IMPROVEMENTS IN AERIAL NAVIGATION
Year: 1854

page_text: LETTERS PATENT to Benjamin O'Neale Stratford, Earl of Aldborough, of
Stratford Lodge, in the County of Wicklow, in Ireland, for the Invention
of "IMPROVEMENTS IN AERIAL NAVIGATION."
Sealed the 27th June 1854, and dated the 30th January 1854.
PROVISIONAL SPECIFICATION left by the said Benjamin O'Neale Strat-
ford, Earl of Aldborough, at the Office of the Commissioners of Patents,
with his Petition, on the 30th January 1854.
I, BENJAMIN O'NEALE STRATFORD, Earl of ALDBOROUGH, of Stratford Lodge,
in the County of Wicklow, in Ireland, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN AERIAL NAVIGATION" to be as follows:-
First, the construction of wings in such a manner that they compress the
air by percussion and force it under the concave part of each wing, currents
of air being also impelled towards the same parts by fanners, which act on the
same principle as that on which I believe the alæ spurice or spurious pinions
of birds act; the centre of pressure caused by their combined action, and also
by the current or currents of air which pass under the wings, in consequence
of the progression of the aerial machine or vessel and the action of the wind,
creating a support under each wing, and consequently at each side of the
weight to be raised or sustained. The air is also compressed under the weight
itself, but I believe that the mechanical force acts more especially at each
side. I effect this object by raising the wings slowly, and by making use of

page_text: the advantage thereby obtained to accumulate force by every available means
according to the size of the aerial machine or vessel; a combination of springs
being forced upwards as the wings are raised, the reaction of which causes
them to perform the stroke downwards, which is as nearly as possible instan-
taneous, the only diminution of velocity arising from the resistance of the air
below on which they act, and from the unavoidable friction of the cords and
machinery, which is reduced to the lowest possible point by all known
means suitable to the circumstances; the extremities of the wings, and also
the alæ spuriæ striking the air by distinct actions, in addition to the impulse
of the entire wing of which they form parts, and with which they necessarily
move in a manner as nearly as possible similar to that in which I believe a
bird's wing is moved, the carpus, metacarpus, and phalanges to which the
primary feathers are attached, being capable of acting, as I believe, like the
human hand and fingers, independently of the humerus and cubitus, either
simultaneously with those parts, or otherwise; the alæ spuriæ, the position of
which is somewhat similar to that of the human thumb, having also a distinct
action, and, I believe, a very important one in the bird's wing. I cause the
extremity of the wing to perform the stroke at the same moment that the
entire wing strikes downwards, this combined action forcing the air much
more effectually under the wing, and also under the weight to be raised or
sustained, more especially as the extremity of the wing would otherwise be
bent upwards during the stroke by the compression of the air underneath; but
it may also be made to strike during the rising of the wing. I prefer arranging
the mechanism so that it shall strike once, twice, or a greater number of times
during the rising of the wing. The alæ spuria must always strike during the
rising of the wing, but it also strikes simultaneously with the stroke of the
wing. The details of the arrangement are represented in the accompanying
Drawings. When I speak of raising the wings slowly, I mean in comparison
with the downward stroke. I make use of the term percussion to express the
instantaneous action of the wings in the stroke downwards, as distinguished
from that of ordinary machines. I believe that a bird is sustained in the air
by the excess of pressure against the lower surface of the wings and body
beyond that on the upper surface, but although the density of the air under
the entire of the lower surface must be greater than above, I consider that the
principal force is derived from the centre of pressure occurring under each
wing precisely at that point where it acts with the greatest mechanical
advantage, and I believe this to be one of the essential points in which the
principle of flying or sustaining and moving a body in the air differs from
that of floating or moving through the water, and I believe that each succes-

page_text: sive stroke of each wing creates to a certain extent a fresh "point d'appui "
or support by the compression of the air under the wing and under the body
of the bird, the strokes of the alæ spuriæ producing the same effect in a
smaller degree, and the current or currents of air produced by the progress of
the bird contributing to the same object, and the wind also frequently assisting.
I believe that some birds more especially take advantage of the wind, using
their wings to a certain extent like sails, and by this means.flying with less
labour and also with less noise, as seems to be the case more particularly with
owls; but I believe that the real supports or at least the principal points of
support which sustain the bird, are always under those parts where the centre
of pressure occurs under each wing. I believe that if the density of the air
under these points could be ascertained while the bird is flying, it would be
found sufficient, according to clearly defined scientific principles, to support.the
bird; and, I believe, that both the formation of the bird's wings and their
action, and also that of the alæ spuriæ, tend to concentrate the force of the
pressure precisely under those points where the greatest mechanical advantage
is derived from the support; for although the arm, as it may be termed,. of a
bird's wing, or that part composed of the bones and sinews, is in advance of
the centre of gravity of its body, the centre of pressure occurs, as I-believe,
under the hollow part of the wing behind the arm, and I believe that a line
drawn through the centre of gravity, and across the body of the bird at right
angles, with one drawn also through the centre of gravity from the head to the
tail, would pass precisely through those points under the wings where the
centre of pressure occurs under each. I believe that the alæ spuriæ; or alulæ
spuriæ, as they are sometimes. termed,, although some ornithologists seem to
consider them as merely covers. for the. basis of the primary quills, really act
as fanners to the wings, and perhaps. even to a certain extent as propellers.
I believe that the primary feathers of the wing may be considered as acting the
part of oars as far. so regards propulsion;. but that they at the same time com
press the air, and force it: under the hollow parts of the wings, which latter
are, as I believe, principally useful as parachutes containing the air so impelled,
that is to say, sufficiently so for the purpose, although all parts of the wing
assist to a certain extent in performing the stroke when the entire wing, iş
moved from the shoulder. Birds appear sometimes to strike with the back part
of the wing when rising, but this is not the ordinary action of the wing while
flying, and I consider the principal office of this part is that of a parachute.
I, however, believe that the back part of the wing when in certain positions
also acts the part of a sail to a certain extent, and the mechanical wings as I
form them can also be made to serve a similar purpose. I consider that the
0

page_text: failure of the attempts hitherto made to raise or sustain a body in the air by
means of wings, are principally owing to ignorance of the fundamental prin-
ciple on which alone wings can be made available for the purpose, and that
by which they perform this office for the bird, that is to say, by impelling the
air under the wings and under the weight to be raised, instead of from it, like
the oars of a boat or the paddles of a steamer. I consider that the stroke of
the wing would not be efficient if it were not raised more slowly than it strikes
downwards. It is well known that the resistance of the atmosphere to any
surface is in proportion to the speed with which the surface is moved against
it; and in addition to this a comparatively slow motion of the wing while rising
permits the current or currents of air passing underneath more effectually to
fill the concave part; when the wing is raised to the extent required, it is then
caused to strike downwards with an instantaneous motion before the air has
had time to escape, so as to speak, from the stroke. I consider that it is only
an alternate or reciprocating motion that can produce this effect, and that a
continuous circular motion like that of paddles, or even the action of a screw is
altogether unsuitable, and incapable of producing the necessary effect on the
air. I believe that the effect is produced in a great measure by the sudden
or instantaneous change in the direction of the impulse to a direction directly
opposite, which greatly increases the resistance, and different currents of air
being impelled towards the same points, or passing towards those points by
reason of the progress of the bird or of the machine or vessel, cause violent
compression at those points. As regards the steering, I consider that it de-
pends chiefly on a principle which does not appear to have been ever acted on
or even defined theoretically, at least with sufficient distinctness, although
some of the facts, which I consider afford proofs of the principle, have been to
à certain extent remarked, which are, that all birds possessing great powers of
flight evidently fly with very little labor or muscular exertion, and that some
fly almost always with a sailing motion and little noise, and with one wing
more elevated than the other. I believe that this faculty depends on a prin-
ciple which all birds avail themselves of, more or less, in guiding and especially
in turning themselves in the air. I believe that when the wings are in this
position, that is, one wing elevated and the other depressed, that both wings
together act to a certain extent on the principle of an inclined plane placed
across the body of the bird, its descent on the side of the depressed wing being
prevented by a slight action of the wings or of the spurious pinions, by means
of which the air underneath is compressed and caused to act against the under
surfaces as the wind acts against sails, and the bird is even enabled to set
them, as it were, to a certain extent against the wind when it blows from an

page_text: unfavorable point in consequence of their form & their stiffness, which enables
them to preserve that form independently of the wind, which when it impinges
on the upper surface, glides off to a certain extent, comparatively at least, and
is impelled under the concave surface by the action of the wings or of the
spurious pinions, and by this means the bird is impelled in the direction it
desires. I am aware that the principle of the inclined plane has been fro-
quently suggested as suitable to aerial navigation, but not, as I believe, in a
manner similar to that which I have described, and I only claim it when
applied in the manner I have mentioned. If the action of a bird's wings be
remarked when turning or suddenly changing its direction in the air, it may
be perceived that it raises the wing on the side from which it desires to turn,
and commonly strikes with that wing, at the same time holding the other wing
in a horizontal position, or inclining it slightly downwards, or drawing it back-
wards, or partially closing it to a certain extent, according to circumstances;
and it is evident that this principle can be applied to resist or modify the effect
of an unfavorable wind, which would otherwise drive an aerial vessel out of
its course, the action of the wing on the leeward side being capable of pro
ducing an artificial current to counteract or modify the effect of the wind
on the windward side. This is only an application of the well known
principle of the composition of forces which will determine the course of
the vessel in an intermediate direction between the two impulses. When
the wind is not too directly opposed to the vessel's course the desired point
may be reached by working both wings on a principle similar to a certain
extent to that on which a boat is rowed across a river where there is a
strong current, but in no case having any analogy to the tacking of a sailing
vessel, in which latter case the action of two separate elements at the same
time produces the effect. But I consider that it will generally be much more
suitable during a strong galo to work the leeward wing only, the windward
wing being held steadily in a horizontal position or slightly inclined downwards
if the wind be violent or very much opposed to the vessel's course; but when
the wind is on the quarter (to use the term common in navigation) and not
too violent, I consider that the windward wing may be raised and set steadily
at any suitable elevation, and by this means advantage may be taken of the
impulse of the wind, the leeward wing being worked at the same time, so as
to impel the vessel in the desired direction, or it may sometimes be advisable
to work the windward wing gently or cause it to perform half or quarter
strokes, working the leeward wing at the same time with its full force. I
.consider that an aerial vessel will arrive much more quickly at its destination,
independently of saving the wear and tear of materials, by proceeding on this

page_text: principle; than by labouring in direct opposition to the wind, even supposing
the latter course to be practicable, as more will be gained by increasing the
speed than will be lost by increasing the distance. In a calm, it will of course
be-
necessary to work both wings alike or nearly so. As regards the principle
of rising or descending, in order to attain a position where a favourable
current may be found, the greatest facilities are afforded by my system, by
which I can cause the vessel to rise or descend at pleasure without loss of
either gas or ballast. The particulars as regards the means used for this purpose
are described under the second and third claims. But this facility does not
supersede the necessity for finding means of guiding the vessel in contrary
winds, as a wind exactly favourable can seldom be calculated on for an entire
voyage, or at least it could not suffice to bring the vessel to the precise point
required, and I consider it almost always advisable to ascend more or less
against the wind or with the vessel's head to the wind; as the wind elevates the
vessel more effectively when acting on it in this way, and the danger of being
carried forwards with too great speed or violence is also avoided till all
obstacles are fully cleared, which might otherwise cause the destruction of the
vessel; as so frequently occurs to ordinary balloons before they attain a suffi
cient height to surmount them. When the vessel has arrived at a sufficient
èlevation I wind gradually into the desired course. When descending, especially
during a strong gale, I turn the vessel's head to the wind in order to avoid
being impelled forward during the operation of effecting a landing; and for
this object also it is advisable to describe a gradual curve, or in some instances
a succession of curves, as birds very commonly do before alighting. I believe
that birds make use of the tail as an inclined plane by elevating one side or
the other, the inclined plane acting sideways as in the case of the wings. It
is well known that birds make use of the tail when rising or descending, but
it does not appear to have been discovered, or at least does not appear to
have been clearly defined, that they also guide themselves in a lateral direction
by elevating one side or the other, and this motion of the tail may also be
perceived when they are turning or circling; they appear sometimes to move
the tail also sideways from the base, but I believe that a change of direction
is effected principally so far as the action of the tail is concerned, by using it
as an inclined plane in the manner I have mentioned. I believe that birds
guide themselves chiefly by means of their wings, but I consider that it is by
using both the wings and tail as inclined planes on the principle that I have
explained, that they are enabled to fly with so little effort as the greater
number of birds do, and I consider that the application of this principle
supplies. one of the principal means by which aerial-navigation may be accom-

page_text: plished without that enormous exercise of power which seems hitherto to
have. been considered necessary, and which it has commonly been supposed
impossible to unite with sufficient lightness of material.. I consider it essential
that the weight to be raised should be placed on springs against which the:
bases of the wings and also of the tail, should press upwards, one part being
pressed upwards by the action of the wing while rising, and the other part
being so pressed while it is performing the stroke downwards, these springs,
being also so constructed and arranged that they may exercise a certain
upward pressure leven during the recoil. Both the wings and tail act on the
principle of the lever, and the centre of gravity of each lever is at the opposite
side of the fulcrum or pivot from the weight to be raised or supported.
Figures 1, 2, 11, and 15 shew the lower surfaces of different modifications.
of wings.
Figures 1.and.11 shew also the lower surface of the tail or rudder in com-!
bination with the wings. In the latter figure an additional sail or what may be
termed a second rudder or tail is represented, which is placed over the first,:
but its base is set under springs, in a manner similar to the lower 'one. ‹I
consider this arrangement the most perfect, but the upper rudder or tail is not
absolutely necessary; both of these can be made to act as inclined planes either,
laterally or vertically, and the lower one or even both may be made to strike,
downwards against the air when rising, and so increase the ascensional power;
by compressing the air underneath, as I believe birds commonly do, especially,
pigeons. It is evident that, even when an aerostat or envelope containing gas or
rarified air is used, it is nevertheless advisable to increase the ascensional:
power independently of the aerostat by all available means, as by so doing the
size of the latter and the consequent resistance of the atmosphere to its pro-
gress in any desired direction may be diminished. I consider that the
mechanical action of the bases of the wings and tail against springs will
contribute very materially to this object in consequence. of the elastic nature
of the atmosphere, which makes it essential, as I believe, that a springing.
motion should be communicated to the body to be raised, which I consider.
will have much effect in counteracting the tendency to fall during the.
intervals between the strokes of the wings; and even the variable action of
the wind, which appears to present one of the greatest difficulties, but which
seems really to be caused only by the susceptibility of the atmosphere to be.
acted on by apparently inadequate means, renders this arrangement essential,
as I believe, in order to sustain the body during the lulls which commonly
intervene between gusts of wind, as well as between the strokes of the wings...
I also consider that the peculiar nature of the atmosphere requires that it:

page_text: should be acted on by an elastic force. In very small machines intended only
to be used by a single person, I term that part which immediately sustains
the person and apparatus, the seat or saddle, in large vessels I term this part
the hull of the vessel. The frame work of the wings and also that of the
rudder or tail is formed principally of a species of very light canes or reeds
which grow on the banks of the Mediterranean, where they are well known
and are commonly used by the peasants as fishing rods. I strengthen them
by means of prepared ox muscles or sinews, called in France "nerfs de boeuf;"
they are well known in Paris, where they are commonly used by coachmakers
and mechanics. They should be stretched evenly along the canes or reeds, and
attached to them by means of glue or copal varnish or other adhesive sub-
stance; they should afterwards be covered with silk or other light material
and varnished. When the wings are of a large size these canes or reeds may
be further strengthened by boring them and filling the hollow part with
caoutchouc in a liquid state, and then inserting a steel rod in each, or these
steel rods may be attached to the outside. These steel rods should be tempered
like fencing foils, and I prefer a form in most instances nearly approximating
to that of a fencing foil. In some positions, however, some parts of these rods
require to be flatter, in proportion. The canes used for the fore part of each
wing should be stronger than those used for the hinder part, and when the
wings are of a large size bamboos may be used instead of the very light canes
or reeds I have mentioned for the forepart of each wing. a, a, Figures 1, 2,
and 15, are boxes or sheaths containing cords which may be of good ordinary
material, but I prefer caoutchouc prepared so as to have the greatest elastic
force possible, but I do not claim any improvement as regards the preparation.
These cords are twisted round the stems of the wings and the bases of the
lateral shafts of the tail in a manner common in workmen's tools, especially
small frame saws. The stems of the wings which are formed of either canes or
bamboos or wood, or a combination of these strengthened by steel rods, are
attached by means of these cords to the lower part of the seat or hull of the
vessel, and they are set in such a manner that they spring strongly downwards
when not drawn in the opposite direction, the parts b, b, acting as the short
arms of levers, and pressing upwards against springs when the wing strikes
downwards, and the parts b', 6', pressing upwards against other parts of the
springs when the wing is raised. These springs are formed of thin flat pieces of
elastic wood strengthened by the prepared ox muscles or sinews already men-
tioned, with their flat steel springs wound or coiled round them. The extremities
are bent upwards and lapped one over the other at top, where they are
attached to the framework of the seat or of the hull of the vessel, and I

page_text: consider it advantageous to stretch a band of elastic caoutchouc round each
of these springs. The principle is the same as regards the tail, but the
modification slightly different.
Figure 3 is a side view of one of these springs. They are set obliquely, the
upper part being inclined inwards, and in all positions in which it is practicable
I prefer inclining them also forwards as much as possible in order that the
pressure may act as much as possible in that direction. d, Figure 3, is a steel
spring, or combination of springs, which presses downwards against that part of
the stem of the wing indicated by the letter b', so as to increase the force of the
stroke of the wing, and a similar one presses against each of the lateral shafts
of the tail. The canes or reeds or bamboos, which with the steel rods and their
covering form the wing, are attached to the stems; these and also all other
parts that require it are strengthened by the prepared ox muscles or sinews
already mentioned. I term the principal bamboo or cano of each wing with
its oar, the beam, and the others, the shafts. I apply the former term also to
the principal oar in the more complicated form of wing, although in this latter
form it is not attached to the bamboo or cane. I term the parts e, e, the oars;
they are formed of elastic wood strengthened by steel rods or foils. I have
represented the more simple form of wing in combination with the ærostat,
Fig. 11, as I consider that from the simplicity of its construction it will be
found most useful in practice for crostats generally, except when they are of a
very large size, in which latter case the form of wing represented in Fig. 2,
may be advantageously used. Its construction is more complicated, the oars
being so arranged that they can be drawn backwards when desirable; having
their bases set on the pivots or joints f, f, they spring forwards when liberated
by the reaction of the springs g, g, which are placed between the oars, one end
of each spring being attached to the oar in front, and the other end to the oar
behind it, and also by the elastic reaction of cords or stays of elastic caoutchouc
or other clastic material, which are drawn over pullies or small wheels placed
in the fore part of each wing, and passing from thence to the hull of the vessel.
The number of the springs g, g, may be increased, if necessary. The oars are set
with an inclination downwards in such a manner that the extremities spring
downwards when not drawn in the opposite direction. The arrangement repre-
sented in Fig. 1, is adopted in order to admit of the wings being closed, or as
nearly so as possible, when the person is not using them, so as to permit him
to walk with as little inconvenience as possible before rising and after descend-
ing. This is not necessary as regards the wings intended to be used with an
erostat, and in the latter the arrangement for partially closing the wings has
reference to the more perfect steering of the vessel, and effecting the descent

page_text: with greater facility, or impelling the vessel forward at any particular moment
with the greatest speed possible; these wings may even be made to close
partially after each stroke, if so required, as birds commonly do, but I no.not
consider that this will be found necessary. in practice. The more simple form
of wings represented in Fig. 11, may be used with an apparatus adapted to the
use of a single person; but it has not the advantage of the capability of being
closed at pleasure. The tail or rudder may be made to close in armanner
similar to the tail of a bird, and the angles of inclination of the bases of both
the wings and tail-may be altered by means of adjusting screws or other
convenient arrangement, when it is considered advisable to form these parts
of the framework to which the springs are attached in such a manner as to
admit of this alteration being. made at pleasure; but this is not absolutely
necessary, and the more complicated arrangement will of course be attended by
increased expense. The Figures in which the ærostat is represented are on a
smaller scale than the other Figures; as the Drawings would otherwise be
required to be of a very large size. The direction of the stroke of the wing
may be more or less oblique, but it must always direct the air under the weight
to be raised or sustained. The shorter 'oars e¹; e¹, are set in front of the beam or
principal oar in order to give a form slightly curved or falcated to the fore part
of the wing. similar to that of most birds; by means of these the foremost edge
can also be made: sharper, without sacrificing strength, and the cords or stays
which serve to keep the wing expanded by, drawing the beam forward are
passed over these: The same letters indicate similar parts of the wings in all
the Figures in which the wings. are represented. The part his concave, but it
is most so in the middle and hinder part of the wing; this form is given to.it
by. bending the canes or reeds (and also the oars in a slighter degree) in this
part, or this part of. the shafts may be formed of curved pieces of wood, the
parts of the stems b', 6','are also curved; the part:i', ', is flat or nearly. so.
Those parts of the canes or reeds with the extremities of the steel rods or foils
which form the framework of this part, are drawn upwards by cords, indicated
by the letter j; Fig. 4, to the arched part of each shaft,, being set with their
points or extremities inclined downwards, so that they have a tendency to spring
downwards, by which means this part of the wing, which I term the palm,
strikes downwards along with the oars, being liberated and permitted to strike
at the same time as the oars; and this arrangement also contributes at all
times to enable this part better to resist the pressure of the air underneath,
which would otherwise have a tendency to bend the light extremities upwards.
These cords pass over small pulleys, or over one wheel and under another, which
is the most suitable arrangement. The position of these pulleys is indicated by

