AN IMPROVED BALLOON AND APPARATUS FOR WORKING THE PROVISIONAL SPECIFICATION SAME, TO ENABLE THE AERONAUT TO FLOAT AT A HIGH OR Low LEVEL AT PLEASURE
Year: 1881

page_text: LETTERS PATENT to William Nelson Hutchinson, General in Her Majesty's
Army, of Wellesbourne, near Bideford, in the County of Devon, for an
Invention of "AN IMPROVED BALLOON AND APPARATUS FOR WORKING THE
PROVISIONAL SPECIFICATION left by the said William Nelson Hutchinson
. at the Office of the Commissioners of Patents on the 2nd May 1881.
WILLIAM NELSON HUTCHINSON, General in Her Majesty's Army, of Wellesbourne,
near Bideford, in the County of Devon. "AN IMPROVED BALLOON AND APPARATUS
FOR WORKING THE SAME, TO ENABLE THE AERONAUT TO FLOAT AT A HIGH OR
Low LEVEL AT PLEASURE."
Instead of, as is usual, making the balloon when floating in the air sink by
permitting the escape of gas, or rise by throwing away ballast, my Invention will
give the aeronaut the means of changing his altitude by enabling him to decrease or
increase the bulk of his balloon as often as he wishes without risk of its efficiency
or loss of any material.
For this purpose the balloon is made gas-tight, and its bulk is lessened for
descents and increased for ascents by mechanical means.
With an ordinary balloon the weight of the car is often borne by a net spread
over the upper part which supports the hoop or ring from which the car is
suspended by ropes. In my Invention, besides having such a net, the weight of
the car is nearly as much borne by a second net spread over a considerable portion
of the lower part of the balloon. The ropes from this lower net run through
pullies fixed to the hoops of both nets before they (the ropes) are attached to the
car. My balloon would be globular at the bottom.
In the annexed crude illustration, to avoid confusion, only 1 pr. of pullies is
shown, and one of the ropes which belong to the lower net. The upper pullies
have, say, two sheaves, the lower pullies, to each of which a rope is attached, only
one sheave. With a view to clearness the vertical distance between the pullies is.
shown preposterously great, for in reality an alteration by merely a few inches in

page_text: the vertical depth of the balloon would make it fall or rise. The principal object.
of the Invention is not to carry balloons to a great height, but to enable them to
remain for long periods floating in altitudes at a pleasant distance from the earth,
possibly for the aeronauts to explore unknown regions in various latitudes.
Supposing the car to be sustained solely by ropes from the lower net, the drag upon
that net (owing to the system of pullies) would be three times as powerful as
would be the drag upon the upper net were the car sustained solely by ropes from
that net. This powerful drag on the lower net gives the aeronaut the means, by
pulling on the ropes of the lower net, to make the nets approach each other, and
by thus compressing the gas to diminish the bulk of the balloon and cause it to
descend. Were the car sustained solely by ropes from the upper net, the balloon
would, by expanding to its utmost bulk, rise to the highest altitude it could attain.
All lesser bulks, therefore altitudes, would be regulated by the aeronaut's arrange-
ment of the pull on the two sets of ropes. For him to have perfect control over the
altitude of his balloon, it is evident that the car (which is the fulcrum) must
possess sufficient power, that is, sufficient weight with the aid of the pullies after
all stores of provisions, &c., are consumed, to compress the gas to the dimensions
that will bring the lower net as near the upper as was ever contemplated by the
constructor; weight beyond that is unnecessary. As the greater the number of
sheaves in the pullies, the greater is the compressing power, the less need be the
weight provided there always be sufficient to bring the car to the earth when the
nets are forced into close contact. The safety valve might then be useful. 1 (see
sketch) is one of many light rods attached, probably loosely, to the upper hoop, and
passing freely downwards through a large eye fixed inside the lower net. These
rods aid the skin of the balloon (the material of which it is made) in resisting the
increased pressure from the interior to which it is subjected at descents. Possibly
a linen band attached to the two hoops (when far apart), and pressing interiorly
against the rods, would surround the middle part of the balloon, and give further
assistance to the confining influence of the horizontal rows of the net when the
pressure from the vertical rows ceases on the hoops approaching each other.
