completely filled with water
as to have driven the piston in the water cylinder at the end of it (and conse-
quently the piston of the air cylinder also) as far from the end of the pipe as
they can move in their respective cylinders, air is to be pumped into the air
vessel at that end of the pipe which is highest till the guage indicates a
pressure of suppose one hundred pounds an inch, when water is to be Ite out

page_text: of the pipe (by a small cock previously inserted for the purpose, just where
it is connected to the cylinder) till the pressure of the air on the piston of the
cylinder attached to the air vessel, (which piston is connected to the other by
their rods, as has been described), has driven the two pistons and rods so far
back as for the indicator (5) to stand at or opposite or so as to indicate A.
When this is done, air is pumped into the air vessel at the other or lowest end
of the pipe till the pressure of that air on the piston of the cylinder connected
with it is strong enough to move that piston and consequently the other con-
nected to it, the water in the whole lengths of the pipe and the pistons at the
other end. This forcing air into the air vessel at the lower end of the pipe is
to be continued till the indicator (5) at that end stands at or indicates O,
when it may cease. When these things are done we have between the two
buildings, from and to which the pipe leads, a quantity of easily moved but
incompressible liquid, which is, by the shape of the pipe, caused to assume the
form of a solid cylinder or rod, and which, if thrust strongly forward from one
end, will be caused by the inflexible nature of the pipe to act or push against
the piston of the cylinder at the other end so as to move it forward, and
which, if the piston at that end from which it has been pushed forward be
drawn back again, will be caused by the action of the condensed air at the
other end to go back also as far as that piston is drawn back, so as to admit
of the other piston's coming back a similar space; and by which (in short) the
piston at one end may be caused to move a certain and definite space, either
backward or forward, by moving the piston at the other end a similar space in
a similar direction. Having thus established a mean of communication,
proceed we to cause it to indicate our sentiments correctly from one end to
the other. It is to be considered as a rule, that the indicator (5) at each end
is always to stand (when not in motion) at a pointing out one of the middle
letters of the alphabet, (O for instance), as there it is best situated for moving
towards any other letter. The first thing, therefore, after having got the pipe
filled with water, is to get the quantity in it so adjusted as to cause the indi-
cators to designate O at each end. This is an arrangement, however, which it
takes some time (perhaps a day or two) to get exactly right. But by attention
and watching the indicators, and pumping a little more water in a letting a
little out, and varying the condensation in the air vessels till the spring of the
air in that at the lowest end of the pipe exactly counterbalances the joint
pressure from the other air vessel, and the superior altitude of the water at
that end of the pipe, by attention to these things and written correspondence
between the two ends, stating particulars it may be necessary to communicate

page_text: after some trouble, and in the course of a day or two, this adjustment may be
effected. When it is effected, if the indicator at one end (suppose by two men
taking hold of the handle it is moved by) be moved from 0 to N, the whole
column of water in the pipe will be pushed a corresponding space, and cause
the indicator at the other end to move till it stands at or indicates N also.
If it be then drawn back to P, the pressure of the condensed air in the air
vessel at the other end acting first on the piston of the air cylinder & by means
of the rod which connects that piston with the piston of water cylinder upon
both, that piston and the water on the other side of it will cause the whole
column of water in the pipe to come back also, and consequently the indicator
to move till it indicates P at that end. By thus causing the water to move
from us through the whole length of the pipe, by pushing the handle or
indicator, and by also causing it to come back again toward us whenever we move
the handle back again, in consequence of the pressure which the air vessel at
the other end throws on it, by arranging thus we get a pressure on the piston
at either end, which will always keep it close to and to cause it closely to follow
and accurately to indicate the movements of the water at the other end, since
if by means of the handle or indicator we push the water from us, that water
acting on the piston at the other end will cause the indicator there to move a
distance corresponding with that which we have moved the other. And if we
then move that handle & indicator back again, the pressure of the air in the
air vessel at the other end acting on the piston in the air cylinder so as to
cause it, in consequence of their rods being connected, to keep the piston of
the water cylinder at that end pressed hard enough against the water to move
it will cause that piston and consequently the. indicator to move back the same
distance the other has been moved, and so as to indicate whatever letter it
was stopped it. By thus causing the indicator at the other end of the pipe
to go forward exactly the same distance we move the indicator at the end
where we are operating by the agency of the mobile but incompressible liquid
between them, and by also causing the indicator at the other end to come
backward just the same distance, we move the indicator at the end where
we are operating backward by the agency of the condensed air in the air
vessel; by arranging, 1, thus we may cause the same letter to be at the same
moment indicated at each end, and, consequently, by indicating first one
letter and then another, can cause information to be communicated. If in the
place of those letters of the alphabet which may be dispensed with in telegro-
phic communication being on the frame, sentences (or numbers referring to
them), such as "The vehicle is nearly ready," "Start the engines," "The vehicle
is off," &c., &c., be placed on the frame, one movement will communicate the