page_text: the letter k, Fig. 4; and they are conducted from thence to the arm of a crank,
which is shewn in Fig. 10, and indicated by the letter l, and by this means
they are drawn upwards along with the oars, and permitted to spring downwards
when they are required to: perform the stroke. The tensions of the different
cords which are attached to. this' part. are so arranged that no strain is caused
on the extreme points, and the practical effect is altogether different from that
which would be produced by the action of the compressed air underneath if
this disposition was not adopted:
ד'
th.
+
Figure 4 is a transverse section of the wing. Small notches may be cut in the
blades of the oars; or of a certain number of them, and valves' placed underneath
in such a manner as to permit the air. to pass. downwards, but not upwards. I
believe that the small notches or sinuosities observed in. some of the principal
feathers of most birds possessing the greatest powers of flight have this effect to
a certain extent. In the form of wing in which the oars are not required to
be closed I prefer setting them at a certain distance, one above the other, and
placing valves or flaps between them. in' such a manner that the air can pass
downwards, but not upwards, and this may even be effected in the more
complicated form represented in Figure 2, by the arrangement of the springs
ff, in a manner conformable to this object. In the more simple form the
oars are kept separate by means of steel stays. I place valves under the shafts
which are behind the oars, or a certain number of them, which also permit the
air to pass downwards, but not-upwards; the hinges of. the valves being attached
to the shafts; the distance between the shafts: at their terminations is greater in
proportion as they are placed farther from the fore.part of the wing. I consider
it advisable to form the hinder. part of the wing larger in proportion to the fore
part than is usual in.the wings of birds; the reason is, that any length of shaft
which is manageable in one part may be made manageable also in another,
whereas in the bird nearly the entire force seems to: exist in the fore: part of
the wing, the feathers in. that part being under the immediate.control of the
principal muscles and sinews.. The framework of the, wings, and also that of
the rudder or tail, is covered with a double covering of silk or other suitable
material, parchment or some stiff material being, introduced .between the two,
and the whole, is united by caoutchouc or copal varnish, or glue, or other
adhesive substance. Cross stays of steel passed. thro' small pieces of reed or
light o cane are placed. between the shafts to keep them expanded in all forms,
except that represented in Fig. 1. .The. wings.. are raised by means of cords
attached to the canes m, m, Figure 12;, these canes are sewed to the material
of which the wing cover. is formed,, which is silk or other similar material. The
wing covers, when an ærostat is used, are united at top to the ærostat, and may

page_text: be considered as prolongations of the ærostat. Fig. 12, in which one of these
is represented, is a longitudinal section of the ærostat with the entire apparatus
combined, the whole being supposed to be cut precisely through the middle
from stem to stern; one wing cover and one arrow head are consequently seen
in perspective. In the apparatus intended to be used without an ærostat, the
wing cover terminates in a point at top, which is inclined backwards. In the
small apparatus which is intended to be closed when not in use, the canes
which are attached to the wing covers are formed with joints, so that these
parts can be closed along with the other parts of the wings. The cords which
are used to raise the wings may be attached to the canes of the wing covers
either directly or by means of systems of pulleys; the former is very suitable for
a small apparatus, but I prefer the latter for large vessels. The canes of the
wing covers, or at least those to which the cords that serve to raise the wings are
attached, should be stayed to the shafts below. I prefer forming the wing cover
in the manner shewn in the transverse section, Fig. 4, and also in the section
Figuro 16, disunited at the extremity from the lower part of the wing in order
to permit free action to the oars & the extremities of the shafts, and the stays
from the canes of the wing covers should be so arranged as not to interfere
with this freedom of action. These stays may very suitably be formed of
elastic caoutchouc; the pulleys are of light wood, and the blocks are of
cork; the latter have small apertures only at the sides sufficient to allow the
necessary play to the cords, but no more. The tail is raised in a manner nearly
similar; the tail cover is formed of materials similar to the wing covers.
Figure 12 shows a longitudinal section of the two rudders or tails already
mentioned; pieces of flat elastic wood are used as cross stays for the wing and
tail covers. The cords which are used to raise the tails are attached to the
cancs n, n, Fig. 12; those which serve to raise the lower one may be passed
through the upper, or both may be raised together, but I prefer arranging the
cords in such a manner that each can be moved separately; they may be
furnished with valves, but these are not necessary. o, o, Figure 11, are similar
to the oars, and are fixed under the lateral shafts of the tail or rudder; these
shafts are similar to those of the wings, but lighter; the lateral shafts are
stronger than the middle shafts. The cords which are used to elevate or
depress either side of the tail or rudder are attached to the lateral shafts. These
shafts are stayed to the seat or hull, the stays being of elastic caoutchouc
or other elastic material, so that they can be drawn in any direction as far as
required and spring back when liberated, causing the tail or rudder to recover
its original horizontal position. The part of the tail indicated by the letter p,
is concave; but it is most so in the middle; the part q, is flat or nearly.so. This

page_text: form is given to the tail in a manner similar to that in which the same is
effected in the wings. The extremity of the tail may be made to strike the air by.
an independent action in a manner similar to the extremities of the wings; the
form of the tail may be varied as in different species of birds, a forked, round,
or cuneated form being given to it by making either the lateral or the middle
shafts longer or shorter, in proportion to each other. The alæ spuriæ are
represented in Figures 1, 2, and 11, in all of which they are indicated by the
letter r. They are formed of thin flat pieces of elastic wood, strengthened by.
pieces of elastic steel, the bases being attached to the fore parts of the wings
by cords similar to those used to attach the stems of the wings and the bases'
of the lateral shafts of the tail, except that they are much smaller and lighter.
They are set in such a manner that the alæ spuriæ spring strongly downwards
when not drawn in the opposite direction; they may also be pressed downwards.
by steel springs, but these latter are not absolutely necessary. The frames of
the hinder parts of the alæ spuriæ are formed of light steel rods, and the
covering is similar to the covering of the wings; they are formed with valves
which permit the air to pass downwards, but not upwards. The alæ spuriæ are
worked during the rising of the wings, and should perform several strokes
during that time, and they should also strike simultaneously with the strokes
of the wings. Small tubes partially filled with shot or other material which
will slip easily from one end to the other are placed along the fore parts of the
wings, in such a manner that the shot or other material within the tubes shall
fall to the farthest extremity of the tube as the wing strikes downwards, and
fall back when the wing is raised, and by this means increase the force of the
stroke at the moment it is most required in consequence of the compression of
the air underneath caused by the action of the wings. 8, Fig. 2, is a stay
which is of steel and flat, and having a sharp edge in front; it is of a similar
form in all modifications of. wings; it is attached to the fore part of the seat or
hull by a spring which permits freedom of action to the wing; it represents
the membrane which is placed in a similar position in birds, and is formed like
it, concave in front, as I consider that this formi permits the air to pass more
freely under that part of the wing where the force of the current acts with the
greatest advantage; other stays united to the seat or hull in a similar manner
are placed behind this. When the apparatus is intended to be used by a single
person the seat is formed as nearly as possible like a small saddle, on which the
person sits as on horseback, the saddle being made as narrow as possible so as
to permit him to walk before rising and after descending, the machinery used
for working the wings being placed in front, or the wings may even be worked
by cords merely pulled. 'by the hands... Rests for the feet while flying are so

page_text: arranged that they can be raised, so as not to inconvenience the person while
walking.
Figure 1 represents the form of wing best adapted to this purpose. When
closed the joints t, t, reach to about the 'ancles; the parts u, u, close backwards,
and the extremities of the oars forwards: The tail may be made to close
downwards, and when in that position its extremity should reach to about the
same distance from the ground as the joints 't, t; w, w, are openings which
admit the thighs of the person who occupies the seat or saddle."
Figure 5 represents a part of the apparatus which I term the scapular sail;
its office is similar to that of the upper rudder or tail in large vessels; it affords
great assistance in steering and also in sustaining the weight. The canes x; ;
pass under the shoulders, and the lower ends are attached by cords to the front
of the saddle in such a manner that the scapular sail may be set at any angle
required, and these canes may be disunited from the saddle when the apparatus'
is no longer required for use, and the scapular sail may then be closed down-
wards behind the person's back; and the canes may be formed with joints so as
to admit of the ends being closed downwards on the breast, or they may be
formed so that they can be'disunited about the centre. The part p is convex
above and concave below, and the part q is flat or nearly so. Light cross stays.
should be used, and it should be supported by stays from the waist. or from the
back part of the saddle, the upper ends being jointed to the ribs or shafts, and
the lower ends attached by cords or other convenient means admitting of their
being freed when it is desired to close the apparatus; these cords should be
attached to springs fixed to the saddle.. The framework is covered in a manner
similar to that of the tail or rudder, except that the materials may be lighter;
it may be furnished with valves, but they are not necessary..
Figure 6 represents a small parachute, the ribs of which are jointed to a
collar which is clasped round the neck: y, y, are two ribs or pieces of cane or
whalebone which are united as one when in use, but may be disunited in order
to admit of the parachute being placed in its position or removed at pleasure:
It is kept expanded by stays, the lower ends of which are attached by cords
or other.convenient means to a belt which is, fastened round the waist in such
a manner that they can be disunited when desired, and the parachute can then
be partially closed over the shoulders.
!:
Figure 7 represents a parachute in the more strict meaning of the word. It
is only intended to be used with an apparatus suitable for a single person and
may be made so small as to admit of being carried in the hand when not in
use. The circular part is formed in a manner nearly. similar to an umbrella,
except that I prefer using the light. canes or reeds that I have mentioned to

page_text: .
form the ribs, the strong ends being placed in the centre and the small points
outwards; and I prefer making the stays or stretchers rather longer in
proportion than in an ordinary umbrella for the sake of greater strength, and
also to increase the size of a vacuum chamber which I place in this part, the
principle of which is explained' under the third claim. These stays or stretchers
are of steel; they are arranged as nearly as possible like those of an ordinary
umbrella so as to admit of the parachute being closed or as nearly so as
possible, when not in use. I term the parts, z; the wings of the parachute';
for the sake of distinction I term the wings which are attached to the seat or
saddle the wings proper, and I apply the same term to the wings attached to
the hull in large vessels. The wings of the parachute are formed of canes or
reeds rather stronger than those used for the circular part, especially the
foremost canes of each wing, and very thin boards may be added to increase
the stiffness of this part, but they are not necessary: The canes or reeds 'which
form the framework of the wings of the parachute are jointed to the lower
part of the sliding tube to which the stretchers are jointed 'which support the
circular part. c, c, are two canes or pieces of light wood united at top where a
cylindrical sheath or tube receives the lower end of the central shaft of 'the
parachute, in which it is moved upwards and downwards, carrying with it 'thé
winged parachute; & this movement assists by the compression of the air within
the concave part to raise and support the weight of the person and apparatus.
Motion may be communicated to the parachute in any convenient way, but I
prefer jointing the ends of canes or reeds such as I have described to the canes
which serve as ribs to the wings of the parachute, the opposite ends being
attached by cords or other convenient means to the canes which are placed
over the wing canes (that is! to say, the covers of the wings proper) in such a
manner that they can be removed when the apparatus is required to be closed,
but when fixed in their place they cause the parachute to be moved upwards
and downwards by the movement of the wings proper: I prefer attaching the
lower ends of these canes or reeds to springs similar to that represented in Fig. 3,
but without the additional spring: d, and extremely light and small. These
springs should be attached to. the canes of the covers of the wings proper, and
the ends of the canes which communicate motion to the wings of the parachute
should be attached above themi: The apparatus may be so arranged that the
movement may be alternate, the parachute rising as the wings proper descend,
but I prefer. the arrangement I have described... It is advisable to use light cross
stays similar to those used for the wings proper and tail in the fore parts of the
wings of the parachute, but they are-not necessary in the hinder parts: The
wings of the parachute are furnished with valves similar to those of the wings

page_text: proper, the joints of which are attached to the canes which form the ribs or
shafts of the wings. When the parachute is closed, the wings may be made to
close upwards for greater convenience. Cords are attached to the lower end of
the central shafts, the opposite ends of which are attached to springs which are
set under the seat or saddle; these springs are drawn upwards as the parachute
is raised, and by their reaction cause it to descend with a quick motion, &
prevent the force of the strokes of the wings being materially lessened by the
latter having to draw down the parachute; elastic caoutchouc is the most
suitable material for these cords. The tube is jointed to the canes c, c, in such a
manner as to admit of the parachute assuming an inclination conformable to
that of the wings proper, and cords are attached to the wings and also to the
fore and hinder parts of the parachute, the opposite ends of which are attached
to the seat or saddle in such a manner that the inclination of the parachute
can be regulated at all times with precision, and the arrangement is such that
it can not only be inclined. laterally, but also raised or depressed in front or
behind as far as this is requisite. All the cords in every part of the apparatus,
whether it be of a small or large size, or used with an aerostat or otherwise,
the tension of which requires to be altered under different circumstances or
regulated with precision, are either attached to keys resembling those of a
musical instrument, but having screws cut on them and furnished with pins or
with ratchet wheels and detents, to prevent them from turning except when
moved by the hand, or pullies are used, which are furnished with small ratchet
wheels fixed on the axles outside the blocks where detents are so placed as to
engage in the teeth. It is most advisable both in the small apparatus and in
large vessels that each set of cords should be of a distinct color, and that the
part which is either moved or stayed by these cords should be of a cor-
responding color, as by this means confusion is avoided. An air cushion may
be placed on the canes or pieces c, c, against which the person using the
apparatus can rest his head and shoulders, the arrangement being such that it
can be removed at pleasure. The ends of the canes or pieces c, c, are attached
to the saddle by cords or other means admitting of their being removed when
desired. The wings of the parachute are covered with a material similar to
that used for the wings proper, except that it may be lighter, and that used for
the upper part of the parachute may be lighter than that used for the wings.
The principle and construction of the vacuum and medium chambers is
explained under the third claim. The upper part of the parachute is filled with
atmospheric air, which may be removed as from an air cushion when the
apparatus is not required for use. In the small apparatus intended for the
use of a single person, the wings proper are worked by winches, a separate

page_text: winch and handle being appropriated to each wing; one of these is turned by
the right hand and the other by the left, and the cords which are used to raise
the wings are wound round the axles which are turned by the winches; one of
these is represented in Fig. 8, indicated by the letter a. This axle carries a
wheel having angular teeth which communicates motion by gearing with the
teeth of another wheel, having angular teeth also, which is fixed on the axle b.
The teeth are so inclined that they engage while the wing is rising, but slip
while it is performing the stroke; and in order to effect this more perfectly I
prefer attaching the teeth by joints in such a manner that the joints shall yield
when pressed in the opposite direction from that in which they are required to
act. A spring may also be so placed that it shall draw the axle b towards the
axle a while the wing is rising, the arrangement being such that it may slip
in a slight degree from it as the wing strikes downwards. The axle 6 has a
crank attached to it, at the extremity of the arm of which is a pin which turns
freely in a socket, and to this the cords which serve to work the alæ spuriæ.
are attached, the proportion of the diameters of the wheels, or of the wheel
and pinion, by which motion is communicated from the axle a to the axle b
being such that the alæ spuriæ shall perform several strokes during the
rising of the wing, and also strike simultaneously with it. The most convenient
way of working the oars in a small apparatus of this kind is to attach the ends
of the cords used for that purpose to a pin turning freely in a socket at the
outer end of the handle c, or fixed at the extremity of the arm of a crank
which is set on the end of the handle, as represented in the Figure. I prefer
the latter arrangement, as by this means the arm of the crank can be formed
with a joint in such a manner that it will yield as the oars strike downwards,
but be inflexible when the strain of the cords acts in the opposite direction,-
while the arm of the crank is describing the opposite half circle; and I prefer
forming the arm of the crank which communicates motion to the alæ spuriæ in
a similar manner; the object of this is that the stroke shall be instantaneous;
this peculiar arrangement is, however, not absolutely necessary. When the
wings are of a large size and used with an aerostat, and a separate person can
be employed to work each wing, wheels are used for the purpose as represented
in Figures 9 and 10, the first being a side view and the second an end view.
The persons who turn the wheels are placed nearly in the positions of men
rowing, but rather more horizontal. Figure 9 represents a man turning a
wheel a, with a smaller wheel b in combination with it; the part c is formed
by two boards with an air cushion between them; his head also rests on an air
cushion; a strap is placed across his breast, which, combined with the other
arrangements, prevents him from being drawn forwards or raised from his
B

page_text: position by the action of the wheel, which might otherwise have a tendency to
draw him in that direction. The periphery of the wheel a is furnished with
boards set at a suitable angle for the feet of the man turning the wheel to
press against them; the smaller wheel b communicating with the larger one by
means of an endless band, is turned by the hands of the same person, so that
both hands and feet are employed simultaneously in the movement. I under-
stand that a position in some respects similar to this has been suggested as an
advantageous one for making use of a man's strength, but I am not aware that
it has ever been applied, at least to äerial navigation; for which I consider it par-
ticularly suitable. I do not claim the idea, but I consider it peculiarly adapted
to this purpose. The cords which serve to raise the wings are wound round the
wheels d, d; a separate wheel and axle with its corresponding hand wheel is
always appropriated to each wing; the wheels are let go the moment the wing
is raised to the required elevation, and the springs. cause it to perform the
stroke by their re-action. E is a board under which is a spring so arranged
that it yields to a sudden pressure, and the person working is enabled to slip
his feet in an instant from the wheel by pressing this downwards. To this board
are, attached cords, the opposite ends of which are fastened to detents which
engage in the teeth of ratchet wheels, which are so placed as to prevent the
recoil taking place before the proper moment; but these cords are attached to
the detents in such a manner that when the board E is pushed down; the
points of the detents are raised and liberate the axle. I prefer making use of
two endless bands passing over the wheels fif, one of these wheels being
placed at each side of the wheel a, as represented in Figure 10, and I make
use of two wheels on which to wind the cords that serve to raise each wing;
these last mentioned wheels are indicated in the Figure by the letters d, d.
Any number of persons that the vessel is capable of accommodating may be
employed to work the wings on this principle, the axle may be lengthened and
an additional number of wheels may be fixed on it; but I prefer placing men
in positions suitable.to. the form and size of the vessel, each working a separate
wheel with its corresponding hand wheel, and attaching separate systems
pulleys to an additional number of canes:
1, Figure 10, is the arm of a crank to which the cords which serve to raise
the oars are attached, as already mentioned, these cords being first collected
in a small sheath which is formed of a small piece of reed or other light
material, and passed through guide pulleys in suitable positions. The crank is
fixed on an axle, to which motion is communicated by means of a wheel fixed
on the axle. the relative diameters of these being. such that the oars shall
strike downwards either once, twice, or a greater number of times during the.