A ring with holes in the circumference might be attached by elastic bands to
the bottom of the net of a vertical balloon in the horizontal plane A, B, (see sketch).
The ropes running freely through these vertical holes could not get intermixed, and
the possibility of the balloon ever turning on its side would be effectually
prevented.
With a view to prevent the disagreeable rotatory motion often experienced by
aeronauts, thin light wings might be attached vertically in the plane of produced
diameters of the uppermost hoop and of the hoop near A, B.
The prescribed principle for contracting and expanding could be made applicable
to most classes of balloons on being inade gas-tight.
The bows of a navigating balloon being stiffened, and the after part of the
balloon being used as a fulcrum, with the aid of the power which drives the
propelling blades (or wings), the bulk of the balloon could be diminished in its
length by a pull on ropes running through the pullies attached to a net embracing
the bows, and to a net over the stern part, so arranged as not to interfere with the
action of the propelling blades (or wings). A portion of the interior frame would.
have telescopic play. Probably the ropes before being attached to a windlass would
converge to sheaves fixed at the end of a long spar projected beyond the bows from
the after part. This appears a better plan than to contract. the waist of the
balloon by lateral circumferential pressure, or for machinery to act directly upon
the telescopic arrangement, as it would be extremely difficult to effectually prevent
the escape of gas..

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Nelson Hutchinson in the Great Seal Patent Office
on the 29th October 1881.
I t
WILLIAM NELSON HUTCHINSON, of Wellesbourne, Bideford, in the County of
Devon, General in Her Majesty's Army. "AN IMPROVED BALLOON AND APPARATUS
FOR WORKING THE SAME, TO ENABLE THE AERONAUT TO FLOAT AT A HIGH OR
Low LEVEL AT PLEASURE."
°
Instead of making, as is usual, the balloon when floating in the air sink by
permitting the escape of gas or rise by throwing away ballast, my Invention will
give the aeronaut the means of changing his altitude by enabling him to decrease
or increase the bulk of his balloon as often as he wishes without risk to its
efficiency or loss of any material. Usually an amount of gas is consumed much
beyond what would be required were it not necessary to make provision for some
to escape at all descents, and thus the balloon is at starting generally carried up
to a height that is rarely desirable. By my Invention only as much gas would
be wanted as would convey the acronaut to any altitute he judged most convenient,
and enable him to remain at that altitude for long periods. To effect this change
of bulk great pains are taken to make the balloon gas tight in every part. Its.
bulk is lessed for descents and increased for ascents by mechanical means.
With an ordinary balloon the weight of the car is borne by a net spread over
the upper part of the balloon. By my Invention, besides having such a net, the
weight of the car and of articles belonging to it is at all times partially borne, and
when the balloon's bulk is diminished by power exerted from a light car is greatly
borne by a second net spread over the lower part of the balloon. Moreover by
the existing system a net only on the upper part of the balloon protects it from a
bursting strain, whereas in my Invention every part is supported.
Figs. 1 and 2 represent non-navigable, Figs. 3 and 4 navigable, balloons. They
are shown fully extended. Near the mid-horizontal zone the net is attached to a
hoop or frame (A). Its edges are well rounded to prevent fraying. The cars are
suspended from it by ropes of equal length. Sufficient strength is given to the
hoop or frame to hinder its yielding though the ropes are placed far apart, thus
they need not be numerous. To avoid confusion they are not shown.
From the frame B ropes run (two are represented) through pullies on B to a
horizontal windlass in the car. By a little manual exertion applied to its spokes,
the acronaut has the means in all the balloons of bringing B nearer to A, thereby
diminishing the bulk of his balloon, and thus lowering its altitude. By slackening
the ropes the compressed gas re-expands the balloon and makes it rise.