page_text: whole of the information it will (generally speaking) be necessary to give,
though the alphabet will still remain for communications which must be
indicated letter by letter. It is necessary that the air vessels should be large
in order that the greater or less condensation that takes place in them, as the
pistons of the cylinder connected to them are moved to and fro, may not
make any operative difference between the pressure which takes place against
the piston when it is at one end of the cylinder, compared with what it is at
the other. Since as the moving the air piston from one to the other end of
its cylinder will make a difference of above a gallon in the quantity of air in
each air vessel, these vessels must be large in order to render the variation of
pressure which, in consequence, takes place, inoperative (as to visable effect,
that is) on the pistons. It is necessary that the handle which moves the
pistons should be moved very slowly indeed, in order to prevent momentum
being imparted to the water so as to cause erroneous indication. It is also
necessary that the degree of condensation in the air vessels should be sufficient
to overcome the resistance caused by the friction of the pistons and rods, the
friction of the water in the pipe, its altitude at the higher end, and the
momentum of the water when in motion, with reference to which it is to be
observed, as follows:-It is known that if a long column of water in a pipe
be put in motion, it acts on the end to which it moves with a momentum
proportioned to the velocity of its motion. Now, in addition to employing
condensed air to give retrograde motion to the pistons and water, as has been
stated, I also employ it to counteract and neutralize this momentum.
though I guard against it generally speaking, both by using a small pipe
(which, in consequence of the increased surface, causes more friction than a
larger one, and therefore lessens momentum), and by moving the pistons and
water very slowly, yet as these precautions will not of themselves be sufficient,
I make use of condensed air in the way that has been stated, and the effect of
which, in this particular, is as follows:-The general operation of this air is
to press equally in both ends and keep the pistons of the water cylinders at
each end close to the water so as to drive it back; but when an indication is
made from one end, the operation of this air on the whole column of water in
the pipe being withheld at that end by the handle or indicator being held and
kept stationary, as soon as it gets opposite the letter to be indicated, the
operation of this air at the other end, provided the water should tend to move
farther than the indicator has moved in consequence of momentum, becomes
opposing to the amount of its condensation, and tends to counteract this
momentum by throwing a pressure upon the water which acts as an opposing
and resisting power, and which will absorb and neutralize momentum that is
Since,

page_text: not superior to its resistance. Condensed air is in this way employed for a
purpose different and distinct from keeping the pistons in the water cylinder
at each end pressed close and hard against the water; and also different from
that of moving the whole column of water and the pistons at one end when
the indicator is drawn back at the other end, though it is made use of for
these purposes too. It can scarcely need stating, that I increase this conden-
sation to any amount that may be necessary for these purposes, or that I
substitute a larger air cylinder in the place of that which has been described
whenever necessary; or that under such circumstances, instead of moving the
piston rods by a mere lever or handle, which two men can take hold of and
walk backward and forward (and which has been referred to here solely
because it was the simplest mode and least incumbered the Drawing with
parts or the description with detail), I employ any convenient machinery that
will increase power as may be necessary. The length of the communication
pipe in the present instance is supposed to be ten miles, and the places to
and from which it leads nearly level with each other. When the places between
which it is to communicate are farther apart or differ much in situation,
as relates to altitude, the condensation in the air vessel must be proportionably
increased to provide against the increased momentum of a longer column of
water, and to enable it to cause the water to retrograde when the piston at the
other end is drawn back. Whenever it may be desirable, I vary the size of
the pipe, and size and length of the cylinders. With reference to which it
may be observed that the larger the cylinders are in proportion to the pipe, the
less is the liability to error, though the time taken up by each communication
will be greater; as, for instance, supposing the area of the bore of the pipe to
he only equal to the hundredth part of a square inch, when that of the cylinders
was equal to a square inch, any circumstance, (such as air getting in or
expansion or contraction of the water, owing to the weather becoming hotter
or colder), which should cause defective transmission through the pipe, would be
diminished in the proportion of a hundred to one in its operation on the
pistons, and the liability to false indication consequently lessened. Error of this
nature is however guarded against in the following manner:-As water expands
and contracts with variations of temperature, and as the water in this pipe may
in summer be heated and in winter be cooled, I guard against erroneous
indication from this cause in the following manner, The particulars to be
attended to by the persons who work and match the pistons and indicators are
that the indicator of the cylinder they attend is always to be kept pointing to O
(or one of the middle letters of the alphabet) in the following manner,-In any
convenient part of the building is a small pump by which water may be forced