page_text: rising of the wing, but they must always strike downwards, simultaneously with
the stroke of the wing. h is the arm of a crank, to which the cords, which
serve to raise the alæ spuriæ are attached in a similar manner to that in which
those from the oars are attached to the arm of the crank l. This crank is fixed
on an axle to which, motion is communicated by a wheel fixed on the axle 9,
but the diameters of these bear such a proportion to each other, that the alæ
spuriæ perform several strokes during the rising of the wing. The arms of-the
cranks may be formed in a manner similar to those used for the small appa-
ratus already described, and I prefer forming them in that manner. The
reason of giving a curved form to the cranks as represented in the Figure, is
more effectually to prevent any risk of the cords tangling, or catching, but this
form is not absolutely necessary. I prefer causing the cords which. serve to
work the wings, and also those which serve to work the oars and the alæ
spuriæ, to pass through guide pulleys placed as low down as they can be con-
veniently, and from thence to the axles or cranks. The arrangement repre-
sented in Figures 9 and 10, and also that represented in Figure 8, is adapted.
to the right wing only, but that used to. work the left is exactly similar, except
that the handle in Figure 8 and the 'cranks in both, arrangements are set at
the opposite ends of the axles for the left wing. Anti-friction rollers and all
known means of diminishing friction which can suitably be introduced should
be used to remove all obstruction, as far as possible, from the axles on which.
the wheels are fixed, round which the cords that 'serve to raise the wings are
wound, as these cords must unwind themselves, and while so doing, turn the
axles in the opposite direction. When the wings are striking downwards, the
most simple means' is, to place one or more cylinders which are permitted to
turn freely round each axle, and I make use of these even for the axles of the
pulleys. With regard to the axles which carry the wheels on which the cords:
that serve to raise the wings are wound, I consider it most suitable to place
anti-friction rollers all round the axle, each of these turning freely. on a
separate axle, the ends of which are fixed in the sides of the box; or they may
even turn in bearings and the hollow cylinder; or even more than one may be
used in addition. The ratchet wheels being fixed on the inner axles which carry
the wheels round which the cords are coiled, do not interfere with this arrange-
ment, as the detents engage only while the wings are rising, and it is only
during the stroke that it is requisite that all friction should be avoided as much
as possible; washers or small discs turning freely round the axles so as to
diminish the friction against the sides of the frame should also be used both
for these axles and also for those of the pulleys. The wings may be made to
perform half or quarter strokes when this is desirable, by liberating the wheels
.
□ 9

page_text: when the wings have been raised to the elevation desired. This can be done
either with one wing or both, by the person or persons who work them
slipping their feet from the boards placed round the large wheels, at the same
time pressing down the boards, one of which is shewn in Figure 9 and
indicated by the letter E. The cords which are attached to these boards having
their opposite ends attached to the detents as already mentioned, which are
disengaged from the teeth of the ratchet wheels by pressing down the boards,
the wheel 6 must be let go at the same time. It is, however, necessary that this
should be so calculated and arranged that the half and quarter strokes should
correspond with those of the oars and alæ spuriæ, so that they may strike with
the stroke of the wing. The wings or either of them may be worked more
slowly or otherwise by altering the speed with which the wheels are turned..
An additional person should be employed to attend to the rudder, or this office
should be performed by the person who commands the others. But the steering
is effected principally, at least under difficult circumstances and in strong gales
or contrary winds, by means of the wings; and for this reason, among others,
I consider men's force much more suitable than any other power to work the.
wings, as judgment is required, more or less, in almost every stroke, and it is
scarcely ever suitable to work both wings exactly alike.
a, Figure 12, is a small propeller intended to be used in a manner somewhat
similar to the oar of a gondola, but more for the purpose of propulsion than
steering, though it assists also in steering; it is formed by two thin pieces of
elastic wood, each of which is strengthened by a thin flat piece of elastic steel,
their bases being moveable on pins fixed at each side of the hull, in such a
manner that the extremities which pass beyond the stern and form the propeller
can be either elevated or depressed at pleasure. The propeller is set at any
angle required by means of adjusting screws, or any convenient arrangement,
and is made to act on the air by drawing it alternately to one side and the
other, or, if desired, to one side only, its elasticity admitting of this and causing
it to spring back when liberated; it is sometimes most suitable to draw it to one
side only. The form of wings used for aerostats which are intended specially for
perpendicular ascent are represented in Figures 15 and 16; the first shews the
under surface as it would be seen from below if ascending with the aerostat
combined, but the wings only of the aerostat can be seen when viewed in this
position; the second, which is a vertical section of same, shews the manner in
which the winged car or hull is used in combination with the aerostat. E, E,
are the wings of the aerostat, and e, e, are the wings proper. The wings proper
may be attached in such a manner as to admit of their being either set or
worked at any angle required, or even reversed and made to act upwards in!
.

page_text: order to facilitate the descent. X, X, are small propellers similar to that
represented in Figure 12 and indicated by the same letter; but in this instance,
they are so arranged that they can be set or worked horizontally or made to
strike upwards if required; when descending they can be set or worked at any
angle required. The different modifications represented in the Drawings are
those which I consider best adapted to the particular purpose for which each
is specially designed; but I do not limit myself to these exact proportions as
the principles admit of almost infinite modifications in the minor details.
Secondly, my improvements have reference to the form of the envelope
containing gas or air, which I term the aerostat. Figure 11 represents the
lower surface of an aerostat of the form that I consider best adapted to loco-
motion or transit from place to place, but I do not limit myself to any
precise proportions; it is represented in combination with the hull, the wings,
and rudder or tail, and other parts complete as it would be seen from below
if sailing or flying over head. Figure 12 is a longitudinal and vertical section
or elevation of same, and Figure 13 shews the upper part of same. Figure 14
is another modification, more particularly formed for speed; the same letters
indicate similar parts in all these figures. A is the aerostat proper; B is the
vacuum chamber; and C is the medium chamber. The principles of these and
their construction are explained under the third claim. D is the outer.com-
partment, and E, E, are the wings of the aerostat.
The aerostat proper in
vessels of this class may be filled either with gas or with rarefied air. The
situation of the stove is shewn in Figures 11 and 12, and on a larger scale in
Figure 17, in all of which it is indicated by the letter S; the particulars as
regards its form and arrangement are described under the 4th claim. The
outer compartment of the aerostat D is filled either with nitrogen gas or atmo-
spheric air. 9, 9, are the two leading points which are formed in this manner,
in order to present the least resisting surface possible to the air. Over the
parts h, h, which are of glass strengthened and sustained by light bars of steel, are
lamps so disposed as to throw the light downwards, in order to show, as far-as
possible, the land or water over which the vessel is sailing or flying during the
night. i, i, Figures 11 and 12 are steel tubes covered with canes, or reeds, or
bamboos, to strengthen them. It is most advisable to place a bamboo under-
neath, and the lighter canes or reeds above these tubes serve as chimneys
through which the smoke or heated air passes from the stove; the tops of these
chimneys, which are seen in Figures 13 and 14, and one of which is seen in
perspective in Figure 12, in all of which they are indicated by the letter K,
are furnished with a plate of perforated metal or wire gauze. 1, 1, in the same
Figures are the tops of the chimneys through which the smoke or heated air

page_text: passes from the lamps; both chimneys are pointed at the top, and the trans-
verse section of the latter is oval, with the sharp edge in front. 'I consider
that the smoke or heated air issuing from these chimneys will conduce to a
certain extent to relieve the fore part of the aerostat from the atmospheric
pressure, a very small current of heated air being found to have a certain effect
in that respect, and these chimneys are so placed that the smoke or heated air
issuing from them, after ascending, is driven backwards towards' that part of
the aerostat which most requires to be relieved from the pressure. When
rärefiěd air is used; the heated air from the stove must be made to pass into
the fore part of aerostat proper, but I consider the arrangement shewn in the
Drawings to be the most perfect.
The parts 9, g, which I term the arrow heads, are formed of steel frames
sufficiently strong in the centre but gradually lighter towards the front and
sides, and covered with thin steel plates which project beyond the frames in
front, and on the inner sides the latter is slightly concave, as I consider that
this form tends to divert the current of air from the part of the aerostat imme-
diately behind it and to direct it towards the main air channel H. These
arrow heads may be so constructed that they can be turned towards either
side, in order to facilitate the steering of the vessel, and when so constructed,
wire
a or wire cord should be attached to each side of each arrow head, the
opposite end of which should be conducted to the lull; but this is not
necessary. Any material used for combustion in the lamps can be drawn up by
cords and pulleys along the outside of the tubes i, i. "It is most suitable that
the lower surfaces of the wings proper and also of the acrostat should be of as
light a color as possible, and metallic leaf, such as is sometimes used for small
rarified air balloons, may very suitably be employed for those parts whose
situation is best adapted to reflect the light in any degree from the lights in
the arrow heads or frame lamps placed in any convenient positions in the hull
of the vessel. The bottom of the hull and also of the pilot bont which is
described under the fourth claim, may very suitably be covered with very thin
plates of metal, which will in some degree act as reflectors to lights when let
down from the hull or from the pilot boat when descending.
+
It is advisable to cover the fore part of the outer envelope of the aerostat indi-
cated by the letter m, Figures 13 and 14, with very thin plates of steel which are
attached to long canes or bamboos, or to bamboos lengthened by the addition
of a number of canes or reeds, cach lighter than the preceding, so as to pre-
serve a gradually diminishing form fromthe base tothe top, light steel rods being
passed through them; these canes or combinations of canes are represented
in Figures 13 and 14, indicated by the letter n. 0, 0, are two similar canes

page_text: or combinations of canes. They are used in all parts of the aerostat which
require to be kept stiff or of a sharp or angular form; they are sewed to the
material of which the envelope is formed, which is cut to the required shape.
p is a long cane or combination of canes which serves to give as sharp a form
as is consistent with the general formation to the upper, part, of the aerostat.
The foremost parts of the prolongations of the outer envelope in front may be
filled, with bladders inflated with atmospheric air, or nitrogen gas, which will
contribute to render this part stiff, without adding materially, to the weight.
The length of the chimneys contributes to diminish the risk of, fire, more
especially as the smoke or heated air is thereby conducted to the fore part of
the aerostat, which is inflated with nitrogen gas or atmospheric air. But I
consider it advisable to place plates, of perforated metal or wire gauze in one
or more parts inside these chimneys in addition to those which I have men-
tioned as, placed at the tops; and I consider it advisable to cover, the tubes or
parts of them with asbestos cloth, but this is not absolutely necessary.......
H, Figures 11 and 12, is the main air channel, through which, the air passes,
without obstruction; from stem to stern. Between the aerostat and the hull,
smaller air channels are also placed in other parts, to lessen; the atmospheric
resistance, which discharge, the air under the wings of the aerostat where. it
acts most advantageously. The entrances or mouths of two. of these air
channels are covered in front by projections, indicated by the letter f In
Figures, 13 and 14 these projections are continued to the front peak or pro-
longation. F. The wings of the aerostat E, E, may be considered as prolonga-
tions of the outer envelope, except inasmuch as they are divided by the air
channels n, n; they are brought to. as sharp,an edge as their general form will
admit: At the sides where the canes t, t, are sewed to the silk or other
material of which the envelope is formed, cords are attached to these canes,
the opposite ends of, which are attached, to the wings proper in such a manner
that the wings of the aerostat rise and fall with the wings proper, that is to
say, they are forced downwards by the strokes of the wings proper, and I con-
sider that the spring of the air after the stroke, joined to the force of the
currents passing through the air channels and by the side of the aerostat, will
suffice to raise them as far as required. I consider atmospheric air generally
to be the most suitable for inflating the wings of the aerostat, but gas may be
used, to give them greater, buoyancy if desired. The cords that are used to
conimunicate. motion to the wings: of: the aerostat should, be, made, to, pass
through guide pulleys in suitable positions, so as to give an advantageous
direction to the strokes of the wings of the acrostat, and passed from thence to
the wings proper The wings of the aerostat assist most materially in steering

page_text: the vessel, besides the advantage of counteracting any tendency that the action
of the wings proper alone might have to carry forward the hull of the vessel
in advance of the aerostat above the channels n, n. Figures 11, 13, and 14
permit the air to pass downwards from that part of the upper surface of the
aërostat which would assume a form, to a certain degree, hollow or concave,
when the wing is at its full elevation; and these air channels discharge the air
which passes through them under the wings, as well as the air channels
already mentioned. All the air channels, except the main channel marked H,
are formed in a manner, to a certain extent, similar to wind sails; but I prefer
bending the pieces of light elastic wood, which serve to keep them in their
form in an oval shape, the joining of the ends forming the narrow part, which
is placed below for the air channels which pass under the projections f, f; and
I make use of two pieces of thin flat wood for a similar purpose, to give the
required form to the air channels n, n, which are pointed at both sides. When
the two pieces are united, the air channels n, n, are furnished with valves, which
permit the air to pass downwards, but not upwards. As regards the main
channel which is open below, except so far as the hull occupies the lower part,
I keep it in the required form, which is concave, by means of thin flat pieces of
elastic wood similar to those used for the smaller air channels, but broader
and rather stronger; they are bent like bows by their strings and sewed into
the material, the strings being uncovered. These bow strings, as they may be
termed, may very suitably be made of elastic caoutchouc. The ends of the
bows or flat pieces of wood are made fast to the canes or bamboos w, w, which
serve to strengthen the sides of the main air channel, and to keep this part in
the required form. The strings nevertheless render the whole much stronger
and more perfect. The positions of these bows are indicated by the lines x, x,
Figures 11 and 12. Y, Y, Figure 11 and Fig. 12, are what I term the stern
fans; these are attached to the bamboos or canes which serve to keep the
hinder part or stern of the aërostat in the required shape. These fans direct
the air against the stern of the aërostat, and also contribute very materially.
towards the propulsion of the vessel by the direction of the stroke backwards.
They are also extremely useful in steering, as either may be used independently
of the other, and they may even be so arranged as to strike forwards instead
of backwards when required to check the speed of the vessel, or one may
be made to strike backwards and the other forwards when turning or altering
the direction of the vessel. They are attached to the canes or bamboos
z; z, by means of flat pieces of elastic steel, which may be said to act at the
same time as joints and springs; these yield when the fan is pulled to either
side, and spring back by their elasticity; at least so far as their strength will

page_text: permit. They are worked by cords attached to the fans, which pass to the hull
of the vessel. It is advisable to have cords attached at both sides of each fan,
both to assist the stroke, as their situation does not admit of very strong springs
being used, and also to give the power of causing them to strike forwards as
well as backwards when so required; this is very useful before descending to
check the speed of the vessel. The wheels and axles that are used for
working the wings may be made to communicate motion to these fans by the
use of ordinary combinations, but it is much more advisable, when the vessel is
sufficiently large to admit of it, to work them separately from the wings.
And the same axle or axles which give motion to these fans, may also com-
municate motion to the small propeller x, Figure 12, the principle of both
being to a certain extent similar. As regards the materials of the envelopes
which form the aërostat proper and the outer covering, they may be formed in
the usual way and of the ordinary materials; but I consider it most advisable
to have cords sewed in all the seams, and the ends of these cords made fast to
the hull, the cords being prolonged sufficiently for that purpose. Canes or
bamboos are used to give stiffness to any part requiring it, in the manner I
have already described; but I consider the most perfect manner of forming
the envelopes, especially very large aërostats, is to place parchment or very
light steel plates between two pieces of silk or other suitable material, and to
unite them by means of caoutchouc in a manner similar to that in which two
pieces of cloth are united in forming air-proof fabrics. These pieces of parch-
ment or steel plates should be placed between the scams, so that the parts
immediately forming the seams permit a certain degree of expansion to the
entire; when steel plates are used, the edges should be covered with a little
cotton or other soft substance to prevent them from injuring the material, and
there should also be an additional thickness of caoutchouc round the edges.
In very large vessels, two pieces of material formed in this manner may be
united, the seams of the one piece being placed in the intermediate part between
the seams of the other piece, in order to render it still more impervious to the
gas, and to make the strength more equal throughout.
When the vessel is sufficiently large, it is very advisable to make use of two
or more separate envelopes in addition to those represented in the Figures,
each envelope containing a denser medium or heavier description of gas or
air or less rarefied than that contained in the compartment below it. The
principle of this arrangement is more fully explained in the third claim. An
outer envelope with prolongations in the form of wings and also prolonged in
the form of two points in front, as I have described, or as nearly so as the form
will admit, may be added to any ordinary balloon; and a winged boat may be

page_text: used in combination with it, but it will necessarily be much less perfect than
the more complete arrangement that I have described.
When the aerostat is intended specially for. perpendicular ascent, and not
for transit from place to place, I form it as. represented in Figures 15 and 16.
Figure 15 is a view of the lower part as it would be seen from below when
raised in the air; Figure 16 is a vertical section of same. The same letters
indicate parts similar to those indicated by these letters in the preceding Figures.
A is the aerostat proper, which is filled with hydrogen gas or gas of the ordinary
description, but I prefer pure hydrogen; B is the vacuum chamber, and
C, the medium chamber; and D is the outer envelope, which is filled either
with ordinary. gas of a greater specific gravity than that in the aërostat
proper, or with nitrogen or atmospheric air, or combinations of these, according
to the height to which it is required to, ascend. E, E, are the wings of
the aerostat, eight in number, from which cords pass to the wings proper
e, e, so that they strike downwards along, with the wings proper. I do not
limit myself to this exact number, as either a greater or a smaller number
may be used, but I prefer this number generally, especially for aerostats of
a large size; four is, however, a very suitable number for small aerostats.
n, n, are air channels, the object of which is similar to that of the air
channels indicated by the same letters in Figures 11, 13, and 14, but each
is adapted to the particular form and design of the aerostat with which it
is used. These air channels are furnished with valves, which permit the air to
pass downwards, but not upwards, except when opened by pulling a cord,
which may be done when desired. All the valves may be made to open in a
manner similar to the valve of an ordinary balloon by having cords attached to
them, the opposite ends of which are attached to the hull in such a manner
that the valves can be opened when it is desired to cause the vessel to descend.
Although the aerial vessel represented in Figures 15 and 16, is specially
designed for perpendicular ascent, it can nevertheless be guided, to a certain
extent, by working the wings on one side only and setting the others at any
angle required. The outer envelope is represented in the Figure slightly
pointed at the top, and although this is not necessary, I prefer forming it in
this manner in order to throw off rain in wet weather, and also from the
belief that it will, to a certain extent, suffer less resistance from the atmo-
spheric pressure when ascending. A pointed form is much more suitable than
any other for the vacuum and medium chambers, a section of which is repre-
sented in Figure 16. The principle and construction of these are explained
under the third claim, and it is most convenient and suitable that the aerostat
proper, and also the outer envelope should be of a similar form: An envelope

page_text: with prolongations in the form of wings, as here described, may easily be
placed over an ordinary balloon, and the winged car or hull may be adapted to
it, but it will be much less perfect than the more complete combination
described. Gold-beaters skin may very suitably be substituted for parchme
or steel plates in vessels of this description in forming all parts of the enve-
lopes which are not exposed to a very strong pressure.
"
Thirdly, my improvenients have reference to the formation of vacuum
chambers or parts of the aerostats, and also of the wings and parachute and
other parts of the apparatus from which the air is either partially excluded or
exhausted to the extent generally understood when the term vacuum is used,
or nearly so, according to circumstances. The large vacuum chamber B,
Figures 12 and 16, has not only the advantage of serving as a vacuum for the
purpose of rendering the atmospheric pressure more efficacious in elevating
and propelling the vessel, but serves also to admit the gas from the aerostat
proper when too much expanded by heat or great elevation, and by this means
the loss of gas is prevented, as it can be again returned to the aerostat proper
when desirable; and this chamber or compartment also serves when not
occupied by the gas to admit the atmospheric air when it is desired to descend.
These two uses do not interfere with each other, as they are required at
different times. In the interior of the vacuum chamber is a bag or envelope
of silk or other suitable material which is drawn by cords towards the aperture
a, when it is desired either to return the gas to the aerostat proper or to
expel the atmospheric air; in the former case the valve 6 is opened, in the
latter case the valve c² is opened. The gas is admitted when so required through
the valve either by the pressure of the gas, a spring being so arranged that
it shall yield when the pressure acts with a certain force, or it may be furnished
with a cord, by pulling which the valve is opened in a manner similar to that
of an ordinary balloon, or both the spring and cord may be used for greater
security. When it is desired to admit the atmospheric air the valve c² is opened.
A cord should be attached to the upper extremity of the bag to draw it upwards
when it is desired to admit either the gas or atmospheric air, and, this cord
should pass down at the stern of the aerostat to the hull. I form the lower
and hinder surfaces of the vacuum chamber of silk or other similar material
doubled with parchment or steel plates between, and united in the manner I
have already described; and I place inside this a close network which may be
of ordinary material, but I prefer elastic india-rubber cords; within the net-
work I place cords which should be drawn tightly to any convenient parts
which are strong enough to bear the strain. I prefer that these cords should
be of elastic caoutchouc. In the stern of the aerostat I draw these cords across,

page_text: attaching the extremities to the canes or bamboos, or combinations of canes z, 5.
Part of these canes or combinations of canes are seen in Figure 11, in which
the stern of the aerostat is seen in perspective, and in this view it is necessarily
fore-shortened; one of these canes or combinations of canes is seen more
perfectly in Figure 12. It is most suitable to attach one extremity of each cord
to the lighter part of one of these, and to attach the opposite end to the
stronger part of the opposite one, by this disposition the cords cross each other
obliquely. The light canes or combinations bear a strain by this arrangement,
which they would not otherwise have sufficient strength to sustain, and from
every point in which either extremity of any of these cords is attached to either,
a stay proceeds to the hull which sustains the cane by drawing it at the same
time in the opposite direction, or as nearly so as possible; these canes or com-
binations of both are lengthened in a manner similar to that already described.
By the arrangement I have described, the network sustains the envelope, and
the first mentioned cords sustain the network, when the pressure of the external
air compressed and agitated by the action of the fans y, y, as well as by the
force with which it rushes through the air channels as the vessel is urged
forwards, acts against the hinder surface of the vacuum chamber. Pieces of
elastic wood or bows nearly similar to those used for the main air channel may
also be used for this part of the vessel, with this difference that both the bows
and their strings should be placed within the envelope and behind the net-
work and sustaining cords, the bows or pieces of elastic wood being in this
case curved outwards. This arrangement will give a convex form to the stern,
and it is most suitable to draw the cords which are used to communicate motion
to the wings of the aerostat to guide pulleys fixed near the centres of these
bows in such a manner that the tension of these cords will contribute to draw
the centres of the bows outwards, and so assist in preventing them from being
forced inwards by the pressure of the air without; and this position is also
very suitable to give a suitable direction to the strokes of the wings of the
aërostat.. The lower surface which is subjected to a similar pressure is sustained
by the bows or pieces of elastic wood x, x, as the lower part of the vacuum
chamber is immediately over the main air channel, and extends over the greater
part of it; that part, however, which forms or corresponds with the lower
surface of the vacuum chamber, is sustained by a network and sustaining cords
inside similar to that already described. In aerostats of the form repre-
sented in Figures 15 and 16, the lower surface of the vacuum chamber is most
conveniently sustained by means of a number of concentric hoops sewed to the
material, these being sustained by a network and cords within, and cords should
also proceed from these hoops to the hull. All these cords may be of ordinary
.