B exerts automatically a constant slight pressure against the bottom of the
balloons however much they may contract or increase from alterations in atmos-
pheric density, for B follows its change, travelling upwards or downwards owing
to a weight attached to a pair (or pairs) of its ropes that a little exceeds the
weight of the lower half of the net and its belongings. This weight is made up
of things useful to the aeronauts, thus saving extra weight.
Numbers 1 and 2 are stops on B's ropes. It cannot get further from A than
stop No. 1 will allow, nor can it get nearer than No. 2 will allow, that being the
utmost compression to which it had been computed the envelope should be
subjected. On stop 2 touching a pulley a bell or alaruin warns the aeronaut that
the balloon is undergoing the utmost strain it can safely bear, and that he ought
to be thinking of his safety valves, although they would have been made to work
automatically, ever prepared to yield to a certain pressure of the gas.

page_text: It is assumed that the aeronaut when two or three hundred feet above the earth
would wish the envelope to be so inflated that B would automatically lie in the
dotted line M, Ml, midway between the limits in which it could travel, thus giving
the fullest latitude for expansion or contraction.
C, Fig. 1, is a hoop of similar size to A. Many short ropes of equal length (not
shown) connect the two hoops. By a few ropes of equal length the car is suspended
from C.
With large, deep, spherical balloons when the additional weight of C would be
of little consequence it would be found of much use, as it not only enables the
weight borne by A to be equally distributed among the many ropes running from
it to C, all kept clear of the net, but it also serves to keep B's ropes from
immediately converging to the car and fraying the net, as they would travel
through antifriction rings (Fig. 11) fixed in or on. C.
Some of the ropes from C which sustain the car could be united in pairs, and
could be so arranged that only the ropes from the several points of the junction
would be brought to the car. The more pairs that by good management could be
united the fewer would be the ropes brought to the car.
Fig. 5 shows merely the envelope of the navigating balloon fully inflated. Its
length is only about eight times its diameter; but it seems reasonable to believe
that a greater length will eventually be found advisable. Before it is filled it is
securely lashed at its extremities to a rope in its axis, which rope is of service
when the envelope is carried by hand, and also, in lifting the cage (not yet
described) in which it is kept. The net embraces it everywhere tightly, and, as
represented with the spherical balloons, it is possible that the rows should run
diagonally in the upper half, and in the lower half horizontally and vertically.
Fig. 3, when the envelope is empty the ends of the rope are firmly lashed to
the ends of A, which fits close to the envelope when it is inflated. The rope may
be strongly strained, as rectangular (or circular) brackets prevent the sides of the
frame from expanding or closing. The upper half of the net is merely laced or
fastened by lapping to A so as to be removable when required. As long as the
balloon floats horizontally that part of the net would be fully extended, even were
the envelope no more than half filled with gas. The net being thus fixed to the
frame, any tendency to the envelope assuming a deep form from the weight of the
car compressing its sides inwards is counteracted. Wire ropes running clear of the
envelope connect all the angles of the brackets on every side, diagonally as well
as directly, and are ultimately fastened to the extremities of the frame. Thus
they are retained firmly in position, all is made rigid, and admirable protection is
given to the engaged envelope. Some protection of this kind is essential, and it is
difficult to see how any lighter yet sufficiently unyielding could be suggested.
Fig. 6 is one of the rectangular brackets that, fixed at right angles to A, grasps
it in a firm embrace. Within it is seen a transverse section of the envelope and
of the frame B, also a transverse section of the frame A. In the wood work that
unites the bracket to A is a sheave at such distance from A that the suspension
rope travelling within it runs clear of the envelope however much it may bulge
out, as seen in Fig. 7. The laced frame B slightly presses against the envelope.
Fig. 7. In this bracket the frame B is shown compressing the envelope as much
as it is expected to bear without injury. The brackets would be made of a strong
yet light wood. To best meet the principal strains to which they would be
subjected, their upper and lower sides would be widest in a plane parallel to the
axis of the envelope, the vertical sides widest in a directly transverse section of the
axis. All edges would be sharpened to lessen resistance to wind.