page_text: into the pipe at the end of the cylinder, and in this pipe is a small cock; should
any contraction of volume take place in the water in the pipe, so as to cause
the piston and consequently the indicator to move back from O towards A, a
small quantity of water is forced into the pipe by this little pump, so as to
move it to O again; and should on the contrary expansion take place so as to
move the indicator from O towards Z, the cock is open to emit so much as
will bring it back to O again, and by attention to these particulars the
indicator may always be put right as soon as the expansion or contraction is
perceptible. There will be no danger of mistaking the effect of expansion or
contraction for an indication from the other end, as the former will in
comparison with the latter be gradual and minute. The condensation in each
air vessel, and consequently the pressure by which the pistons are kept
constantly close to and caused to inove the water whenever the piston at the
other end is moved backward from the pipe, may be lessened or increased, as
the situation of the two places, and the nature of the ground between them,
renders necessary. Should the two places be on a level, and the ground between
them so, a pressure of one hundred pounds for each square inch of the area of
the pistons might perhaps be enough. But when one place is higher than the
other, and when the ground between is hilly, a pressure of above one hundred
pounds for every square inch of the piston's area may be necessary. It is best
however to err on the safe side, and have too much rather than too little
pressure, both to guard against the friction of the water in the pipe, against that
of the pistons and rods in the cylinders, to provide against momentum in the
water, and to cause the pistons at one end promptly to move the water
whenever the indicator at the other end is drawn back. In order to avoid
inconvenience from the expansion and contraction of the pipe, it is best to lay
it when the heat of the weather is about fifty degrees, which may be considered
the mean temperature with us, though this may be obviated by curving it a
little so as to prevent expansion or contraction taking effect on one long right
line, or by having stuffing box joints, so as to allow the end of one pipe to
slide in the other in those parts where it may be impossible to bury or shelter
it, so as to prevent the extremes of heat or cold from taking effect on it.
Should any circumstance render it more advisable, I apply a weight or weights
acting over a pulley to impart the backward motion to the piston and water at
one end of the pipe when the piston is drawn back at the other, instead of
these air cylinders and pistons and vessels. And should that also be desirable
I move the pistons to and fro so as to indicate the letter by machinery instead
of by two men walking to and fro, as is necessary to move the handle or indicator.
It may be that in some situations, and where the place to which one end of the

page_text: pipe leads is much higher than the place to which the other end goes, I use
an air vessel only at the lower end of the pipe, and derive the backward motion
from the superior altitude of the other end. But although this is possible,
yet owing to the uncertainty with which it might be attended, and the
(then) absence of a counteractive to momentum, I do not recommend it to
be done. In laying the pipes across brooks or rivers, it is best to take
advantage of bridges, deviating, for that purpose from the line that might
otherwise be followed to have the benefit of the bridge, and should it
happen that the pipe cannot be so buried in crossing them as to prevent
the water in it from being frozen if left stationary, I guard against it in
the following manner:-In one of the buildings to which it leads must be
a well, and in this well a pump. The pipe leading from this pump is con-
nected by a cock to the pipe leading from this to the other building (that is, to
the communication pipe), in which a discharge cock is connected to the pipe;
when the weather indicates frost, the cocks are opened, and this pump is set
to work, when water of about fifty degrees of heat (that being the heat of deep
well water all the year round) is pumped into and through the pipe, so as to
prevent congelation taking place, both from the raised temperature and from
the water being kept in motion, and this being done at intervals proportioned to
the intenseness of the cold, and so as to keep the water in the exposed parts
of the pipe changed and prevented from remaining in those parts long
enough to be congealed, frost is guarded against. It can scarcely need stating
that communication and arrangements take place between the two ends
previous to this being done, stating when they are going to begin, for what
period the pump will be worked, and what interval will elapse between the
workings, &c., &c., so that the communication of intelligence may not be
delayed above a quarter of an hour at a time. Should it be necessary to
transmit any in the mean while, this is the mean of intercourse by which
intelligence may be communicated.
To the having first discovered that a piston may be moved or motion
communicated in one direction from a distance by the agency of water
in a pipe, I make no claim, because it has long been known, but the
principle of combining with this method of communication a mere impulsive
movement in one direction apparatus which should enable us in the first
place to neutralise or render nugatory the momentum which this mere
impulsive movement would give rise to; in the second place to cause the
column of water in the pipe to move towards us when we moved the piston
back, as well as from us when we pushed it forward, notwithstanding the
other end of the pipe being perhaps several hundred feet lower than the end