page_text: material, but I prefer elastic caoutchouc. The upper part or roof of the
vacuum chamber is formed of a very light trellis work of slit canes or reeds,
to which bladders or small bags of silk or other light material, so prepared and
varnished as to be impervious to gas or air, are attached, one of these being
attached to the trellis work at each point where the canes or reeds cross each
other, and being of such a size and proportion that when inflated the sides of
all the bladders or small bags touch and slightly press against each other as is
seen in the longitudinal section of the aerial vessel, Figure 12, with this
chamber or compartment in its proper position indicated by the letter B, and
in Figure 16, where it is indicated by the same letter. A small quantity of
air or gas is introduced into these bladders or small bags so that they become
fully inflated when the greatest degree of exhaustion takes place in the vacuum-
chamber. Smaller bladders or bags are placed over these in order to render the
upper surface as nearly even as possible, these latter having also a small
quantity of air or gas within, so as to become inflated at the same time as the
first; any soft light substance such as down, is then placed above to fill the
remaining intervals, a material at the same time light, soft, and elastic, such as
eider down is the most suitable. This is covered by an envelope of silk or other
suitable material doubled with stiff paper or other light material between, and
united in a manner similar to that already described; but a much lighter
material is suitable for the covering of the upper part than for that against
which the currents of compressed air are made to act. The upper part of the
vacuum chamber in the form represented in Figure 12, is as sharp as is con--
sistent with the general principles and arrangement, that is to say, similar to the
front of a cuirass or what is commonly termed a pigeon breast, or it may be
rather sharper. A cane or combination of canes, such as have been already
described, is used to sustain the upper part in the form represented in Figure 16;
the vacuum chamber terminates at top in a point. The difference of weight
between so small a quantity of gas or air as is required to be introduced into
the bladders or small bags is so trifling that I prefer generally to make use of
atmospheric air for this purpose, especially in locomotive vessels. The roof of
the medium chamber C is formed in the same manner as the roof of the
vacuum chamber, but a larger quantity of air or gas must be introduced into
the bladders or bags as the gas or rarefied air in this chamber or compartment
is never exhausted to the same degree as in the vacuum chamber, this
chamber being intended to lessen the downward pressure of the gas or air in
the aërostat proper above.
In large vessels any number of medium chambers may be used that may be
found suitable; each containing a denser medium in proportion as it is higher

page_text: or further removed from the vacuum chamber, but all containing rarer
mediums than the aërostat proper. If rarefied air be used instead of gas the
same relative proportions as regards the density or rarefication of the air in
the different chambers or compartments must be observed: Tubes should
pass from each of these chambers and also from the aerostat proper to the
hull of the vessel, and a separate gauge should indicate the degree of density
or rarefication in each, in order that this may be known at all times with
precision. I consider that by proper precautions being taken in this. way
joined to the use of the stove or fire-place and chimney, which are described
under the 4th claim, that even gas rarefied by heat may be used when it is
required to ascend to a great height, but in this case 'nitrogen gas should be
used for the outer envelope, and a sufficient quantity of nitrogen should,
be kept in any convenient place, so that a jet may be made to act against any
part in case of accident, and these precautions will be advisable in all vessels
although not equally necessary. The vessel should be furnished with exhaust-
ing syringes or with contrivances formed to a certain extent like bellows. I
prefer the latter, which I form very nearly like ordinary bellows, a pipe from.
the bag conveying the air into the bellows, and it is discharged when so
required under the vessel through the nozzle, and by this means the bag can
be more perfectly emptied. Syringes or bellows may also be used in a similar.
manner to draw off any gas which might otherwise remain in the bag when
gas has been admitted, and afterwards returned to the aerostat proper, as far
as this can be done by the means already described. In the latter case the gas
must pass through the nozzle of the bellows or from the syringe into a pipe
communicating with the aerostat proper; either bellows or syringes may also be
used to force atmospheric air into the bag and so increase the density, and
consequently the weight when it is desired to descend. When syringes are
used I form them of pieces of bamboo or light wood, with very thin metal
lining, and they may be strengthened by light steel hoops on the outside; I
work the pistons by means of screws or racks and pinions; I find it most
convenient generally to place them in positions nearly horizontal. It is not
my intention that the exhaustion should be kept up constantly to an extreme
degree in the vacuum chambers; they are principally intended as a means of
giving the vessel an impulse upwards or forwards when more than ordinary
force is required or at any particular moment, and to give a more perfect com-
mand of the movement of the vessel by the possession of such a power, capable
of being applied at any moment or modified at pleasure; but under ordinary."
circumstances, after the vessel has attained sufficient height, it is advisable to
lessen the strain on the material as much as possible. I consider it advan-:

page_text: tageous to make use of vacuum chambers with medium chambers above them
on a similar principle for the, wings and tail, and also for the large and small
parachutes, but they are not absolutely necessary; they may even be used for
the scapular sail; they may, however, be dispensed, with altogether, both the
aerostat and wings and all other parts of the apparatus being capable of
being used without these vacuum, and medium. chambers; but I consider that
they will add very considerably to their efficiency. The transverse section of
the wing, Figure 4, and the section Figure 16, shew the position of the
vacuum and medium chambers which I consider most advantageous, but I do
not confine myself to this precise form or arrangement; they are indicated by
the same letters as the larger chambers; their positions in the 'tails are shewn
in Figure 12. When used for the scapular sail they are placed in a similar
position to the latter. In the parachutes they occupy the part immediately
above the stretchers which serve to support the lower surface of the vacuum
chamber, the material being strengthened by the addition of parchment or
other strong material, and also supported by a net work and cords within. In
the small apparatus the vacuum and medium chambers of the wings may be
formed in a manner somewhat similar to those of the parachute,; so that they
will open or become distended when the wings are opened, and close when the
wings are closed. Screws or other mechanical means may be used to assist in
opening them, as there will be a certain resistance from the atmospheric
pressure without, if no air is admitted; or the air may be allowed partially to
enter and be afterwards exhausted by means of an air syringe or by a con-
trivance resembling a bellows, which is more conveniently adapted to the
apparatus than-ar syringe. The upper part of reach of these chambers may be
sustained in the parachutes and other parts of the small apparatus by ribs of
whalebone, or steel, or flat pieces of elastic wood, but the trellis work and
bladders or bags as described are the most suitable in all cases in which the
apparatus is sufficiently large; a net. may be substituted for the trellis work,
but it is not so perfect; if the.net is used, elastic india-rubber cords are the
most suitable material. I consider it advantageous to place a funnel termi-
nating above with a valve opening inwards, and with a bell mouth below
passing through the vacuum and medium chambers, and the upper chamber
containing atmospheric air in the large parachute; the valve' permits the air
to pass downwards whenever the pressure is greater above than below, but
does not permit it to escape upwards except when opened by pulling a cord
which can be done when. descending, or at any time it may be desired. I
form the funnel with a bell mouth below in order to permit the air to pass
into it more freely from below. I consider that the air will be considerably

page_text: compressed within this tube or funnel by the motion of the parachute, and
that so long as the valve at top is not permitted to open upwards, it will
tend to increase the ascensional power. I consider it advantageous to place
similar funnels passing through the vacuum and medium chambers of the
wings with valves similarly constructed, and they may even be used in the tail
and scapular sail, or in any part of the apparatus found suitable, but they
are not necessary. These funnels are shewn in the transverse section of the
wing, Figure 4, and also in the section of the wings, Figure 16, where they
are indicated by the letter i. I make use of a vacuum chamber for the pilot
boat, which is described under the 4th claim, and represented in Figure 17;
one of them B is used to facilitate the descent, the atmospheric pressure
acting downwards when it is desired to descend, but the pressure can also be
made to act upwards while sailing or flying by exhausting the air from the
lower part B', and allowing the upper part to collapse. The upper part B. is
formed of silk or other suitable material doubled, with parchment or other
strong material placed between and united in the manner already described,
and hoops are sewed in the material in such a manner that they serve to keep
it distended, as shewn in Figure 17. When the pilot boat is suspended or let
down from the vessel, and the strain made to act on the cords v, v, these cords
are attached to the hoops w, w, and pass from thence to pulleys or to axles
fixed in the hull of the vessel from which they again pass down to windlasses,
which are placed in the pilot boat, and by this means the vacuum chamber is
distended while the pilot boat is descending, or so long as it is desirable that it
should be so. If it is at any time desirable that it should be allowed to collapse
while the pilot boat is suspended from the vessel, this is effected by slackening
the cords v, v, and making the cords x, x, sustain the weight of the pilot boat.
When the pilot boat rests in its place in the centre of the hull, as represented
in Figure 12, where it is indicated by the letter P, this part remains collapsed,
but the air may be exhausted from the lower part as already mentioned,
against which the atmospheric pressure then acts upwards.
Fourthly, my improvements have reference to the general form and arrange-
ments of the hull and the parts immediately connected with it, but more
particularly to the pilot boat, the vacuum chamber of which has been already
described. I give it this name, as its use is to descend before the vessel, and
bring it down safely. Figure 17 is a vertical section of the pilot boat; the
lower part is seen in Figures 11 and 15; it is the same in all forms of aerial
vessels which are used in combination with aerostats. The part y is of a
cylindrical form, and is occupied by the persons who descend in the pilot boat,
whose office it is to throw out grapnels and attach the pilot boat firmly to the

page_text: ground, and then draw down the vessel by means of the cords which are wound
round windlasses which are placed in the pilot boat, as already mentioned.
The pilot boat is of the most solid construction possible, and as much as
possible of the disposable weight, such as spare cordage, provisions, &c., should
be placed in it, and as many persons as can conveniently do so should descend
in it. In order to effect the landing, it should be furnished with four wind-
lasses, two for the cords v, v, which are attached to the hoops of the vacuum
chamber, and two for the cords x, x, which serve to sustain the weight of the
boat independently of the vacuum chamber, when required. The object of
appropriating two windlasses to each with separate cords is to balance the pilot
boat more perfectly while descending, and also to draw down the vessel more
effectually and with greater facility, as it is sometimes advantageous during &
strong gale of wind to draw down the vessel principally by the cords on the
windward side. The pilot boat can also be lowered to any extent required at
any time while the vessel is sailing or flying, if found necessary or expedient in
order to steady the vessel, and the cords on the windward side can in this case
also be straitened more than those on the leeward side. When this is found
suitable its progress downwards can be arrested at any moment, or it can be
drawn up again to the vessel whenever it is desirable to do so by means of the
windlasses, the axles of which must be furnished with ratchet wheels and
detents so disposed that the points of the detents can be engaged or disengaged
as may be required.
The part y, which is occupied by the persons who descend in the pilot boat,
is set upon springs, and the upper part is attached to the part B either by
springs or by straps of elastic caoutchouc, by which means the shock is lessened
when it touches the ground, although this may be effected to a considerable
extent by means of the windlasses and suspending cords. Springs must be
used only to connect the part y with the outer portion, as the latter must rest
on the ground in the most solid manner possible, and for this reason I form
the lower part in a manner having a certain resemblance to two sledges cross-
ing each other; the form of one of these is seen in the section, Figure 17; the
bottom of the pilot boat is seen in Figures 11 and 15. I consider this form
the most advantageous in order to rest in a solid manner on uneven ground, as
this is a contingency for which preparation should be made, and the four
points z, z, projecting in different directions, two at least of these will always
have a tendency to check the progress of the pilot boat, except when two of
the rollers, indicated by the letter d, Figure 11, are let down, the object of
these being that those attached to either of the sledges can be lowered so as to
roll along the ground. When this is desirable they are attached by joints, and

page_text: when lowered they are fixed in a position a little lower than the bottoms of the
sledges, so that, under these circumstances, the bottom of the second sledge
does not interfere so as to oppose the progress of the boat. Anchors or grapnels
are attached to the points z, z, as represented in Figure 17. I prefer setting
these under springs nearly similar to those used for the wings, except that they
are so arranged that they cause as little upward spring as possible to the pilot
boat when they are liberated; their object is to cause the flukes of the anchors
to strike and enter the ground more effectually; these springs are, however,
not necessary. The persons descending in the pilot boat must also be provided
with grapnels, which may be of the ordinary description, but I prefer forming
one or more of them with the flukes attached to the stem by joints, and pressed
downwards by springs in such a manner that the flukes shall strike downwards
when liberated in a manner bearing a certain resemblance to the action of the
talons of a bird, separate cords being attached to each of the flukes, and all
these being collected in a small sheath, and so arranged that the flukes can be
raised or
permitted to spring downwards by either fixing these cords in any
convenient way, or letting them go when it is desired that the flukes shall act so
as to enter the ground or seize any object: An additional advantage derived from
the use of the pilot boat, and from arranging it in such a manner that it can be
lowered at any moment from the vessel, is; that the stove or fire-place which I
consider useful under all circumstances, but which is indispensable if rarefied
air or gas rarefied by heat be used, being placed in the inner compartment y
of the pilot boat; either this part or the entire pilot boat can be lowered at
once in the event of danger from fire, or even sacrificed in an extreme case.
The most perfect arrangement is to unite the inner compartment y to the
outer in such a manner that they can be disunited' when so required. The
stove is indicated by the letters, Figure 17, and is also seen on a smaller scale
in Figures 11, 12, and 15, where it is indicated' by the same letter. "The
lower portion of the pipe or chimney p fits into that part c which is made fast
to the hull, but it can be slipped out when the pilot boat is required to be
lowered; it may be attached in any convenient way which will admit of this,
but by forming the lower portion of such a length that it may pass a sufficient
distance either inside or outside of the upper portion, it cannot slip so long as
the pilot boat occupies its position in the centre of the hull. When the air
or gas in the aerostat is not required to be heated, this chimney is not abso-
lutely necessary, but I consider it desirable; the arrangement represented in
Figure 15 is that adapted to heating gas, and I. consider this the most suitable
'for aerostats of this class. When the gas in the aerostat is not required to be
heated, the valves' at the entrances of the pipes p'; p', must be closed, and the

page_text: n is
heated air will then ascend directly through the top of the pipe or chimney t,
and I consider it will have a certain effect, although it may be a trifling one, in
lessening the atmospheric pressure above.. A valve must also be placed within
the chimney at the point q. It is intended that there should be at least four
pipes, such as those indicated by the letter p' in the section, Figure 16, and
there may be a greater number, but only two can be seen in this view. The
pipes p', p', are closed, so. that the heated air passing through them has only
the effect of raising the temperature of the gas in the aerostat and afterwards
passes through the top of the pipe t. If rarefied air is used, the heated air
must be allowed to enter the aërostat, and in this case the pipes p, p, must be
formed in a different manner so as to admit the heated air, and the upper part
of the chimney must be closed by means of the valve. This part is, however,
useful even in this case, as by means of it the heated air may be allowed to
escape at any moment instead of entering the aerostat.
an outer tube,
which is filled with nitrogen gas; this may be continued the entire length of
the chimney or otherwise. I consider it advisable to cover the stove, and either
the entire chimney or those parts most exposed to risk from fire, with asbestos
cloth, but this is not absolutely necessary. L, L, Figure 12, is. the upper part
or covering of the hull, which may be formed of light boards or any light
material. I prefer this form, as I consider it best adapted to diminish the
atmospheric resistance in front. One or more elastic tubes partially filled with
any material which can be made to slip easily from one extremity to the other,
are placed in the hull of the vessel in such a manner that the extremities of
the tubes can be made to pass beyond either side of the hulls, and so assist in
righting the vessel or maintaining its equilibrium when acted on strongly by
the wind or by the current of air produced by the action of the wings or any
other cause, and these tubes may also be made to serve to raise or lower the
head when so required. I prefer placing one of these tubes in front of the
pilot boat, and another behind, each tube being attached in the middle to the hull
in such a manner that the extremities of the tubes can be moved in any direc
tion required with the greatest facility at any moment. Apertures are formed
in as many parts of the hull as convenient, through which lamps or lights of
any convenient. kind may be let down during the night, in order more clearly
to shew the nature of the land or water over which the vessel may be passing.
but the lamps placed in the arrow heads or leading points of the aerostat above
should, generally speaking, be sufficient, for this purpose.
Fifthly, my improvements consist in the construction of a landing place for
-aerial ships, with a railway conducting from thence to a building capable of
receiving them.. These are by no means necessary for the purpose of effecting
C 2

page_text: a safe landing, which I consider may be done by means of the improvements
already specified in any tolerably open country; but I consider that a building
capable of containing the aerostat with its apparatus complete, and having
folding doors at one side sufficiently large to admit of the aerial vessel entering
and departing, will be necessary for the full efficiency of my system in a prac-
tical point of view; and when it is required to conduct the aerial vessel into
this building, a railway will become necessary for this purpose. The most
advantageous position for the landing place is either a plane in a level country
or an elevated position in a hilly one when such can be obtained free from
trees, buildings, or other obstructions; a circular space should be levelled, or
partially so, as far as practicable, according to the situation, and it should be
surrounded by a paling, both the uprights and cross bars being perfectly round
and smooth, and it is advantageous that they should be painted white in order
to be more conspicuous. Outside these I place lights which may be of any
convenient kind; they are placed all round the outside of the paling, and
covered above with glass, and furnished with reflectors so arranged that the
light may be as conspicuous as possible to aeronauts sailing above. The glass
roof or covering should not be higher than the top of the paling. A second
paling or inclosure may be constructed round the lights. The railway or guide
rails are set in the inside of a hollow trunk, but there are three lines of guide
rails within the tube, one at bottom and two at top, one being at each side of
the longitudinal opening. The principal object of the tube or tunnel is to
prevent the vessel being drawn upwards by the aerostat, or impelled sideways
by the action of the wind against it. I prefer having two of these tubes or
tunnels in order to effect this object more perfectly; each of them is furnished
with a rope, the object of which is to keep down the vessel and steady it, and to
afford a simple means of drawing it forwards, part of each of these ropes being
wound round windlasses which are turned by the hands of the aerial navigators,
and one end of each rope being made fast inside the building, and the other at
the landing place, the vessel is drawn forwards by turning the windlasses. The
hollow trunk is formed with a longitudinal chase or aperture, through which three
tongues, which may however be united in one, depend vertically from the rail-
way car, on which the hull of the vessel is placed. A machine bearing a certain
resemblance to a dynamic traveller or mechanical horse, which is made to fit
in the interior of the tube, runs on castors which turn within the guide rails, or
both within and at each side of the guide rails. I prefer the latter arrange-
ment. Other castors run in a similar manner within, or both within and at
each side of the guide rails above; the latter are set at each side of the longi-
tudinal opening, which is as narrow as is consistent with allowing sufficient

page_text: substance or thickness to the tongues or tongue. The ropes, pass under wheels
whose axles are fixed on the foremost and hindmost tongue, or on the foremost
and hindmost parts of the long tongue if formed in one; the object of this
arrangement is more effectually to keep down and steady the vessel. The rail-
way car is furnished with wheels which run outside the tubes or tunnels; the
railway car should be low, and the hinder part should be formed in such a
manner that the hull of the vessel can be made to slide upwards on it with
great facility.
What I claim is,-
First, the construction of wings with a horizontal tail or rudder, the stems
or bases of which are set under springs, and which act on the air by the recoil
or re-action of these springs, this principle being more particularly applied to
the wings, but the tail being capable of being worked in a similar manner when
suitable, and the construction and use of the oars and of the alæ spuriæ, all
being raised more slowly than they strike downwards, and the different appli-
cations and modifications of these and other parts of the apparatus, as described.
Secondly, the different forms and modifications of the aerostat, as described.
Thirdly, the construction of vacuum chambers in such manner that they
shall be acted on by currents of air on their lower and hinder surfaces, or on
any parts which it is suitable should be so acted on, and at the same time be
relieved as far as possible from the direct atmospheric pressure on their upper
and foremast parts, or any other parts that it is expedient should be so relieved,
and the applications and contrivances for effecting the same, and the different
modifications of the principles, as explained.
Fourthly, the improvements in the form of the hull of the vessel, and the
parts and apparatus immediately connected with it, and especially the form,
construction, and use of the pilot boat, as set forth.
And, fifthly, the plan and construction of a landing place with lights or light-
house and a railway, as set forth.
30 SPECIFICATION in pursuance of the conditions of the Letters Patent, filed by
the said Benjamin O'Neale Stratford, Earl of Aldborough, in the Great.
Seal Patent Office on the 29th July 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, BENJAMIN
O'NEALE STRATFORD, Earl of ALDBOROUGH, of Stratford Lodge, in the County
35 of Wicklow, in Ireland, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirtieth day of January, in the year of our Lord