Fig. 8 and 9 are circular brackets, which would probably be preferred to the
rectangular, as they would be lighter, more elastic, and present a smaller surface
to an opposing wind were it not for the expense often attendant on procuring
means for steaming the wood before bending it into form. In Fig. 8 B slightly
presses against the envelope. In Fig. 9 it is compressed as much as it is expected
to bear. The envelope being fixed high in the bracket allows of good space for the

page_text: frame B. The stay near the bottom much strengthens the bracket, but it is
questionable whether instead of making it a complete circle and having the stay,
it would not be better to bend the lower part into a chord in the line of the stay.
Steel is now cheap, and were it used for the circular brackets resistance to progress
would be much diminished. The projections p, p, &c., serve like the corners of
the rectangular frames to keep the ropes clear of the envelope.
Fig. 10 is the frame A and envelope shown where there is no bracket.. The
struts s, s, for the suspension ropes are inclined downwards to diminish strain
where attached to A. The sheaves in them are at the same distance from A as the
other sheaves.
The frame can be made very light, for it is only subjected to a strain when the
envelope is empty, which would seldom be on unlevel ground. Floating in the air
there would scarcely be any strain as the net would support it at the numerous
points of lacing. However long it has no natural tendency to yield or bend in
any particular direction, and although it is light the vertical support it receives
from the buoyancy of the envelope throughout its whole length allows the struts
to be far apart. Some bamboos, while possessing great strength and durability
combined with a straight growth, are so light that when procurable they would be
much used in forming the frame.
Evidently the expansion is very easily effected automatically in this balloon
(Fig. 3), as B, owing to its great length, presents a large flat surface to press
against the gas, and as its pressure is everywhere uniform, B will always remain
(although so long) in a plane parallel to A. From its great area so many square
feet are called on to act that the strain on each is trifling, therefore it (B) may be
light yet have superfluous strength. When the envelope is empty B by keeping it
off the ground preserves it from abrasion or friction.
There would be no plaiting of any portion of the body of the balloon on its
being compressed as it is cylindrical, but where the conical-spheroidal part meets
the cylindrical body there would necessarily be on compression a disproportionate
strain about the horizontal plane (where the bulging is greatest), and a crumpling
of the envelope underneath. That part therefore would be strengthened by an
extra covering, or the bulging part might be supported by a band, its ends being
fastened to the frame. Should there be a leakage it is more likely to occur at the
lower part of the balloon than the upper owing to the wear, however slight,
consequent on the frequent change of form. This is fortunate, as the upper would
at once become a useful parachute.
Fig. 4 is comparatively speaking a short navigating balloon formed on the same
principle, but as if balloon, Fig. 2, lay on its side narrowed and deepened. Con-
traction is effected, as in the other balloons, by the aeronaut being able to make the
hoops A, B, approach each other. The pressure of the gas separates them.
A, C, E, G, F, D, B, are flat hoops within the envelope; they help to keep it
extended; they are strengthened by a few struts in the line of the diameters. To
prevent their fraying the envelope their exterior surfaces are a little convex, and
are covered with some soft substance. Broad hempen bands cover the loops
outside the envelope.
PP, is a long round pole, probably formed of more than one bamboo. The
central hoops are fastened to it but not rigidly. Antifriction rings are firmly
attached to the bottom of the two outermost hoops at both ends of the balloon.
The pole passes freely through the rings. When the envelope is inflated it supports
the pole, while the pole gives firmness to the envelope.
H is a long pulley with two sheaves revolving in the same plane.