page_text: at which we were operating; in the third place to empt or free the pipe
entirely from air, so as to prevent erroneous indication from its expansion or
contraction; in the fourth place to counteract expansion or contraction in the
water from change of temperature, and consequently guard against the erroneous
indication from that cause, and which, in the sixth place should enable us to
point out or indicate letters or numbers or words in regular succession,
the principle of combining apparatus of this kind with the known method of
communicating mere impulsive motion in one direction I consider as my
Invention, and claim as my right. Should circumstances render it desireable I
make use of this mean of intercourse, by which intelligence may be communi-
cated for a purpose distinct from and without reference to or connection with the
mean of intercourse by which persons may be conveyed or goods transported in
the following manner :-It has long been known that the methods of telegra-
phic information hitherto practised are liable to the objection that wet and foggy
(or even hazy) weather, and darkness, render them frequently useless during
the day, and always so at night; but notwithstanding the inconvenience which
has sometimes been experienced, in consequence of this inability to communicate
telegraphically except during daylight and clear weather, no system of
telegraphic intercourse, on the principle of causing water confined in a pipe,
extended between places, to indicate letters or numbers, or words, has hitherto
been practised. Now whenever it may be desireable so to do I make use of
apparatus on the principle that has been described for the purpose of tele-
graphic communication, independent of and without relation to the mean of
actual communication by which persons may be conveyed or goods transported,
having either one or more pipes with cylinders and pistons (though both
longer and larger, if desirable) connected to them, as has been described, and
with either figures or sentences in the place of the letters of the alphabet;
and should it be desirable so to do, I attach a rack to and cause the piston rod
between the two cylinders to move a wheel, on the axis of which is a pointer
that indicates letters, or numbers, or sentences on a circular plate, instead of
placing the letters, or numbers, or words, as has been stated.
The invention of, or any exclusive right to, the principle of communicating a
mere impulsive motion in one direction, that is, from the pipe to a piston in a
cylinder at the other end of a pipe, I again disclaim; but the combination of
apparatus by which, in consequence of the operation of the air vessel (or some
convenient substitute), water may be caused to indicate a letter or figure, when
it is allowed to come back as well as when it is forced forward (let either end
of the pipe be as much lower than the other as it may), and rendered a mean
by which letters or numbers, or words or sentences, may be consecutively

page_text: indicated, and a mere principle of motion in one direction consequently
rendered a mean of uninterrupted telegraphic communication, - the com-
bination or combinations of apparatus by which this may be done I consider
as my Invention, and claim as my right.
Should any circumstance render it desirable so to do, instead of driving
or moving the vehicles by pumps fixed at the ends of the tube through
which persons are conveyed or goods transported, I cause them to move by
engines and pumps fixed in them, which operate to pump the air from one
side of the vehicle to the other, and consequently producing greater pressure
on one side the vehicle than on the other, cause it to move towards the side
on which the diminution takes place. This way, however, I by no means
recommend for practice, though it may possibly on some occasion be con-
venient as a resource.
It has been stated, that, with exceptions which might be made, I had not
invented, nor did I claim, the exclusive use of the different parts of the com-
binations of apparatus that have been described; be it, therefore, known that
these exceptions relate, firstly, to the method by which the concussion of the
vehicle is diminished, or, in other words, the springs it is carried by, which, as
condensed air confined in a cylinder or cylinders by a piston or pistons has not
before been used to diminish the concussion or soften the motion of vehicles,
I consider as my Invention, and claim as my exclusive right in its application
or use as springs to or for the purpose of softening the concussion or jolting
of vehicles, whether put in practice on the scale here referred to or on a
larger or smaller scale. This exception, relates, secondly, to the vehicle herein
described, with its wheel so situated as to run in one track or groove, a
channel or right line, whereby friction is diminished, which I also consider as
my Invention, and claim as my exclusive right, whether put in practice on a
larger or smaller scale than the one here described. This exception relates,
thirdly, to the apparatus for obviating the friction of the air inside the tube,
whether that apparatus be such as shewn by Figures Eleven, Twelve, & Thir-
teen, or constructed and applied in any other way which the principle of
obviating friction by admitting air into the tube at any convenient parts of its
length, beside the ends, will admit of.
It is to be observed, with reference to Figure Seventeenth, that as the scale
it is necessary to use to represent a figure ninety feet long would, if adhered
to for the whole of the figure, have rendered the air and water cylinders and
pistons so minute as for them to have appeared scarcely more than lines, that
scale is departed from, as relates to the diameter of the cylinders and piston
rods, though it is adhered to as relates to their length.

page_text: Should circumstances render it desirable, I have the cistern or trough in
which the quicksilver is (Figure Thirteenth), and the edge or rim of the valve
which goes into it, deeper, so as to admit of exhaustion to a degree which
would lower a barometer as much more than two inches as it may be wished
to increase the pressure of the air on the vehicle. The wheel of the vehicle
also I increase in size as circumstances may render desirable. Also do I
vary the size and shape of the tube, the method of its construction, and the
material it is made of, as circumstances may render desirable.
In witness whereof, I, the said John Vallance, have hereunto set my
hand and seal, this Nineteenth day of August, in the year of our Lord
One thousand eight hundred and twenty-four.