page_text: One thousand eight hundred and fifty-four, in the seventeenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Benjamin O'Neale Stratford, Earl of Aldborough, Her special licence
that I, the said Benjamin O'Neale Stratford, Earl of Aldborough, my executors,
administrators, and assigns, or such others as I, the said 'Benjamin O'Neale
Stratford, Earl of Aldborough, my 'executors, administrators, and assigns,
should at any time agree with, and no others, from time to time and at all
times thereafter during the term therein expressed, should and lawfully might
make, use, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for "IMPROVE-
MENTS IN AERIAL NAVIGATION," upon the condition (amongst others) that I, the
said Benjamin O'Neale Stratford, Earl of Aldborough, by an instrument in
writing under my hand and seal, should particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to be per-
formed, and cause the same to be filed in the Great Seal Patent Office
within six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that' I, the said Benjamin O'Neale Stratford, Earl of
Aldborough, do hereby declare the nature of my said Invention, and in what
manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement thereof, reference being had to the
rawings hereunto annexed, that is to say:
First, my Invention consists in the construction of wings, in such a manner
that they compress the air by percussion, and force it under the concave part
of each wing, currents of air being also impelled towards the same parts
by fanners, which act on the same principle as that on which I believe the
alæ spuriæ or spurious pinions of birds act, the centre of pressure, caused by
their combined action, and also by the current or currents of air which pass
under the wings in consequence of the progression of the aerial machine or
vessel, creating a support under each wing, and consequently at each side of
the weight to be raised or sustained; the air is also compressed under the
weight itself, but I believe that the mechanical force acts more especially at
each side. I effect this object by raising the wings slowly, and by making
use of the advantage thereby obtained to accumulate force by every available
means, according to the size of the aerial machine or vessel; a combination of
springs being forced upwards as the wings are raised, the re-action of which
causes them to perform the stroke downwards, which is, as nearly as possible,
instantaneous; the only diminution of velocity arising from the resistance of
the air below on which they act, and from the unavoidable friction of the cords

page_text: and machinery, which is reduced to the lowest possible point, by all known
means suitable to the circumstances; the extremities of the wings, and also the.!
alæ spuriæ, striking the air by distinct actions, in addition to the impulse of..
the entire wing of which they form parts, and with which they necessarily
move, in a manner as nearly as possible similar to that in which; I believe,- a!ı
bird's wing is moved, the carpus, metacarpus, and phalanges to which; the <
primary feathers are attached, being capable of acting, as I believe; indepen-
dently of the humerus and cubitus, either simultaneously with those parts .or <
otherwise; the alæ spuriæ having: also a distinct action, and I believe a very..
important one in the bird's wing, I cause the extremity of ther wing: to
perform the stroke at the same moment that the entire wing: strikes down-
wards, this combined action.forcing the air-much more effectually under the
wing, and also under the weight to be raised or sustained, more especially: as
the extremity of the wing would; otherwise be bent upwards during the stroke:
by the compression.of the air underneath; but it may also be made to strike
during the rising of the wing; I prefer arranging the mechanism so that it
shall strike once, twice, or a greater number of times during the rising of the
wing; the ale spurice must always strike during the rising of the wing, but it
also strikes simultaneously with the stroke of the wing. The details. of the
arrangements are represented in the accompanying Drawings. When Irspeak
of raising the wings slowly, I mean.in comparison with the downward stroke..
Imake use of the term percussion to express the instantaneous action of the
wings in the stroke-downwards, as distinguished from that, of ordinary:
machines. I believe that a bird. is sustained in the air by the excess of;
pressure-against the. lower surface of the wings and body, beyond that on the
upper surface; but although the, density, of the air under the entire of the
lower surface must be greater than: above, I consider that the principal force
is derived from the centre of pressure occurring under, cach wing precisely at
that point where it acts with the greatest mechanical advantage, and I believe,
this, to be one of the essential points in which the principle of flying or sus-'
taining and moving a body, in the air, differs from that of, floating- or moving
through the water, and I believe that each successive stroke of each wing
creates to a certain extent a fresh "point d'appui,or support, by the com-
pression of the air.under the wing and under the body of the bird, the strokes.
of the alæ spuriæ producing. the same effect in a smaller degree, and the
current or currents of air..produced by the progress of the bird contributing to
the same object, and the wind also frequently assisting. I believe that 'some
birds, more especially take advantage of the wind; using their wings: to a
certain extent: like. sails, and by this means flying, with less labour and also

page_text: with less noise, as seems to be the case more particularly with owls; but I
believe that the real supports, or at least the principal points of support,
which sustain the bird, are always under those parts where the centre of
pressure occurs under each wing; I believe that if the density of the air under
these points could be ascertained while the bird is flying, it would be found
sufficient, according to clearly defined scientific principles, to support the bird;
and I believe that both the formation of the bird's wings, and their action, and
also that of the alæ spuriæ, tend to concentrate the force of the pressure
precisely under those points where the greatest mechanical advantage is
derived from the support; for although the arm, as it may be termed, of a
bird's wing, or that part composed of the bones and sinews, is in advance of the
centre of gravity of its body, the centre of pressure occurs, as I believe, under
the hollow part of the wing behind the arm; and I believe that a line drawn
through the centre of gravity, and across the body of the bird at right angles,
with one drawn also through the centre of gravity from the head to the tail,
would pass precisely through those points under the wings where the centre of
pressure occurs under each. I believe that the alæ spuriæ or alulæ spuriæ as
they are sometimes termed, although some ornithologists seem to consider
them as merely covers for the bases of the primary quills, really act as fanners
to the wings, and perhaps even to a certain extent as propellers. I believe
that the primary feathers of the wing may be considered as acting the part of
oars, so far as regards propulsion, but that they at the same time compress the air,
and force it under the hollow parts of the wings, which latter are, as I believe,
principally useful as parachutes, containing the air so impelled, that is to say,
sufficiently so for the purpose, although all parts of the wing assist to a certain
extent in performing the stroke, when the entire wing is moved from the
shoulder. Birds appear sometimes to strike with the back part of the wing
when rising, but this is not the ordinary action of the wing while flying, and I
consider the principal office of this part is that of a parachute; I; however,
believe that the back part of the wing, when in certain positions, also acts the
part of a sail to a certain extent, and the mechanical wings, as I form them,
can also be made to serve a similar purpose. I consider that the failure of
the attempts hitherto made to raise or sustain a body in the air by means of
wings, are principally owing to ignorance of the fundamental principle on
which alone wings can be made available for the purpose, and that by which
they perform this office for the bird'; that is to say, by impelling the air under
the wings and under the weight to be raised, instead of from it, as the oars of
a boat, or the paddles of a steamer, strike the water. I consider that the
stroke of the wing would not be efficient, if it were not raised more slowly

page_text: than it strikes downwards; it is well known that the resistance of the atmo-
sphere to any surface is in proportion to the speed with which the surface is
moved against it; and in addition to this, a comparatively slow motion of the
wing while rising, permits the current or currents of air passing underneath
more effectually to fill the concave part. When the wing is raised to the extent
required, it is then caused to strike downwards with an instantaneous motion,
before the air has had time to escape, so to speak, from the stroke; I consider
that it is only a reciprocating motion that can produce this effect, and that a
continuous circular motion, like that of paddles, or even the action of a screw,
is altogether unsuitable, and incapable of producing the necessary effect on the
air. I believe that the effect is produced in a great measure by the sudden or
instantaneous change in the direction of the impulse, to a direction directly
opposite, which greatly increases the resistance; and different currents of air
being impelled towards the same points, or passing towards those points, by
reason of the progress of the bird or of the machine or vessel, cause violent
compression at those points. As regards the steering, I consider that it
depends chiefly on a principle which does not appear to have been ever acted
on or even defined, theoretically at least, with sufficient distinctness, although
some of the facts, which I consider afford proofs of the principle, have been
to a certain extent remarked, which are, that all birds possessing great powers
of flight, evidently fly with very little labour or muscular exertion, and that
some fly almost always with a sailing motion and little noise, and with one
wing more elevated than the other. I believe that this faculty depends on a
principle, which all birds avail themselves of more or less, in guiding and
especially in turning themselves in the air; I believe that when the wings are
in this position, that is, one wing elevated and the other depressed, that both
wings together act to a certain extent on the principle of an inclined
plane placed across the body of the bird, its descent on the side of the
depressed wing being prevented by a slight action of the wings or of the
spurious pinions, by means of which the air underneath is compressed and
caused to act against the under surfaces in a manner somewhat similar to
that in which the wind acts against sails, but with this difference, that it
can be made to act at any moment in any direction desired, and the bird
is even enabled to set its wings, as it were, to a certain extent against the
wind when it blows from an unfavorable point, in consequence of their form
and their stiffness, which enables them to preserve that form independently
of the wind, which, when it impinges on the upper surface, glides off to a
certain extent, comparatively at least, and is impelled under the concave sur-
face by the action of the wings or of the spurious pinions, and by this means

page_text: the bird is impelled in the direction it desires. I am aware that the principle
of the inclined plane has been frequently suggested as suitable to aerial
navigation, but not, as I believe, in a manner similar to that which I have
described; and I only claim it when applied in the manner I have mentioned..
If the action of a bird's wings be remarked when turning or suddenly changing
its direction in the air, it may be perceived that it raises the wing on the side
from which it desires to turn, and commonly.strikes with that wing, at the
same time holding the other wing in a horizontal position, or inclining it
slightly downwards, or drawing it backwards, or partially closing it to a certain
extent, according to circumstances; and it is evident that this principle can
be applied to resist or modify the effect of an unfavorable wind, which would
otherwise drive an aerial vessel out of its course; the action of the .wing on
the leeward side being capable of producing an artificial current to counteract
or modify. the effect of the wind on.the windward side. This is only an appli-
cation of the well-known principle of the composition of forces, which will
determine the course of the vessel in an intermediate direction between the
two impulses. When the wind is not too directly opposed to the vessel's
course, the desired point may be reached by working both wings on a principle
similar, to a certain extent, to that on which a boat is rowed across a river
where there is a strong current; but in no case having any analogy to the
tacking of a sailing vessel, in which latter case the action of two separate
elements at the same time produces the effect. But I consider that it will
generally be much more suitable, during a strong gale, to work the leeward
wing only, the windward wing being held steadily in a horizontal position, or
slightly inclined downwards, if the wind be violent or blowing in a direction
very much opposed to the vessel's course; but when the wind is on the quarter
(to use the term common in navigation) and not too violent, I consider that,
the windward wing may be raised and set steadily at any suitable elevation,
and by this means advantage may be taken of the impulse of the wind, the
leeward wing being worked at the same time, so as to keep the vessel in its
true course; or, it may sometimes be advisable to work the windward wing
gently, or to cause it to perform half or quarter strokes, working the leeward
wing at the same time with its full force. I consider that an aerial vessel will
arrive much more quickly at its destination, independently of saving the wear
and tear of materials, by proceeding on this principle than by laboring in
direct opposition to the wind, even supposing the latter course to be prac-
ticable, as more will be gained by increasing the speed than will be lost by
increasing the distance. In a calm, it will of course be necessary to work
both wings alike, except when it is required to turn or alter. the direction. As

page_text: regards the principle of rising or descending, in order to attain a position
where a favourable current may be found, the greatest facilities are afforded.
by my system, by which I can cause the vessel to rise or descend at 'pleasure,.
without loss of either gas or ballast. The particulars as regards the means.
used for this purpose are described under the second and third claims. But
this facility does not supersede the necessity for finding means of guiding the
vessel in contrary winds, as.a wind exactly favorable can seldom be calculated
on for an entire voyage, or at least it could not suffice to bring the vessel to
the precise point required: And I consider it almost always advisable to.
ascend more or less against the wind, or with the vessel's head to the wind, as
the wind elevates the vessel more effectively when acting on it in this way,
and the danger of being carried forwards with too great speed or violence is also.
avoided till all obstacles are fully cleared, which might otherwise cause the
destruction of the vessel, as so 'frequently occurs to ordinary balloons before.
they attain a sufficient height to surmount them. When the vessel has arrived.
at a sufficient elevation; I wind. gradually into the desired course. When
descending, especially during a strong gale, I turn the vessel's head to the,
wind, in order to avoid being impelled forward during the operation of effecting.
a landing; and for this object also it is advisable to describe a gradual curve,
or, in some instances; a succession of curves, as birds very commonly do before.
alighting. I believe that. birds' make use of the tail as an inclined plane, by.
elevating. one side or the other, the inclined plane acting sideways as in the.
case of the wings. It is well known that birds make use of the tail when
rising or descending: but it does not appear to have been discovered, or it does
not at least appear to have been clearly defined, that they also guide themselves.
in a lateral direction by elevating one side or the other; and this motion of the.
tail may also be perceived when they are turning or circling; they appear
sometimes to move the tail also sideways from the base, but I believe that a
lateral change of direction is effected principally, so far as the action of the
tail is concerned, by using it as an inclined plane, in the manner. I have men-
tioned. I believe that birds guide themselves chiefly by means of their wings,,
but I consider that it is by using both the wings and tail as inclined planes, on.
the principle that I have explained, that they are enabled to fly with so little
effort as the greater number of birds do; and I consider that the application
of this principle supplies one of the principal means by which, aerial navi-
gation may be accomplished. without, that enormous exercise of power which
seems hitherto to have been considered necessary, and which it has commonly
been supposed impossible to unite with sufficient lightness of material. I
consider it essential that the weight to be raised should, be placed on springs,

page_text: against which the bases of the wings and also of the tail should press upwards,
one part of each spring being pressed upwards by the action of the wing while
rising, and the other part being so pressed while it is performing the stroke
downwards; and the springs, against which the base of the tail acts, are pressed
in a similar manner when the tail is moved. All these springs are so con-
structed and arranged, that each portion of the spring even exercises a certain
upward pressure during the recoil; that is to say, when it is no longer pressed
upwards from below. Both the wings and tail act on the principle of the
lever, and the centre of gravity of each lever is at the opposite side of the
fulcrum or pivot from the weight to be raised or supported. Figures 1, 2, 11,
15, 17, 19, 21, and 24, shew the lower surfaces of different modifications
of wings. Figures 1, 11, 17, 19, and 24, shew also the lower surface of the
tail or rudder in combination with the wings. In Figures 11, 17, and 19, an
additional sail, or what may be termed a second rudder or tail, is represented,
which is placed over the first, but its base is set under springs, in a manner
similar to the lower one. I consider this arrangement the most perfect for
combinations with an aerostat, but the upper rudder or tail is not absolutely
necessary. Both of these can be made to act as inclined planes either laterally
or vertically, and the lower one, or even both, may be made to strike down-
wards against the air when the vessel is rising, and so increase the ascensional
power by compressing the air underneath, as I believe birds commonly do,
especially pigeons. These observations also apply to the tail represented in
in Figure 1, and that represented in Figure 24. It is evident, that even when
an aerostat or envelope containing gas or rarefied air is used, it is nevertheless
advisable to increase the ascensional power, independently of the aerostat, by
all available means, as by so doing the size of the latter, and the consequent
resistance of the atmosphere to its progress in any desired direction, may be
diminished. I consider that the mechanical action of the bases of the wings
and tail upwards against springs, will contribute very materially to this object,
in consequence of the elastic nature of the atmosphere, which makes it
essential, as I believe, that a springing motion should be communicated to the
body to be raised, which I consider will have much effect in counteracting.
the tendency to fall during the intervals between the strokes of the wings.
And even the variable action of the wind, which appears to present one of the
greatest difficulties, but which seems really to be caused only by the suscepti-
bility of the atmosphere to be acted on by apparently inadequate means,
renders this arrangement essential, as I believe, in order to sustain the body
during the lulls which commonly intervene between gusts of wind as well as
between the strokes of the wings. I also consider that the peculiar nature of

page_text: the atmosphere requires that it should be acted on by an elastic force. In
very small machines, intended only to be used by a single person, I term that
part which immediately sustains the person and apparatus, the seat or saddle;
in large vessels I term this part the hull of the vessel. The framework of
the wings, and also that of the rudder or tail, is formed principally of a species
of very light canes or reeds, which grow on the banks of the Mediterranean,
where they are well known, and are commonly used by the peasants as fishing
rods. I strengthen them by means of prepared ox muscles or sinews, called
in France "nerfs de bœuf." They are well known in Paris, where they are
commonly used by coachmakers and mechanics. They should be stretched
evenly along the canes or reeds, and attached to them by means of glue or
copal varnish, or other adhesive substance. They should afterwards be covered
with silk or other light material, and varnished. When the wings are of a large
size, these canes or reeds may be further strengthened by boring them and
filling the hollow part with caoutchouc in a liquid state, and then inserting a
steel rod in each, or these steel rods may be attached to the outside; these
steel rods should be tempered like fencing foils, and I prefer a form in most
instances nearly approximating to that of a fencing foil; in some positions,
however, some parts of these rods require to be flatter in proportion. The
canes used for the fore part of each wing should be stronger than those used
for the hinder part; and when the wings are of a large size, bamboos may be
used instead of the very light canes or reeds I have mentioned for the fore
part of each wing. a a, Figures 1, 2, 11, 15, 17, 19, 21, and 24, are boxes or
sheaths, containing cords, which may be of good ordinary material, but I prefer
caoutchouc, prepared so as to have the greatest elastic force possible, but I
do not claim any improvement as regards the preparation; these cords are
twisted round the stems of the wings and the bases of the lateral shafts of
the tail, in a manner common in workmen's tools, especially small frame saws;
the stems of the wings, which are formed of wood or of wood combined with
canes or bamboos, and strengthened by steel rods, are attached by means of
these cords to the lower part of the seat or hull of the vessel, and they are
set in such a manner that they cause the wings to spring strongly downwards,
when not drawn in the opposite direction; the parts b, b, Figures 2 and 3,
acting as the short arms of levers, and pressing upwards against springs when
the wing strikes downwards, and the parts b', ', pressing upwards against
other parts of the springs when the wing is raised. These springs are formed
of thin flat pieces of elastic wood, strengthened by the prepared ox muscles or
sinews already mentioned, with thin flat steel springs wound or coiled round
them; the extremities are bent upwards and lapped one over the other at

page_text: top, where they are attached to the framework of the sent, or of the hull of the
-vessel; and I consider it advantageous to stretch a band of elastic caoutchouc
round each of these springs. The principle is the same as regards the tail, but
the modification slightly different.
i
Figure 3 is a side view of one of these springs; they are set obliquely, the
upper part being inclined inwards, and I prefer inclining them also forwards as
much as possible, in order that the pressure may act as much possible in that
direction; but the latter inclination is not necessary. d; Figure 3, is a steel
spring, or combination of springs, which presses downwards against that part
of the stem of the wing indicated by the letter b', so as to increase the force
of the stroke of the wing, and a similar one presses against each of the
lateral shafts of the tail; the cords already mentioned are twisted round the
part marked a; the canes or reeds or bamboos, which, with the steel rods and
their covering form the wing, are attached to the stems; these and also all
other parts that require it, are strengthened by the prepared ox muscles or
sinews already mentioned. I term the principal bamboo or cane of each
wing with its oar, the beam, and the others the shafts; I apply the former
term also to the principal oar in the more complicated form of wing repre-
sented in Figure 2, although in this latter form it is not attached to the bamboo
or cane. I term the parts e, e, Figures 1, 2, 11, 17, 19, and 24, the oars; they
are formed of elastic wood, strengthened by steel rods or foils. I have repre-
sented the more simple forms of wings in combination with the aerostats, Figures
11, 17, and 19, as I consider that, from the simplicity of their construc-
tion, they will be found most useful in practice for aerostats generally, except
when they are of a very large size, in which latter case the form of wing
represented in Figure 2 may be advantageously used; its construction is more
complicated; the oars being so arranged that they can be drawn backwards
when desirable, having their bases set on the pivots or joints f, f, they spring
forward when liberated by the re-action of the springs g, g, which are placed
between the oars, one end of each spring being attached to the oar in front,
and the other end to the oar behind it, and also by the elastic re-action of
cords or stays of elastic caoutchouc or other elastic material, which are drawn
.round sheaves placed in the fore part of each wing, and pass from thence to
the hull of the vessel. The number of the springs 9, 9, may be increased if
necessary; the best material for these springs is elastic steel; the oars are set
.with an inclination downwards, in such a manner that the extremities spring
downwards when not drawn in the opposite direction. The arrangement
represented in Figure 1, and that represented in Figure 24, are adopted, in
order to admit of the wings being closed, or as nearly so as possible when the