1, m, n, o, are light rings (possibly antifriction rings) through which, as well as
the pulley, ropes pass to the acronaut that give him the power of diminishing the
bulk of the balloon. The rings are firmly attached to projections on the hempen
bands. Of course there are similar ropes on the other side of the balloon, lest
the aeronaut's releasing the tension of the ropes by which he brought A and B
nearer to each other should not always suffice to make the gas afterwards fully

page_text: separate them (however well all the antifriction rings on the hoops and pole
might act), a cylindrical spiral spring between the extremity of each pole and its
adjacent hoop, of a retractile power that equals the computed resistance, friction,
and the weight of the ropes, makes A and B on all occasions work satisfactorily,
even automatically following the natural changes in the bulk of the gas consequent
on alterations in temperature. The aeronaut would always have sufficient power
to overcome both the resistance of the spring and the gas. The two cords from A
and the two from B are respectively looped together, and, were it considered
desirable, could be united and brought to the aeronaut as a single cord.
The envelope is closely embraced by the usual net. The leading part of the
balloon terminates in a shape approximating to a cone, and is well stiffened by an
.extra covering with cane work intervening.
The suspension ropes to the cars are so attached to the net that they hang from
a little below the horizontal mid-zone of the balloon; lest all should not be strained,
their ends might be elastic, especially those converging from the extremities of the
envelope when the hoops A and B are drawn together...
Instead of contraction or expansion being managed from the ends of the balloon,
the change could be effected in its middle by the central hoops having the pullies,
as shown in Fig. 1. To travel freely along the pole every hoop would require an
antifriction ring, or two poles might be used, the end part of one passing in a
parallel and vertical plane through antifriction rings fixed to the end of the other.
A half of the balloon would be attached to each pole. Dragging ropes would be
brought to the acronaut both from the central antifriction rings and the central
hoops.
It cannot be thought that balloons of Fig. 4 kind could be made as long as the
one represented in Fig. 3, which could be constructed of almost any length; but
though not possessing the capabilities of extensive application expected from that
form, the plan (Fig. 4) seems simple and the working gear light and cheap.
Fig. 11 is the antifriction ring just named formed of sheaves (of pullies) so
arranged in a circle that the rope running within it is ever in contact with a
grooved rotating surface; in other words, a circular multisheaved pulley, for the
sake of lightness all made of wood, excepting the axles, and none larger than
necessary.
In every thing the builder's motto will be "lightness with strength," and his aim
and difficulty will be to make all work in harmony; no part being unnecessarily
strong, in other words unnecessarily heavy; all presenting little surface to an
opposing wind.
With navigating balloons it is for many reasons best that the suspended weight
should be divided between two cars, one for propulsion the other for cargo.
The suspending ropes to the propelling car, all of equal length, might with safety
be few in number and be attached at wide intervals in pairs to the car in planes
at right angles to the long axis of the balloon, thus constantly retaining the
parallelism of the car with A however much one might get in advance or fall in
rear of the other. When flying rapidly through the air the car would get so near
to the balloon and be so much in front of the centre of buoyancy that its suspension
ropes would more approach a horizontal than a vertical direction, which shows that
no suspension ropes could be brought from the ends of a long balloon to that car
as they would never be equally strained except when the whole system was at
rest. A stayed bow-sprit and a stern-sprit (possibly two of each would be best)
would be required to increase the length for affording points of attachment.
However light the car may be built its sides should be stiff to allow of points of
suspension being far apart. Thwarts would prevent their expanding or closing.
Manifestly the cars of all navigating balloons should be long. The frame A would
be so stiff that the propelling car could be hung next to the balloon by but a few
ropes from A, so disposed that they would not interfere with the action of the
propellers whatever might be their form or size.
Of the weight to be carried the more that could be placed in the cargo car the

page_text: longer the suspension ropes, and the more they converged to a point (the centre of
gravity being directly under the centre of buoyancy) the more easily would the
ascent at starting be effected, and the more would the weight tend to give steadiness
to the whole system, although the less would be the difference of strain on the
foremost rope and the aftermost when the axis of the long balloon deviated from a
horizontal plane, also the less detrimental to the maintenance of the position would
be any shifting of the load in the car. The position of the cars in the system might
be reversed, but it seems reasonable to place the dragging power near the centre of
the load unless the cords of the cargo-car should interfere with the working of the
propellers. For the aeronaut to have perfect control over the altitude of his balloon
it is evident that the car (which is the fulcrum) must possess sufficient power, that
is, sufficient weight with the aid of the pullies after all stores of provisions, &c., are
consumed, to compress the gas to the dimensions that will bring the nets together.