page_text: person is not using them, so as to permit him to walk with as little incon-
venience as possible before rising and after descending. The arrangement
represented in Figure 2, has reference to the 'more perfect steering of the
vessel, and effecting the descent with greater facility, or impelling the vessel
forward at any particular moment with the greatest speed possible; wings
formed in this manner may even be made to close partially after each stroke,
if so required, as birds commonly do, but I do not consider that this will be
found necessary in practice. The more simple forms of wings, represented in
Figures 11, 17, and 19; may be used with an apparatus adapted to the use of
a single person, but they have not the advantage of the capability of being
closed at pleasure; the tail or rudder may be made to close in a manner
similar to the tail of a bird'; and the angles of inclination of the stems or
bases of both the wings and tail may be altered, by means of adjusting screws
or other convenient arrangement, when it is considered advisable to form those
parts of the framework to which the springs are attached in such a manner
as to admit of this alteration being made at pleasure; but this is not absolutely
necessary, and the more complicated arrangement will of course be attended
by increased expense; but I prefer constructing the wings represented in
Figures 15, 21, and 23, so as to be capable of this adjustment. In the
modification représented in Figure 19, the oars are inclined backwards. The
Figures in which the aerostat is represented, are on a smaller scale than the
other Figures, as the Drawings would otherwise be required to be of a very
large size. The direction of the stroke of the wing may be more or less oblique,
but it must always direct the air under the weight to be raised or sustained.
The pieces e', e', are set in front of the beam or principal oar, in order to give
a form slightly curved or falcated to the fore part of the wing, similar to that
of most birds; by means of these, the foremost edge can also be made sharper,
and sufficient strength at the same time retained, and the cords or stays which
serve to keep the wing expanded by drawing the beam forward, are passed
over these. The same letters indicate similar parts of the wings in all the
Figures in which the wings are represented. The part k is concave, but it is
most so in the middle and hinder part of the wing, in the forms represented in
Figures 1, 2, 11, 17, 19, and 24; and in the form represented in Figures 15
and 21, it is more hollow in the centre than at the sides; this form is given to
it by bending the canes or reeds (and also the oars in a slighter degree) in this
part, or those parts of the shafts which form this part may be made of curved
pieces of wood; the stems, with the exception of the parts marked b; b. are
also curved; the part i, i, is flat or nearly so; those parts of the canes or reeds,
with the extremities of the steel rods or foils, which form the framework of

page_text: this part, are drawn upwards, when it is required to raise the oars and palms
by cords, indicated by the letter j, Figure 4, to the arched part of each shaft,
being set with their points or extremities inclined downwards, so that they
have a tendency to spring downwards, by which means this part of the wing,
which I term the palm, strikes downwards along with the oars which are set in
a similar manner, and both are liberated and permitted to strike at the same
time; and this arrangement also contributes at all times to enable the light
extremities better to resist the pressure of the air underneath, which would other-
wise have a tendency to bend them upwards; these cords pass over small pullies,
or over one sheaf and under another, which is the most suitable arrangement.
The position of these pullies is indicated by the letter k, Figure 4, and they
are conducted from thence to the arm of a crank which is shewn in Figure 10,
and indicated by the letter 1, to which the cords which serve to raise the oars
are also attached, and by this means they are drawn upwards along with the
oars, and permitted to spring downwards with the oars when they are required
to perform the stroke; the tensions of the different cords which are attached
to this part are so arranged that no strain is caused on the extreme points.
Figure 4 is a section of the wing cut across between two of the shafts in the
middle part; small notches may be cut in the blades of the oars or of a certain
number of them, and valves placed underneath in such a manner as to permit
the air to pass downwards, but not upwards. I believe that the small notches
or sinuosities observed in some of the principal feathers of most birds possess-
ing the greatest powers of flight, have this effect to a certain extent. In
those forms of wings in which the oars are not required to be closed, I prefer
setting them at a certain distance one above the other, the hinder oar being
always above that in front of it, and placing valves or flaps between them in
such a manner that the air can pass' downwards but not upwards, and this
may even be effected in the more complicated form represented in Figure 2,
by setting the springs 9, 9, with a suitable inclination for that purpose. In
the more simple forms, the oars are kept separate by means of steel stays. I
place valves under the shafts which are behind the oars, or a certain number
of them, which also permit the air to pass downwards but not upwards, the
hinges of the valves being attached to the shafts; the distance between the
shafts at their terminations or extreme points is greater in proportion as they
are placed farther from the fore part of the wing. I consider it advisable to
form the middle part of the wing larger or broader in proportion to the fore
part than is usual in the wings of birds; the reason is, that any length of shaft
which is manageable in one part may be made manageable also in another,
whereas in the bird nearly the entire force seems to exist in the fore part of

page_text: the wing, the feathers in that part being under the immediate control of the
principal muscles and sinews. The framework of the wings and also that of
the rudder or tail is covered with a double covering of silk or other suitable
material, parchment or steel plates, or some stiff material being introduced
between the two, and the whole is united by caoutchouc or copal varnish, or
glue, or other adhesive substance; cross stays of steel, passed through small
pieces of reed or light cane, are placed between the shafts to keep them
expanded in all forms, except those represented in Figures 1 and 24. The
wings are raised by means of cords attached to the canes m, m, Figure 12, and
to canes similarly placed in the smaller wings; these canes are sewed to the
material of which the wing cover is formed, which is silk or other similar
material. The wing covers, when an aerostat is used, are united at top to the
aerostat, and may be considered as prolongations of the acrostat. Figure 12,
in which one of these is represented, is a longitudinal section of the aerostat
with the entire apparatus combined, the whole being supposed to be cut pre-
cisely through the middle from stem to stern, one wing cover and one arrow
head are consequently seen in perspective; the arrow head is described under
the second claim. In the apparatus intended to be used without an acrostat, the
wing cover terminates in a point at top, which is inclined backwards; in this
small apparatus, which is intended to be closed, or as nearly so as possible,
when not in use, the canes which are attached to the wing covers are formed
with joints, so that these parts can be closed, or partially so, along with the
other parts of the wings; the wing covers are inflated: I prefer atmospheric
air for this purpose. The cords which are used to raise the wings may be
attached to the canes of the wing covers, either directly or by means of
systems of pulleys; the former is very suitable for a small apparatus, but I
prefer the latter for large vessels. The canes of the wing covers, or at least
those to which the cords that serve to raise the wings are attached, should be
stayed to the shafts below. I prefer forming the wing cover in the manner
shewn in the section, Figure 4, and also in the sections, Figure 16 and Figure
22, disunited at the extremity from the lower part of the wing, in order to
permit free action to the oars and the extremities of the shafts or palms; and
the stays from the canes of the wing covers should be so arranged as not to
interfere with this freedom of action. These stays may very suitably be formed
of elastic caoutchouc; they are indicated by the letter v, in Figures 4, 16, and
22; the sheaves are of light wood, and the blocks are of cork; the latter have
small apertures only at the sides, sufficient to allow the necessary play to the
cords, but no more. The tail is raised in a manner nearly similar; the tail
cover is formed of materials similar to the wing covers, except that they may

page_text: be lighter Figure 12 shews a longitudinal section of the two rudders or tails
already mentioned; pieces of flat elastic wood are used as cross stays for the
wing and tail covers. The cords which are used to raise the tails from their bases
are attached to the canes n, n Figure 12; those which serve to raise the lower
one may be passed through the upper, or both may be raised together, but I
prefer arranging the cords in such a manner that each can be moved separately;
they may be furnished with valves, but these are not necessary. The parts o; 0;
Figures 1, 11, 17, 19, and 24, are formed of materials similar to those used for
the oars, except that they are lighter, and are fixed under the lateral shafts of
the tail or rudder; these shafts are similar to those of the wings, but lighter;
the lateral shafts are stronger than the middle shafts. The cords which are
used to elevate or depress either side of the tail or rudder are attached to the
lateral shafts; these shafts are stayed to the seat or hull, the stays being of
elastic caoutchouc or other elastic material, so that the tails or rudders can be
raised or depressed at either side to any degree required; and spring back when
liberated, causing the tails or rudders to recover their original horizontal posi-
tion; the part of the tail indicated by the letter pris concave, but it is most so
in the middle; the part is flat or nearly so; this form is given to the tail in a
manner similar to that in which the same is effected in the wings. The extremity
of the tail may be made to strike" the air by an independent action, in a manner
similar to the extremities of the wings; the form of the tail may be varied "as
in different species of birds; a forked, round, or cuneated form being given to
it by making either the lateral or the middle shafts longer or shorter in pro-
portion to each other. The alæ "spuriæ are represented in Figures 1, 2, 11,
17, 19, and 24, in all of which they are indicated by the letter 'r." The fore-
most parts or oars of the alæ spuriæ are formed of thin flat pieces of elastic
wood strengthened by pieces of elastic steel, the bases" being attached to the
fore parts of the wings by ineans of cords, similar to those used to attach
the stems of the wings and the bases of the lateral shafts of the tail to the seat
or hull, except that they are much smaller and lighter; they are set in such a
manner that the alæ spurice spring downwards when not drawn in the opposite
direction; they may also be pressed downwards 'by steel springs; but these
latter are not absolutely necessary. The frames of the hinder parts of the
alæ spuriæ are fornied of light steel rods, and light canes or reeds may be used
in addition, and curved pieces of light wood may be used in the concave part,
indicated by the letter ', (Figure 2) in a similar manner to that mentioned in
the description of the wings proper. It is also advisable to add cross stays,
similar to those used for the wings proper, but light in proportion. The
covering is similar to the covering of the wings; they are formed with valves,

page_text: which permit the air to pass 'downwards, but not upwards. The alæ spuriæ
are worked during the rising of the wings, and should perform several strokes
during that time, and-they should also strike simultaneously with the strokes of
the wings. Small tubes, partially filled with shot or other material, which
will slip easily from one end to the other, are placed along the fore parts of
the wings in such a manner that the shot or other material within each tube
shall fall to the farthest extremity of the tube as the wing strikes downwards,
and fall back when the wing is raised, and by this means increase the force of
the stroke at the moment it is most required, in consequence of the compres
sion of the air underneath caused by the action of the wings; and small tubes
of a similar kind may even be used for the alæ spuriæ. s, Figure 2, is a stay,
which is of steel, and flat, and having a sharp edge in front; it is attached to
the fore part of the seat or hull by a spring, which permits freedom of action
to the wing; it represents the membrane, which is placed in a similar position
in' birds, and is 'formed like it, concave in front, as I consider that this form
permits the air to pass more freely under that part of the wing where the force
of the current acts with the greatest advantage; other stays, united to the seat
or hull in a similar manner, are placed behind this. When the apparatus is
intended to be used by a single person, the seat is formed, as nearly as possible,
like a small saddle, on which the person sits, as on horseback, the saddle being
made as narrow as possible, so as to permit him to walk before rising and after
descending, the machinery used for working the wings being placed in front,
or the wings may even be worked by cords merely pulled by the hands. Rests
for the feet; while flying, are so arranged that they can be raised so as not to
inconvenience the person while walking. Figure 1 represents an apparatus
adapted to this purpose; this Figure represents the under surface, as it would
be seen if "flying over head; when closed, the joints t, t, reach to about the
ancles, the parts u, u, close backwards, and the extremities of the oars forwards;
the tail may be made to close 'downwards, and when' in that position its
extremity should reach to about the same distance from the ground as the
joints t, t,; w, w, are openings which admit the thighs of the person who
occupies the seat or saddle. Figure 24 represents another modification of
wings, in which the oars are inclined backwards; the parts u, u, may be closed
backwards; the parts a, a, forwards; and the oars e, e, close backwards.
Figure 5 represents a part of the apparatus which I term the scapular sail;
its office is nearly similar to that of the upper rudder or tail in large vessels;
it affords great assistance in steering, and also in sustaining the weight. The
canes x, x, pass under the shoulders, and the lower ends are attached' by cords
to springs set in the front saddle, in such a manner that the scapular sail may

page_text: be set at any angle required, and these canes may be disunited from the saddle
when the apparatus is no longer required for use, and the scapular sail may
then be closed downwards behind the person's back, and the canes may be
formed with joints, so as to admit of the ends being closed downwards on the
breast, or they may be formed so that they can be disunited in any convenient
part. The part p is convex above and concave below, and the part q is flat, or
nearly so. Light cross stays should be used, and it should be supported by
stays from the waist or from the back part of the saddle, the upper ends being
jointed to the ribs or shafts, and the lower ends attached by cords or other
convenient means, admitting of their being freed when it is desired to close the
apparatus; these cords should be attached to springs fixed to the saddle. The
framework is covered in a manner similar to that of the tail or rudder, except
that the materials may be lighter; it may be furnished with valves, but they
are not necessary. I prefer inflating the upper part with atmospheric air.
Figure 6 represents a small parachute, the ribs of which are jointed to a collar
which is clasped round the neck. y, y, are two ribs or pieces of cane or
whalebone, which are united as one when in use, but may be disunited, in
order to admit of the parachute being placed in its position or removed at
pleasure. It is kept expanded by stays, the lower ends of which are attached
by cords or other convenient means to a belt which is fastened round the waist,
in such a manner that they can be disunited when desired, and the parachute
can then be partially closed over the shoulders; the upper part should be
inflated with atmospheric air. Figure 7 represents a parachute, in the more
strict meaning of the word; it is only intended to be used with an apparatus
suitable for a single person, and may be made so small as to admit of being
carried in the hand when not in use. The circular part is formed in a manner
nearly similar to an umbrella, except that I prefer using the light canes or
reeds that I have mentioned, to form the ribs, the strong ends being placed in
the centre, and the small points outwards; and I prefer making the stays or
stretchers rather longer in proportion than in an ordinary umbrella, for the
sake of greater strength, and also to increase the size of a vacuum chamber,
which I place in this part, the principle of which is explained under the third
claim. These stays or stretchers are of steel; they are arranged, as nearly as
possible, like those of an ordinary umbrella, so as to admit of the parachute
being closed, or as nearly so as possible, when not in use. I term the parts
2,2, the wings of the parachute, for the sake of distinction; I term the wings
which are attached to the seat or saddle, the wings proper; and I apply the
same term to the wings attached to the hull in large vessels. The wings of
the parachute are formed of canes or reeds, rather stronger than those used for

page_text: may
the circular part, especially the foremost canes of each wing, and very thin
boards may be added to increase the stiffness of this part, but they are not
necessary. The canes or reeds which form the framework of the wings of the
parachute, are jointed to the lower part of the sliding tube to which the
stretchers are jointed which support the circular part. c, c, are two canes. or
pieces of light wood, united at top, where a cylindrical sheath or tube is jointed
to them; this tube receives the lower end of the central shaft of the parachute,
in which it is moved upwards and downwards, carrying with it the winged
parachute, and this movement assists, by the compression of the air within the
concave part, to raise and support the weight of the person and apparatus.
Motion be communicated to the parachute in any convenient way, but I
prefer jointing the ends of canes or reeds, such as I have described, to the
canes which serve as ribs to the wings of the parachute, the opposite ends
being attached by cords or other convenient means to the canes which are
placed over the wing covers (that is to say, the covers of the wings proper,)
in such a manner that they can be removed when the apparatus is required to
be closed; but when they are in their places, they cause the parachute to be
moved upwards and downwards by the movement of the wings proper. I
prefer attaching the lower ends of these canes or reeds to springs, similar
to that represented in Figure 3, but without the additional spring d, and
extremely light and small. These springs should be attached to the canes of
the covers of the wings proper, and the lower ends of the canes which com-
municate motion to the wings of the parachute should be attached to their
upper parts. The apparatus may be so arranged that the movement may be
alternate, the parachute rising as the wings proper descend; but I prefer
the arrangement I have described. It is advisable to use light cross stays,
similar to those used for the wings proper and tail, in the fore parts of the
wings of the parachute; but they are not necessary in the hinder. parts.
The wings of the parachute are furnished with valves, similar to those of
the wings proper, the joints of which are attached to the canes which form
the ribs or shafts of the wings of the parachute. When the parachute is
closed, the extremities of the wings may be made to close upwards, for greater
convenience, by means of joints. Cords are attached to the lower end of the
central shaft, the opposite ends of these cords being attached to springs which
are set under the seat or saddle (they are made to pass through an aperture at
the bottom of the cylindrical sheath); the springs are drawn upwards as the
parachute is raised, and by their re-action cause it to descend with a quick
motion, and prevent the force of the strokes of the wings being materially
lessened by the latter having to draw down the parachute; elastic caoutchouc

page_text: is the most suitable material for these cords. The tube is jointed to the upper
parts of the canes or pieces c, c, where they are united in such a manner as to
admit of the parachute assuming an inclination conformable to that of the
wings pròper; and cords are attached to the wings and also to the fore and
hinder parts of the parachute, the opposite ends of which are conducted to
pulleys or keys attached to the seat or saddle, in such a manner that the
inclination of the parachute can be regulated at all times with precision; and
the arrangement is such that it can not only be inclined laterally, but also
raised or depressed in front or behind, as far as this is requisite. All the cords
in every part of the apparatus, whether it be of a small or large size, or used
with an aerostat or otherwise, the tension of which requires to be altered under
different circumstances or regulated with precision, are either attached to keys
resembling those of a musical instrument, but having screws cut on them, and
furnished with pins or with ratchet wheels, and detents to prevent them from
turning, except when moved by the hand, or pullies are used, which are
furnished with small ratchet wheels fixed on the axles outside the blocks where
detents are so placed as to engage in the teeth. It is most advisable, both in
small apparatus and in large vessels, that each set of cords should be of a
distinct color, and that the part which is either moved or stayed by these
cords should be of a corresponding color, as by this means confusion is
avoided. An air cushion may be placed on the canes or pieces c, c, against
which the person using the apparatus can rest his head and shoulders, the
arrangement being such that it can be removed at pleasure; the lower ends of
the canes or pieces c, c, are attached to the saddle by cords or other means,
admitting of their being removed when desired. The winged parachute is
covered with a material similar to that used for the wings proper, except that
may be lighter, and that used for the upper part should be lighter than that
used for the lower surface. The principle and construction of the vacuum and
medium chambers is explained under the third claim; the upper part of the
parachute is filled with atmospheric air, which may be removed as from an air
cushion when the apparatus is not required for use. In the small apparatus,
intended for the use of a single person, the wings proper are most suitably
worked by winches, a separate winch and handle being appropriated to each
wing; one of these is turned by the right hand and the other by the left, and
the cords which are used to raise the wings are wound round the axles, which
are turned by the winches. I consider that increased stability, that is to say,
a more perfect equilibrium is obtained under all circumstances by conducting
the cords from the right wing through guide pullies fixed on the left side of the
seat, and from thence to the axle which is placed on the left side,.and those
it

page_text: from the left wing to the right hand axle in a similar manner, as I consider
that by this means the side which will have the greatest tendency to fall, in
consequence of the greater elevation of the wing on the opposite side, when
one wing, is, raised higher or worked with greater force or acted on more
strongly by the wind than the other, will be drawn more strongly upwards at
the time when it will be advantageous that it should be so; this arrangement
is, however, not necessary, but I consider it the most perfect; it is equally
applicable to the wings used with an aerostat. One of the axles used for this
purpose in the small apparatus is represented in Figure 8, indicated by the
letter a; this axle carries a wheel having angular teeth, which communicates
motion by gearing to another wheel having angular teeth also, which is fixed
on the axle b. The teeth are so inclined that they engage while the wing.is
rising, but slip. while, it is performing the stroke; and in order to effect this
more perfectly, I prefer attaching the teeth by joints in such a manner that the
joints shall yield when pressed in the opposite direction from that in which
they are required to act. A spring inay also be so placed, that it shall draw the
axle towards' the axle a while the wing, is rising, the arrangement being
such that it may slip in a slight degree from it as the wing strikes downwards.
The axle 6 has a crank attached to it, at the extremity of the arm of which is
a pin, which turns freely in a socket, and to this the, cords which serve to work
the ala,spuriae are attached; the proportion of the diameters of the wheels or
of the wheel and pinion, by which motion is communicated from the axle a, to
the axle b, being such that the ale spuriæ shall perform several strokes during
the rising of the wing, and also strike simultaneously with it. The..most
convenient way of working the: oars and palms in a small apparatus of this
kind, is to attach the ends of the cords used for that purpose to a pin, turning
freely in a socket, at the outer end of the handle c, or fixed at the extremity of
the arm of a crank which is set in the end of the handle, as represented in the
Figure: I prefer the latter arrangement. I prefer forming the arm of this
crank with a joint in such a manner that. it will yield as the oars strike down-
wards, but be inflexible when the strain of the cord acts in the opposite
direction, while, the arm of the crank is describing the opposite half circle; and
I..prefer forming the arm of the crank which communicates motion to the alæ
spuriæ in a similar manner; the object of this is that the stroke: may ,be
instantaneous, ..but this peculiar, arrangement is not necessary. When the
wings are of a large size and used with an aerostat, and a separate person can
be employed to work each wing, wheels are used for the purpose, as represented
in Figures 9 and 10, the first being a side view and the second an end view;
in. the, former Figure the axle is supposed to be cut across and a part

page_text: removed, in order to show the arrangement more perfectly; the persons who
turn the wheels are placed nearly in the positions of men rowing, but rather
more horizontal. Figure 9 represents a man turning a wheel a, with a smaller
wheel b, in combination with it. The part c is formed by two boards with an
air cushion between them; his head also rests on an air cushion; a strap is
placed across his breast, which, combined with the other arrangements, prevents
him from being drawn forwards or raised from his position by the action of the
wheel, which might otherwise have a tendency to draw him in that direction.
There is a joint at c'; the periphery of the wheel a is furnished with boards
set at a suitable angle for the feet of the man turning the wheel to press
against them; the smaller wheel b, communicating with the larger one by
means of an endless band, is turned by the hands of the same person, so that
both hands and feet are employed simultaneously in the movement. I under-
stand that a position in some respects similar to this has been suggested as an
advantageous one for making use of a man's strength, but I am not aware
that it has ever been applied, at least to ærial navigation, for which I consider
it particularly suitable. I do not claim the idea, but I consider it peculiarly
adapted to this purpose. The cords which serve to raise the wings are wound
round the wheels d, d, Figure 10. A separate wheel and axle, with its corre-
sponding hand wheel and mechanism complete, as represented in Figures 9
and 10, is always appropriated to each wing; the wheels are let go the moment
the wing is raised to the required elevation, and the springs cause it to perform
the stroke by their re-action. e is a board, under which is a spring, so arranged
that it yields to a sudden pressure, and the person working is enabled to slip
his feet in an instant from the wheel by pressing this downwards; to this
board are attached cords, the opposite ends of which are fastened to detents which
engage in the teeth of ratchet wheels, which are set on the axle g, so as to
prevent the recoil taking place before the proper moment; but these cords are
attached to the detents in such a manner that when the board e is pushed
down, the points of the detents are raised and liberate the axle. I prefer making
use of two endless bands, one passing over each of the wheels f. f, one of these
wheels being placed at each side of the wheel a, as represented in Fig. 10, and
I make use of two wheels on which to wind the cords that serve to raise each
wing. These last-mentioned wheels are indicated in the Figure by the letters
d, d. Any number of persons that the vessel is capable of accommodating may
be employed to work the wings on this principle; the axle g, and also the axle of
the small wheel b, may be lengthened, and an additional number of wheels may
be fixed on them, but I prefer placing men in positions suitable to the form and
size of the vessel, each working a separate wheel with its corresponding hand.

page_text: canes.
wheel, and attaching separate systems of pullies to an additional number of
1, Figure 10, is the arm of a crank to which the cords which serve to
raise the oars and palm are attached, as already mentioned; these cords being
first collected in a small sheath or sheaths, which are formed of small pieces of
reed or other light material, and the cords are passed through guide pullies in
suitable positions. The crank is set on an axle, to which motion is commu-
nicated by means of a pinion having angular teeth, which is driven by a wheel
having angular teeth also, which is fixed on the axle g, the relative diameters
of these being such that the oars and palm shall strike downwards, either
once, twice, or a greater number of times during the rising of the wing; but
they must always strike downwards simultaneously with the stroke of the wing.
h is the arm of a crank to which the cords which serve to raise the alæ spuriæ
are attached in a similar manner to that in which those from the oars and palm
are attached to the arm of the crank 7. This crank is set on an axle to which
motion is communicated by means of a pinion having angular teeth, which is
driven by a wheel having angular teeth also, which is fixed on the axle g, but
the diameters of these bear such a proportion to each other that the ale spuriæ
performs several strokes during the rising of the wing. I prefer forming the
teeth of the wheels by which motion is communicated to the cranks and h,
in the manner which I have described, as the most perfect for the small
apparatus; and I also prefer placing springs in such a manner that they may
press or draw the axles to which the cranks are attached towards the axle g.
while the oars and palm and the alæ spuriæ are rising, but so arranged that
they may slip from it as far as possible when they are striking downwards. The
arnis of the cranks may be formed in the manner described as the most perfect
for the small apparatus, and this construction being at the same time the most
perfect, as I conceive, and also of rather a complicated nature, is even more
particularly suitable for machinery on a large scale, but this peculiar con-
struction is not necessary. The reason for giving a form slightly curved to the
arms of the cranks, as represented in the Figure, is more effectually to prevent
any risk of the cords tangling or catching, but this form is not absolutely
necessary. The cords from the oars and palms, and also those from the ala
spurice, must be attached to pius, turning freely in sockets, fixed at the extre-
mities of the arms of the cranks / and h. I prefer conducting the cords which
serve to work the wings from their bases, and also those which serve to work the
oars and palms, and those used to work the alæ spuriæ, through guide pullies,
placed in positions as low down as they conveniently can be, and from thence to
the axles or the arms of the cranks. The arrangement represented in Figures
9 and 10, and also that represented in Figure 8, is adapted to the right wing

page_text: only; but that used to work the left is exactly similar, except that the handle
in Figure 8, and the cranks in both arrangements which are used to work the
oars and palms, and those used to work the alæ spuriæ, are set at the opposite
ends of the axles for the left wing. All known means of diminishing friction
which can suitably be introduced should be used to remove all obstruction, as
far as possible, from the axles on which the wheels are fixed, round which the
cords that serve to raise the wings are wound, as these cords must unwind
themselves, and while so doing, turn the axles in the opposite direction; when
the wings are striking downwards. The most simple means is to place one
or more cylinders, which are permitted to turn freely round each axle, and I
make use of these even for the axles, of the pullies; the ratchet wheels being
fixed on the axles which carry, the wheels round which the cords are coiled,
do not interfere with this arrangement, as the, detents engage only while
the wings are rising, and it is only during the stroke that it is requisite that
all friction should be avoided as much as possible; washers or small discs,
turning freely round the axles, so as to diminish the friction against the sides
of the frame, should also be used, both for these axles and also for those of
the pullies. The wings may be made to perform half or quarter strokes, when
this is desirable, by liberating the wheels when the wings have been raised to
the elevation desired. This can be done either with one wing or both, by, the
person or persons who work them slipping their feet from the boards which
are set round the large wheels, at the same time pressing down the boards, one
of which is shown in Figure 9, and indicated by the letter e; the cords which
are attached to these boards having their opposite ends attached to the detents,
as already mentioned, which are disengaged from the teeth of the ratchet
wheels by pressing down the boards, the wheel 6 must, be let go at the same
time. It is, however, necessary that this should be so calculated and arranged
that the half and quarter, strokes may correspond with those of the oars and
palms and the alæ spuriæ, so that they may strike with the stroke of the
wing. The wings, or either of them, may be worked more slowly or more
quickly by diminishing or increasing the speed with which the wheels are
turned: An additional person should be employed to attend to the rudder or
rudders, or this office may be performed. by the person who commands the
others; but the steering is effected; principally, at least under difficult circum-
stances, and in strong gales or contrary winds, by means of the wings; and for
this reason, among others, I consider men's force much more suitable. than
any other power to work the wings, as judgment is required more or less in
almost every stroke, and it is seldom suitable to work both wings exactly alike.
x, Figure, 12, is a small propeller, intended to be used in a manner somewhat
:

page_text: similar to the oar of a gondola, but more for the purpose of propulsion than
steering, though it assists also in steering, It is formed by two thin pieces of
elastic wood, each of which is strengthened by a thin flat piece of elastic steel,
their basis. being moveable on pins, fixed at each side of the hull, in such
a manner that the extremities which pass, beyond the stern and form the pro-
peller, can be either elevated or depressed at pleasure. The propeller is set at
any angle required by means of adjusting screws or any convenient arrange-
ment, and is made to act on the air by drawing it alternately to one side and
the other, or if desired, to one side only, its elasticity causing it to spring back
when liberated. It is sometimes most suitable to draw it to one side only;
this propeller is, however, by no means necessary, and may be dispensed with
altogether. The forms of wings used for aerostats, which are intended specially
for perpendicular ascent, are represented in Figures 15 and 16, and also in
Figures 21, 22, and 23. Figures 15 and 21 shew the under surfaces as
they would be seen from below, if ascending with the aerostat combined.
Figures 16 and 22, which are vertical sections of the same, and Figure 23,
which is a side view, shew the manner in which the winged car or hull is
combined with the aerostat; the same letters as those used to indicate the
different parts of the wings of the locomotive aerostats are used to indicate
those parts of the wings of the ascensional aerostats which most nearly
resemble them; the part of each wing indicated by the letter k is concave; that
part indicated by the letter i is flat or nearly so; the parts indicated by the
letter e are to a certain extent similar to the oars, but still more nearly resemble
the parts of the tails of the locomotive aerostats indicated by the letter o. These
wings are set under springs in a manner; nearly similar to the tails of loco-
motive acrostats, which they very nearly resemble in form, and one side or the
other can be either raised or lowered so as to incline their surfaces at any angle
required, so far as is necessary for the purpose for which they are intended.
,, are small propellers, to a certain extent similar to those represented
Figure 12, and indicated by the same letter, but in aerostats of this class, they
are so arranged that they can be inclined towards a horizontal position at any
angle required, and, their bases should be set in boxes capable of being turned
in such a manner as to admit of their being so inclined, or placed quite hori-
zontally instead of vertically, and made to strike downwards when this is
desirable, and they may even be made to strike upwards, when descending.
Their extremities are. not required to be raised or lowered like those repre-
sented as adapted to, the locomotive aerostat, Figure 12; these propellers may
be dispensed with altogether, but I consider them advantageous...The different
modifications represented in the Drawings are those which I consider best

page_text: adapted to the particular purpose for which each is specially designed, but I do
not limit myself to these exact proportions, as the principles admit of almost
infinite modifications in the minor details.
Secondly, my improvements have reference to the form of the envelope con-
taining gas or air, which I term the aerostat. Figures 11, 17, and 19 represent
the lower surfaces of aerostats, of the forms that I consider best adapted to
locomotion or transit from place to place, but I do not limit myself to any
precise proportions; each is represented in combination with the hull, the wings
and rudders, or tails and other parts complete, as it would be seen from below,
if sailing or flying over head. Figure 12 is a longitudinal and vertical section
or clevation, which is similar in all these modifications, but either the fore or
after parts may be more or less elevated or depressed than in the Drawing. I
consider, however, that the inclination represented, or nearly so, is the most
generally suitable. Figures 13, 18, and 20, show the upper parts of these
acrostats. Figure 14 is another modification, in which the aerostat is less
capacious, and the wings larger in proportion than in the other modifications;
the same letters indicate similar parts in all these Figures. A is the aerostat
proper; B is the vacuum chamber; and B' is the medium chamber; the
principle of these and their construction are explained under the third claim;
D is the outer compartment; and E, E, are the wings of the aerostat; the
aerostat proper may be filled either with gas or rarefied air, but I prefer gas;
the situation of the stove or fire-place is shewn in Figures 12, 16, and 22, and
on a larger scale in Figure 25, in all of which it is indicated by the letter S;
the particulars as regards its form and arrangement are described under the
fourth claim. The outer compartment of the acrostat D is filled either with
nitrogen gas or atmospheric air. 9, 9, are the two foremost extremities, which
I term the arrow heads; they are formed in this manner in order that the
aerostat may encounter the least resistance possible from the air; over the
parts 1, 1, which are of glass strengthened and sustained by light bars of steel,
are lamps, so disposed as to throw the light downwards in order to shew as far
as possible the land or water over which the vessel is sailing or flying during the
night. j, j, Figures 11, 12, 17, and 19, are steel tubes covered with canes or
reeds, or bamboos to strengthen them; it is most advisable to place a bamboo
underneath and the lighter canes or reeds above. These tubes serve as chimneys
through which the smoke or heated air passes from the stove; the tops of these
chimnies, which are seen in Figures 13, 14, 18, and 20, and one of which is
seen in perspective in Figure 12, in all of which they are indicated by the
letter j', are furnished with a plate of perforated metal or wire gauze. e', e',
in the same Figures, are the tops of the chimneys, through which the smoke or

page_text: heated air passes from the lamps; both chimneys are tapered towards the top,
and the transverse section of the latter is oval, with the sharp edge in front.
I consider that the smoke or heated air issuing from these chimneys will
conduce to a certain extent to relieve the fore part of the aerostat from the
atmospheric pressure, a very small current of heated air being found to have a
certain effect in that respect; and these chimneys are so placed, that the smoke
or heated air issuing from them, after ascending, is driven backwards by the
atmospheric resistance when the vessel is advancing rapidly towards that part
of the aerostat which most requires to be relieved from the pressure. When
rarefied air is used, the heated air from the stove must be made to pass into the
fore part of the aerostat proper, but I prefer making use of gas, and I consider
the arrangements shewn in the Drawings to be the most perfect. The parts g, g,
which I term the arrow heads, are formed of steel frames, sufficiently strong in
the centre, but gradually lighter towards the front and sides, and covered with
thin steel plates which project beyond the frames in front and on the inner
sides; the latter are slightly concave, as I consider that this form tends to
divert the current of air from the part of the aerostat behind it, and to direct. it
towards the main air channel H. These arrow heads may be so constructed
that they can be turned towards either side, in order to facilitate the steering of
the vessel; and when so constructed, a wire or wire cord should be attached to
each side of each arrow head, the opposite end of which should be conducted
to the hull; but it is not necessary that the arrow heads should be moveable:
any material used for combustion in the lamps can be drawn up by cords and
pullies along the outside of the tubes j, j. It is most suitable that the lower
surfaces of the wings proper, and also of the aerostat, should be of as light a
color as possible; and metallic leaf, such as is sometimes used for small balloons,
may very suitably be employed for those parts whose situation is best adapted
to reflect the light from the lamps in the arrow heads, or from lamps placed
in any convenient positions in the hull of the vessel; the bottom of the hull,
and also of the pilot boat which is described under the fourth claim, may very
suitably be covered with thin plates of metal, which will in some degree act as
reflectors to lights when let down from the hull, or from the pilot boat. It is
advisable to cover that portion of the fore part of the outer envelope of the
aerostat indicated by the letter m', Figures 13, 14, 18, and 20, and those
parts of the aerostat represented in Figure 23, which are indicated by the
same letter, with very thin plates of steel or other metal. In the locomotive
nerostat, represented in Figures 13, 14, 18, and 20, these are attached to long
canes or bamboos, or to bamboos lengthened by the addition of a number of
canes or reeds, each lighter than the preceding, so as to preserve a gradually

page_text: diminishing form from the base, which is in front, to the after extremity, light
steel rods being passed through them. These canes or combination of canes
are represented in Figures 13, 14, 18, and 20, indicated by the letter n'.
o', o', are two similar canes or combination of canes, but lighter: Similar
combinations of canes are used in all parts of the aerostat, which require to be
kept stiff, or of a sharp or angular form, the strength of each being suitable to
its situation; they are sewed to the material of which the envelope is com-
posed, which is cut to the required shape; p, is a long cane or combination of
canes, which serves to give as sharp a form as is consistent with the general
formation to the upper part of the aerostat; 'none but the canes n', n³, are,
however, absolutely necessary; the foremost parts of the outer envelope may
be filled with bladders inflated with atmospheric air or nitrogen gas, which will
contribute to render these parts stiff without adding materially to the weight;
the length of the chimneys contributes to diminish the risk of fire, more
especially in aerostats in which gas is used, as the smoke or heated air is con
ducted in all such aerostats to the arrow heads. I consider it advisable to
place plates of perforated metal or wire gauze in one or more parts inside these
chimnies in addition to those which I have mentioned 'as placed at the tops,
and I consider it advisable to cover these chimneys, or parts of them, with
asbestos cloth, but this is not absolutely necessary. H, Figures 11, 12, 17,
and 19, is the main air channel, through which the air passes from stem to stern,
between the aerostat and the hull; smaller air channels are also constructed in
other parts, to lessen the atmospheric resistance, from which the air discharges
itself under the wings of the aerostat, where it acts most advantageously.
Over the entrances or mouths of two of these air channels, are projections,
indicated by the letter f, in Figures 13, 14, 18, and 20; these projections are
continued to the middle peak or prolongation F. These air channels are formed
to a certain extent like wind sails, but I prefer making the cross sections of an
oval form with the narrow part at bottom, and I make use of pieces of elastic
wood to keep the air channel in this form. The wings of the aerostat E, E, are
inflated, and may be considered as prolongations of the outer envelope, except
in as much as they are divided by the air channels u, u; they are brought to as
sharp an edge as their general form will admit at the sides where the canes t, t,
are sewed to the silk or other material of which the envelope is formed. Cords
are attached to these canes, the opposite ends of which are either attached to the
canes of the covers of the wings proper in such a manner that the latter draw
down the former when they strike downwards, or' "they may be conducted to
springs set in any convenient part of the hull of the vessel, and by this latter
arrangement, the springs of the wings proper are not taxed to draw down the

page_text: wings of the aerostat, but' even when the latter arrangement is adopted, I con-
sider it generally suitable that both the wings proper, and the wings of the
aerostat, should strike at the same time. I consider that the spring of the air,
after the stroke, increased by the force of the currents passing through the air
channels and by the sides of the acrostat, will raise the wings of the aerostat as
much as is absolutely necessary, but separate cords may be used for this purpose.
I préfér atmospheric air generally for the inflation of the wings of the aerostat,
but gas may be used in any case in which it is considered essential to obtain the
greatest degree of buoyancy possible; the cords that are used to communicate
motion to the wings of the aerostat should be made to pass through guide pullies
in suitable positions, so as to give the most advantageous direction possible to
the strokes of the wings of the aerostat, and 'conducted from thence either to the
wings proper or to the springs used for working them. When separate springs
are used for that purpose, the wings of the aerostat assist most materially in
steering the vessel, besides the advantage of counteracting any tendency that
the action of 'the wings proper alone imight have to carry forward the hull of
the vessel in advance of the aerostat above. The air channels u, u, Figures 11,
13, 14, 17, 18, 19, and 20 permit the air to pass downwards from that part
of the upper surface of the aerostat, which would otherwise assume a form to
a certain extent hollow or concave when the wing is at its full elevation; the
air which passes down through these air channels discharges itself under the
wings of the aerostat; pieces of thin flat elastic wood may be used to keep
these air channels in their proper form; these air channels are furnished with
valves or flaps, which permit the air to pass downwards but not upwards, except
when opened by pulling cords. As regards the main air channel "H;'which is
open below, except so far as the hull occupies the lower part, it is kept in the
required form, which is concave, by means of thin flat pieces of elastic wood,
which are sewed into the material; the positions of these pieces' of 'elastic wood
are indicated by the letters h, h, Figures 11, 17, and 19, and parts of them
are seen in the section, Figure 12, where they are indicated by the same
letters. Bands or flat pieces of elastic caoutchouc are placed over these pieces
of elastic wood, and cords may be conducted from their extremities' to' the hull;
these cords should first pass over guide pulleys fixed on the canes w, w, and
from thence round other guide pulleys, in any suitable positions, to the hull;
the ends of those flat pieces of elastic wood, which may be further strengthened
by the addition of pieces of thin elastic steel placed over them, are made fast to
the canes w, w, which serve to strengthen the sides of the main air channel,
and to keep this part in the required form. y, y, Figures 11, 12, 17, 'and '19,
are the stern fans; these are attached to the bamboos or canes which serve to

page_text: keep the hinder part or stern of the aerostat in the required shape; these
fans direct the air against the stern of the aerostat, and also contribute very
materially towards the propulsion of the vessel by the direction of the stroke
backwards; they are also extremely useful in steering, as either may be used
independently of the other, and they may even be so arranged as to strike
forwards instead of backwards, when required to check the speed of the vessel,
or one may be made to strike backwards and the other forwards when turning
or altering the direction of the vessel; they are attached to the canes or
bamboos z,, by means of flat pieces of elastic steel, which may be said to act
at the same time as joiuts and springs these yield, when the fan is pulled,
to either side, and spring back by their elasticity, at least so far as their
strength will permit; they are worked by cords attached to the fans, the
opposite ends being conducted to the hull of the vessel, guide pulleys being
used for all that require them. It is advisable to have cords attached at
both sides of each fan, both to assist the stroke, as their situation does not
admit of very strong springs being used, and also to give the power of
causing them to strike forwards as well as backwards, when so required.
This is very useful before descending, to check the speed. of the vessel.
These fans are formed of canes strengthened by steel rods and covered with
silk. The wheels and axles that are used for working the wings may be made
to communicate motion to these fans by the use of ordinary combinations; but
it is much more advisable, when the vessel is sufficiently large to admit of
it, to work them separately from the wings, and the same axle or axles which
give motion to these fans, may very suitably be made to communicate motion
to the small propeller a, Figure 12, the principle of both being, to a certain
extent, similar. As regards the materials of the envelopes which form the
aerostat proper and the outer covering, they may be formed in the usual way
and of the ordinary materials, but I consider it most advisable to have cords
sewed in all the seams, and the ends of these cords made fast to the hull, the
cords being prolonged sufficiently for that purpose. Canes or bamboos are
used to give stiffness to any part requiring it, in the manner I have already
described; but I consider the most perfect manner of forming the envelopes,
especially in very largo aerostats, is to place either parchment or very light
steel plates between two pieces of silk or other suitable material, and to unite
them by means of caoutchouc, in a manner similar to that in which two pieces
of cloth are united in forming air-proof fabrics. These pieces of parchment or
steel plates should be placed between the-seams, so that the parts immediately
forming the seams may permit a certain degree of expansion to the entire
envelope. When steel plates are used, the edges should be covered with a