Weight beyond that is disadvantageous. To have sufficient weight it may at
times be necessary to form a connection between the cargo car and the driving
car.
From the pressure, though slight, always exerted by B the gas within the
envelope may, as a rule, be regarded as stationary, but lest there should ever be a
cessation of that pressure at a moment when the balloon was not quite horizontal
it would be judicious to have it divided transversely in the middle by some flexible
gas-tight material. This would tend to restore the horizontal position, as the evil
caused by the gas rushing to the end of the half of the balloon that rises would be
counteracted by the rush of gas to the centre of the other half. The greater
the velocity the less is the chance of any disturbance through deviation from a
horizontal plane. The safety-valve of each half might be fixed close to the partition,
and the cords from them be united to enable the aeronaut to operate sinultaneously
and equally on both. In a balloon of extreme length more than one partition
would be advisable. For the sake of easy arrangement, and to keep the valves
near the aeronaut, it is suggested that they (v, v, Fig. 3) might be at the bottom
rather than, as usual, at the top of the envelope.
During flight the gradual rising or sinking of the propelling car would be
governed by a wide horizontally hung tail as seen in the fish torpedo, or (which
would give a better purchase on the air) by having a flat thin plane on each side
of the car, hinged on one central transverse horizontal axle with spokes. The
plane might be a laced rectangular frame with a light yet strong close wove
linen material stretched across it. Both planes would be simultaneously moved by
the aeronaut. The extremities of each plane would work in the arcs of circles
distant from the axle. To minimise the changes of inclination of the planes from
their horizontal position (which necessarily diminish speed through the increased
resistance of the air on the planes when inclined) the aeronaut would have
Both means of
recourse to B as a means of increasing or diminishing his altitude.
guidance would often be simultaneously used. In a very long car it might be
judicious to have a pair of planes at both ends rather than to increase the fore and
aft breadth of a single pair, thus following the principle seen in windmills where
the area of canvas effects most when divided into long narrow parts.
Inflation could be conveniently managed through a long, flexible pipe, its nozzle
being received where the end of the envelope is attached to the rope lying in its
axis.
With great velocities it is evident a strengthening of the material at the bow or
some kind of protection would be necessary to prevent the pressure of the wind
from compressing the gas and altering the shape of the bow, thereby giving
uncertainty to the direction and retarding progress. Such protection would be
much required when the balloon was at anchor in a gale, the only time when
mischief from a high wind need be guarded against. The vertical deepening of
the frame at the bow and bringing it to a sharp angle to cut through the air
would make a protecting shield, or there might be an attached stayed shield of
light wood, or a frame covered with a light strong canvas, as shown in Fig. 3.

page_text: Strengthening the bow by an additional stiff covering, as recommended for balloon
Fig. 4, would destroy the flexibility necessary for expansion and contraction to be
effected automatically.
The difficulty experienced in anchoring spherical balloons would not be found
with a navigable one, as its sharp head would be brought into the wind, and the
auclior dropped exactly where desired.
As navigating balloons are not required to rise and fall in order to seek for
suitable currents of air there is comparatively little call upon their compressors, and
in every respect, excepting the first outlay, they seem superior to the spherical.
Even their great length, which looks objectionable, is in their favour, for the longer
they are the stronger they are. This may at first seem paradoxical, but given a
certain volume of gas to be subjected to much pressure the longer the body con-
taining it the greater is the pressure it will bear. This is evident the moment it
is called to mind, that made of the same thickness of metal the less is the diameter
of a tube the greater is the bursting strain it can sustain with impunity. Further,
the longer the envelope the more will be the material used, therefore the larger
will be the nuniber of meshes employed in bearing the bursting pressure, also in
sustaining the weight, and consequently the less the strain on each individual
inesh. Length does not mean weakness of form, for when the balloon is floating
in the air all parts are at all times equally sustained. It is never supported like a
ship in a storm by a surface of alternate depressions and elevations.
Economy is
consulted in having length, for every increase in length gives more than a
proportionate gain. Every increase diminishes the weight that every cubic foot of
gas will have to float, for added length augments so little the resistance to progress
that the weight attendant on obtaining further propelling power is not required.
Hence diameters being similar in three balloons, one of double the length of the
other two would not be required to sustain more than would be demanded of the
two, thus effecting a great saving in cost and in space for cargo. It is true that
such length would be very objectionable were the balloon often laid on uneven
ground, but it is presumed that as a rule it would remain when not on a voyage
riding at anchor in its natural element, the air, and only be brought occasionally
into dock to .be overhauled and repainted or dismantled, and "laid up in
ordinary."
With regard to spherical non-navigable balloons as carriers there is the same
advantage in having them large as in having ships of large tonnage; for the
contents of similar bodies being as the cubes of similar parts, while their superfices
are as the squares of similar parts, if in two balloons of similar forin one be double
the depth of the other, the carrying power of the larger will be four times that of
the smaller, while the quantity of expensive material and net required for the
larger will only be twice that required for the smaller. For let 4; be the depth
of the larger balloon, 2x the depth of the smaller balloon, the gas (buoyancy) in
the larger will be to the gas (buoyancy) in the smaller as 43 to 23, that is, 8 to 1,
while the superfices (material, &c.) of the larger will be to the superfices
(material, &c.) of the sinaller as 4 is to 2, that is, as 4 to 1. This means that
in building a balloon we obtain at only twice the cost four times the carrying
power.
"
Every material employed in the construction of the balloon and all its belongings
should be of the lightest kind compatible with strength. All cordage, &c., should
be waterproof, to prevent anything ever becoming sodden and weighted with
moisture. Weights being equal, wire rope of all sizes is said to possess twice the
strength of the best hemp cordage, and to be quite as pliable; being thin it would
have little hold of the air. Principally to prevent the shifting of gas in long
navigating balloons at every departure from the horizontal position, they should be
constantly subjected to slight pressure, in order to keep the envelope extended.
Although in long balloons of little diameter the net at all times by its tight embrace
gives immense support to the envelope (for however much contracted by pressure
there is no plaiting), the material of which it is formed should be the best that

page_text: could be manufactured, soft, pliable, and light, yet strong. The chief difficulty
would be to render it impervious to hydrogen gas. A material well adapted for
coal gas might be quite unfitted for hydrogen.
It is certain that the ends of the envelope could be so supported or strengthened
that they would resist great interior pressure, and that the cylindrical part could.
be made to withstand any amount of bursting strain were the meshes of the net
small and the cordage strong, but the resultant weight would be quite detrimental
to buoyancy. Supposing it to be ascertained by experiment what is the greatest
bursting pressure per square foot the best material for the envelope is capable of
sustaining, and that it be settled what is the greatest pressure per square foot that
could ever be demanded of it, the question arises, what is the greatest area that
could with safety be given to the material within each mesh? The answer
determines the greatest size that could be given to the meshes. The better the
material the larger the meshes; the less their number the lighter the net. Then
comes the question, whether there are advantages in a diamond form of mesh that
compensate for the loss of the greater space embraced by square meshes? Then
how thin (how light) might the cord be made without risk of breakage? Much,
of course, depending upon the diameter of the balloons, as although the strain on
the envelope-material is unaffected by length of diameter (the size of the meshes
supporting the several areas of material in no way depending upon it) the strain on
the net increases as the diameter increases, a fact that argues in favour of long
narrow balloons, as the thickness (the weight) of the cordage of which the net is
formed can be proportionately diminished. Then how could fraying of the
envelope be best prevented? It would be lessened with the net formed of well
shrunk webbing instead of cord. It would hold little wind, and form no receptacles
for the lodgment of snow. Made of silk it would be light and strong, but
expensive. The broader the webbing the less required, as the more the material it
would cover and protect from strain. Were the meshes only fastened together at
the centre of the crossings there would be free play for the edges to give and take,
yet the whole would lie smoothly, as the envelope when inflated would always be
fully expanded. A strand or two of clastic twine running across the several areas
from the edge of the webbing to the opposite edge would prevent their curling up.
There is another question, whether any and what extra strength should be given
to the upper portion of the net, owing to its having to sustain the weight of the
cars as well as the bursting strain? The inconvenience attendant on attempting
such an arrangement would probably outweigh any gain.
It is undeniable that as far back as 1852, when the power of steam engines
compared with their weight was much less than in those recently made, M. Henri
Giffard, a very talented engineer, proved that he had adopted a sound principle of
propulsion for ballons, and one which only required further development to show
that rapid travelling in the air against an adverse wind need no longer be regarded
as a visionary object. With merely a three horse-power engine, and a screw of but
10 feet diameter, in a ballon inflated with coal gas, of a length not four times that
of its diameter, he obtained a velocity exceeding five miles an hour, and found
that his air vessel was quite obedient to the helm.
During the siege of Paris, at a moment of great excitement and haste, M. de Lôme,
by the clever plan devised by General Meusnier of inserting in his balloon a bag
inflated with air (which the aeronauts from the car could pump in or out at
pleasure), was able to alter his altitude without altering the bulk of the balloon by
increasing or diminishing its weight. As air was forced in to increase weight the
density of the gas was increased, yet he lost none, and the envelope withstood
successfully the strain, but the method was most inconvenient. No ingenuity
could make the plan self acting, and it was adverse to rapid progression. Moreover,
instead of employing steam he took relays of men whose weight must have been
most detrimental; but even so, the propellers worked by their efforts being far
larger than M. Giffard's, a greater speed was obtained, and the rudder acted most
satisfactorily.
•

page_text: These indisputable facts are very encouraging. When we consider the lightness
combined with firmness that skilled workmanship could give to a cage of great
length which would effectually protect the envelope, the vast strides science and
ingenuity have recently made through the new properties given to steel in
decreasing the weight of steam engines while adding to their power, the great
saving that has been effected in the consumption of fuel, as well as in the demand
for water, owing to constant recondensation of steam, the great improvements
making in hydraulic propulsion by turbines, whereby balloons may possibly some
day be propelled by air on the same principle, to say nothing of the prospect of an
available motor in electricity; when we consider all this it does not seem pre-
sumptuous to believe that with the mechanical aids now available the exercise of
but a small portion of the talent that has rendered traffic by land and by sea such
a marvellous success (a success the wildest imagination could not have conceived
practicable half a century ago) should soon be able to effect such further improve-
ments as will make expeditious aerial navigation a realized fact. No transport
could be so rapid nor so cheap; no mode of locomotion could be subjected to
fewer accidents or less wear of material, for when carried along by the violence.
of a hurricane the propellers would not encounter the slightest alteration in
atmospheric resistance nor would the aeronauts be more disturbed than if floating
in a perfect calm.
Having now described the nature of my Invention, and in what manner the same
is to be performed, I declare that I claim the making balloons rise or sink without
the loss of either gas or ballast, substantially by the means described in this
-Specification.
In witness whereof, I, the said William Nelson Hutchinson, have hereunto
set my hand and seal, this Seventh day of October, in the year of our Lord
One thousand eight hundred and eighty one.
W. N. HUTCHINSON, (L.S.)
General.
Wellesbourne,
Bideford.
P.S. The lightness of hydrogen might be combined with the compressibility of
coal gas by a horizontal diaphragm near the mid axis of the balloon, or by having
two balloons in close contact, hydrogen in the upper, coal gas in the lower.
W N HUTCHINSON