page_text: little cotton or other soft substance, to prevent them from injuring the material,
and there should also be an additional thickness of caoutchouc round the edges,
but I consider that parchment is generally more suitable than steel plates. In
very large vessels two pieces of material formed in this manner may be united,
the seams of the one piece being placed in the intermediate part between the
seams of the other piece, in order to render the envelope still more impervious
to the gas, and to make the strength more equal throughout. When the
vessel is sufficiently large, it is very advisable to make use of two or more
separate envelopes in addition to those represented in the Figure, each envelope
containing a denser medium or heavier description of gas or air or less rarefied
than that contained in the compartment below it. The principle of this
arrangement is more fully explained under the third claim: An outer envelope
with projections in the form of wings, and also prolonged in the form of two
points or peaks, or with the addition also of a third in the front, with air
channels resembling the general form represented in the Drawings as far as
can conveniently be arranged, may be added to any ordinary balloon, and a
winged boat may be used in combination with it; but it will necessarily be much
less perfect than the more complete arrangement I have described. When the
aerostat is intended specially for perpendicular ascent, and not for transit from
place to place, I form it as represented in Figures 15 and 16, or as represented
in Figures 21, 22, and 23. Figures 15 and 21 represent the lower part as it
would be seen from below when elevated immediately over head; Figures 16
and 22 are vertical sections of the same; Figure 23 is a side view of the
latter; the side view of the aerostat, of which the lower part and section are
represented in Figures 15 and 16, is nearly similar, with the exception of
being smaller at the top and rather larger at bottom. The same letters indicate
parts similar to those indicated by these letters in the preceding Figures, or as
nearly so as the difference of form and construction will admit. A is the
aerostat proper, which is filled with hydrogen gas, or gas of the ordinary
description, but I prefer pure hydrogen; B is the vacuum chamber; and B' is
the medium chamber; and D is the outer chamber or compartment which is
filled either with ordinary gas of a greater specific gravity than that in the
aerostat proper, or with nitrogen or atmospheric air, or combinations of these,
according to the height to which it is required to ascend; E, E, are the wings
of the aerostat, oight in number, from which cords pass to the covers of the
wings proper, or to springs set in any convenient part of the car or hull, by
which motion may be communicated to them without taxing the springs of the
wings proper to work them. I, however, consider it generally most advisable
that they should strike at the same time as the wings proper immediately below

page_text: them. I do not limit niyself to this exact number, as either a greater or
smaller number. may be used; but I préfer. this number generally for aerostats
of a large size; four is, however, a very suitable number for. small aerostats.
u, u, are air channels, the object of which is to permit a'free passage down-
wards to the air from above; these air channels are furnished with valves which
permit. the air to pass downwards, but not upwards, except when opened by.
pulling a cord, which. can be done when desired. All the valves may be made
to open in a inanner similar to the valve of an ordinary.balloon..by having
cords attached.to them, the opposite ends of which should be conducted to the
hull or car. Although the aerial vessels represented in Figures 15 and 16, and
in Figures 21, 22, and 23, are specially designed for perpendicular ascent, they
can; nevertheless, be guided to a certain extent, or the force of the wind
counteracted or modified which would drive an ordinary balloon in a lateral
direction, and prevent it from ascending perpendicularly, by working the
wings on one side only when this is found. suitable, or any, number of them,
and setting the others at any suitable angle according to circumstances; or by
working some of the wings with greater force or more quickly than others, or
by causing some of the wings to perform only half or quarter strokes, and
working the others with their. full force. The aerostat represented in Figure 16
is smaller at the top than at, the lower part; the object of forming it in. this
manner is to endeavour to diminish the atmospheric resistance from above," and
also to throw off the rain in wet weather better than the ordinary, form; but I
consider that these objects, or at least. the first and principal one, is more fully
attained by the form represented. in Figures 21, 22, and 23. An outer
envelope and wings may easily be added to an ordinary balloon, and an air-
channel may be made to pass through it, and the winged car or hull may be
adapted to it, but it will be much less perfect than the more complete combina
tion described.... Gold-beaters'. skin may be substituted for parchment or steel
plates in forming all parts of the envelopes which are not exposed to a very
strong pressurė
T
Thirdly, my improvements have reference to the formation of vacuum
chambers or parts of the aerostat; and also of the wings proper, and parachutes,
and other parts of the apparatus, from which the air, is either partially excluded;
or exhausted to the; extent generally understood when the term vacuum is
used, or nearly so according to circumstances: The large vacuum chamber B;
Figures 12, 16, and 22; has inot only the advantage of serving as a vacuum
for the purpose of rendering the atmospheric. pressure: more efficacious in
elevating and propelling the vessel; but serves also:.to admit the gas from the
aerostat proper when too much expanded by, heat for, great elevation, and by

page_text: this means the, loss of gas is prevented, as it can be again returned to the
aerostat proper when desirable ;; and this chamber or compartment also serves
when-not occupied by the gas to admit the atmospheric air when it is desired
to descend; these two uses do not interfere with each other as they are required
at different times. In the interior, of the vacuum chamber is a bag or envelope
of silk or other suitable material which is covered by a net, and, drawn, by
cords passing through the meshes towards the aperture a, when it is desired
either to return the gas to the aerostat proper, or to expel the atmospheric air.
Rings may also be sewed to the seams of the bag through which the cords may
be made.to pass. When the gas is to be expelled, the valve b is opened; when
the atmospheric air is to be expelled, the valve c is opened. The gas..is
admitted when so required through the. valve b, either by the pressure of the
gas, a' spring being so arranged that it shall yield when the pressure acts with
a. certain force, or it may be furnished with a cord by pulling which the valve
is opened in a manner similar to that of an, ordinary balloon, or both the
spring and cord may be used for greater security. When it is desired to admit
the atmospheric air, the valve c. is opened. A cord should be attached to the
upper extremity of the bag to draw it upwards, when it is, desired, to admit
either the gas or atmospheric air, and this cord should pass down at the stern
of the aerostat in the form represented in Figure 12, and through the air
channel H, in the forms represented in Figures, 16 and 22; to the hull. I
form the lower and hinder surfaces of the vacuuni chamber of silk or other
similar material, doubled, with parchment or steel plates between, and united
in the manner. I have already described, and I place inside this a close.net
work, which may be of ordinary material, but I prefer elastic india-rubber
cords; within the net work I place cords which should be drawn tightly.to any
convenient parts which are strong enough to bear the strain. I prefer that these
cords should be of elastic caoutchouc. In the: stern of. the locomotive aerostat
I draw these cords across, attaching the extremities to the canes or bamboos
or combinations.of.canes z, .. These canes or,combinations of canes are seen
in Figures 11, 17, and 19, in which the stern of the aerostat is seen in per-
spective, and in this view it is necessarily fore-shortened; a part of one
these canes or combinations of, canes or of bamboos and canes is seen in
Figure 12. It is most suitable to attach one extremity of each cord to the
lighter part of one of these, and to attach the opposite end to the stronger
part of the opposite one, or at least to attach one end of eacli cord rather
higher than the opposite end which is attached to the opposite cane or combi-
nation; by this disposition the cords cross each other obliquely: The light canes
or combinations. bear the strain better by this arrangement, and from every
EO

page_text: point in which either extremity of any of these cords is attached to either
cane or combination of canes, or of bamboos and canes, a stay proceeds to the
hull, which sustains the cane or combination, by drawing it at the same time
towards the opposite direction or as nearly so as possible; these canos or com-
binations are lengthened in a manner similar to that already describee. By the
arrangement I have described the net work sustains the envelope, and the
cords sustain the net work when the pressure of the external air, compressed
and agitated by the actions of the fans y, y, as well as by the force with which
it rushes through the air channels as the vessel is urged forwards, acts against
the hinder surface of the vacuum chamber. Pieces of elastic wood, similar to
those used for the main air channel, are also used for this part of the aerostat,
with this difference, that the pieces of elastic wood which are placed within
the envelope, and on the inner side of the net work and sustaining cords, are
bent like bows by their strings and are in this case curved outwards. This
gives a convex form to the stern, and it is most suitable to conduct the cords
which communicate motion to the wings of the aerostat through guide pulleys
set as near as conveniently may be to the centres of these bows, in such a
manner that the tension or drawing of these cords may have a certain effect
in drawing these bows outwards, and so assist in preventing them from
being forced inwards by the pressure of the air without; and this position will
be also very suitable to give, a proper direction to the strokes of the wings of
the aerostat. Some of the cords which serve to work the stern fans may also
be drawn through guide pulleys fixed on these bows. The cords by which the
pulleys are attached to the bows must be passed through the envelope, and
the apertures afterwards perfectly closed and rendered air-tight. Cords may
also be attached to these bows, the opposite ends of which may be attached to
the hull which will contribute to draw these bows outwards, (more especially
if the cords are conducted to guide pulleys fixed on the upper cane of the
upper tail cover and from thence to the hull,) and the weight of the hull is by
this means made to contribute towards the distension of the vacuum chamber.
When the force of the atmospheric pressure acts against it, the positions of
these pulleys must be so arranged as to regulate the tension, so that it will not
be too great on any particular point, or in a direction likely to injure the
elasticity of the bows. The lower surface of the vacuum chamber which is
subjected to a similar pressure is sustained by the bows h, h, as the lower part
of the vacuum chamber is immédiately over the main air channel, and extends
over a considerable part of it. That part, however, which forms or corresponds
with the lower surface of the vacuum chamber is sustained by a net work and
sustaining cords inside, similar to that already described in aerostats of the

page_text: forms represented in Figures 16 and 22. The lower surface of the vacuum
chamber is most conveniently sustained by means of a number of hoops of
elastic wood placed within a net work and sustaining cords, and these hoops
may also be made to contribute to the support of the upper part of the
chamber. Cords, indicated by the letters u, v, Figures 16 and 22, may be
conducted from these hoops to the hull; these cords may be of ordinary
material, but I prefer elastic caoutchouc; the dotted lines represent the posi-
tions of these hoops. The hoops h, h, are sewed to the material of which
that part of the vacuum chamber is composed, which is next the main air
channel H. They serve to support the hoops within, being joined to them at
the parts where they touch them. The upper part or roof of the vacuum
chamber is formed of a very light trellis work of slit canes or reeds, to which
bladders or small bags of silk or other light material, so prepared and
varnished as to be impervious to gas or air, are attached, one of these being
attached to the trellis work at each point where the canes or reeds cross each
other, and being of such a size and proportion that when inflated the sides of all
the bladders or small bags touch and slightly press against each other, as is
seen in the longitudinal section of the aerial vessel, Figure 12, with this chamber
or compartment in its proper position indicated by the letter B, and in Figures
16 and 22, where it is indicated by the same letter, and a portion is shewn on a
larger scale in Fig. 28. A small quantity of air or gas is introduced into these
bladders or small bags, so that they become fully inflated when the greatest
degree of exhaustion or rarefaction takes place in the vacuum chamber.
Smaller bladders or bags are placed over these in order to render the upper
surface as nearly even as possible, these latter having also a small quantity of
air or gas within, so as to become inflated at the same time as the first; any
soft light substance, such as down, may be placed above to fill the remaining
intervals, but this is not necessary. The trellis work and bladders or small
bags are covered by an envelope of silk or other suitable material, doubled
with stiff paper or other light material between and united in a manner similar
to that already described, but a much lighter material is suitable for the
covering of the upper part than for that against which the currents of com-
pressed air are made to act. The upper part of the vacuum chamber in the
form represented in Figure 12 is as sharp as is consistent with the general
principles and arrangement, that is to say, similar to the front of a cuirass or
what is commonly termed a pigeon-breast, or it may be sharper. One or more
canes or combination of canes such as have been already described, are used
to sustain the upper part of the trellis work. The difference of weight between
so small a quantity of gas or air as is required to be introduced into the

page_text: bladders or small bags is so trifling, that I prefer, generally; to make use of
atmospheric air for this purpose, especially in locomotive vessels. The roof of
the medium chamber B is formed in the same manner as the roof of the
vacuum chamber, but a larger quantity of air or gas 'must be introduced into
the bladders cr
"or bags, as the gas or rarefied air in this chamber or compartment
is never exhausted to the same degree as in the vacuum chamber, the use of
this chamber being to lessen the downward pressure of the gas or air in the
aerostat proper above. In large vessels, any number of inedium chambers
may be used that may be found suitable, each containing a denser medium in
proportion as it is higher or further i
all containing rarer niediumns the removed from the vacuuin chamber, but
1
aerostat proper: If rarefied air be used
instead of gas; the same relative proportions as regards the density or-rare-
faction of the air in the different chambers or compartments inust be observed.
Tubes should pass from each of these chambers and also from the aerostat
proper to the hull of the vessel, and a separate gauge should indicate the
degree of density or rarefaction in each, in order that this may be known at
all times with precision. I consider that by proper precautions being taken in
this way, joined to the use of the stove or fire place and chimney which are
described under the fourth claim, that even gas rarefied by heat may be used
when it is required to ascend to a great height. But in this case nitrogen gas
should be used for the outer envelope, and a sufficient quantity of nitrogen
should be kept in any convenient place, so that a jet may be made to act
against any part in case of accident, and these precautions will be advisable in
all vessels, although not equally necessary. The vessel should be furnished
with exhausting springs or with contrivances formed to a certain extent like
bellow's; I prefer the latter, which I form very nearly like ordinary bellows';
a pipe from the bag which is placed within the vacuum chamber admitting the
air from thence into the bellows, and it is discharged when so required 'under
the vessel through the nozzle, and by this means the bag can be more perfectly
emptied. Springs or bellows may also be used in a similar manner to draw off
any gas which might otherwise remain' in the bag when gas has been
admitted and afterwards returned to the aerostat proper, as far as this can be
done by the mean's already described; but for this purpose a separate bellows
or syringe must be used, and the gas"must pass through the nozzle of the
bellows or from the syringe into a 'pipe communicating with the aerostat
proper. Either bellows or syringes niay also be used to force atmospheric air
into the bag, and so increase the density and consequently the weight when it
is desired to descend. "When syringes are used I form them of pieces of
bamboo or light wood with very thin metal 'lining, and they may be strength-

page_text: gas
ened by light steel hoops on the outside; I work the pistons by means of
screws, or racks and pinions. I find it most convenient generally to place them
in positions' nearly horizontal. It is not my intention that the exhaustion
should be kept up constantly to an extreme degree in the vacuum chambers;
they are principally intended as a means of giving the vessel an impulse
upwards or forwards when more than ordinary force is required, or at any par-
ticular moment, and to give a more perfect command of the movement of the
vessel by the possession of: such a power, capable of being applied at any
moment or modified at pleasure;but under ordinary circumstances, after the
vessel has attained a sufficient heiglit, it is advisable to lessen- the strain on
the materials as much as possible. The same relative proportion between the
density or rarefaction of the or air in the vacuum and medium chambers
should be kept up, as far as possible under all circumstances, except when
descending, when this is not important. Bags similar to those placed within
the vacuum chambers may be placed within the medium chambers and made
nise of in a similar manner, or the rarefaction of the gas or air in the latter may
berregulated by means of the bellows of syringes alone: I consider it advan
tageous to make use of vacuum chambers with 'medium chambers above them
on a similar principle for the wings proper and tail, and also for the large and
small parachutes, but they are not necessary; they may even be used for the
scapular sail; they may, however, be dispensed with altogether, both the aerostat
and wings and all other parts of the apparatus being capable of being used
without these, vacuum and medium, chambers, but I consider that' they will'
add very considerably to their efficiency. The section of the wing, Figure 4,
and the sections, Figure 16 and Figure 22, shew the position of the vacuum and
medium chambers' which I consider most advantageous, but I do not confine
myself to these precise forms or arrangements; they are indicated by the same
letters as the larger chambers; their positions in the tails are shewn in
Figure 12. When used for the scapular sail they are placed in similar
positions to those in which they are placed in the tails. In the parachutes the.
vacuum chambers occupy the part immediately aliove the stretchers which
serve to support the lower surface of the vacuum chamber, the material being
strengthened by the addition of parchment or other strong material, and also
supported by a net work and cords within In the small apparatus the vacuum
and medium chambers of the wings inay be formed in a manner somewhat
similar to those of the parachute so that they will open or become 'dis-
tended when the wings are opened, and close when the wings are closed.
Screws or other mechanical means may be used to assist in opening them,
as there will be a certain resistance from the atmospheric pressure without

page_text: if no air is admitted; or the air may be permitted partially to enter and be
afterwards exhausted by means of air syringes. or. bellows, which latter are
more conveniently adapted to the apparatus than syringes. I prefer making
use of two small bellows, one at each side of the front of the saddle; either
these or air syringes should always compose a part of the apparatus. But I
consider the most simple and efficacious means of emptying the vacuum
chambers, is by means of bags placed within them, which are drawn by cords
passing through the meshes of nets towards apertures furnished with valves, in
a manner similar to that already described as adapted to vacuum chambers of
aerostats. The upper parts of the vacuum and medium chambers. of the
parachutes are sustained by the canes or other material which form the frames.
I make use of two frames, one placed over the other, as shewn by the dotted
lines in Figure 7, the lower one forming with its covering the roof of the
vacuum chamber, and the upper one forming the roof of the medium chamber;
the vacuum and medium chambers in the small wings may be sustained by
any light frame work with a net. and sustaining cords.. The stays which pass
from the canes of the wing covers to the bases of the shafts, and those which
pass to the stems of the wings pass through the medium and vacuum chambers
and contribute to their support, being fastened to the roofs of each as they
pass through, and afterwards conducted to the shaft or stem. I consider it
advantageous to place a funnel or tube terminating above with a valve opening
inwards, and with a bell mouth or trumpet mouth below, passing through the
vacuum and medium chambers and the upper chamber containing atmospheric
air in the large parachute; the aperture at top may also be of a similar form.
The valve permits the air to pass downwards whenever the pressure is greater
above than below, but does not permit it to escape upwards except when
opened by pulling a cord, which can be done when descending or at any time
it may be desired. The reason for forming the extremities of the tube or funnel
with bell mouths or trumpet mouths is to permit the air to pass into it with
greater facility. I consider it advantageous to place similar funnels passing
through the vacuum and medium chambers and upper parts of the wings with
valves similarly constructed, and they may even be used in the tail and.
scapular sail or in any part of the apparatus found suitable, but they are not
necessary; one of these tubes or passages is shewn in the section of the wing,.
Figure 4, and they are seen in the sections of the wings, Figure 16 and
Figure 22, in all of which they are indicated by the letter d'. I make use of
vacuum chambers for the pilot boat which is described under the fourth claim,
and represented in Figure 25; one of these, B, is used to facilitate the descent,
the atmospheric pressure acting downwards when it is desired to descend; but

page_text: the pressure can be made to act upwards while sailing or flying by exhausting
the air from the lower chamber B', and filling the upper chamber with rarefied
air heated by the stove. The upper chamber B is formed of silk or other
suitable material, doubled, with. parchment or other strong material placed
between, and united in the manner already described; and hoops are sewed in
the material in such a manner that they serve to keep it distended, as shewn
in Figure 25, when the pilot boat is suspended or let down from the vessel,
and the strain made to act on the cords v, v. These cords are attached to the
hoops w, w, and pass from thence to pulleys or to barrels set on axles fixed in
the hull of the vessel, from which they again pass down to windlasses which are
placed in the pilot boat, and by this means the vacuum chamber is distended
while the pilot. boat is descending, or so long as it is desirable that it should
be so. If it is at any time desirable that it should be allowed to collapse while
the pilot boat is suspended from the vessel, this is effected by slackening the
cords v, v, and making the cords x, x, sustain the weight of the pilot boat.
When the pilot boat is descending, the lower chamber B¹ may be filled with
rarefied air from the stove..
Fourthly, my improvements have reference to the general form and arrange-
ments of the hull and the parts immediately connected with it, but more
particularly to the pilot boat, the vacuum chamber of which has been already
described. I give it this name as its use is to enable one or more persons to
descend before the vessel and to bring it down safely; Figure 25 is a vertical
section of the pilot boat, the lower part is seen in Figures 11, 15, 17, 19, and 21;
it is the same in all forms of aerial vessels which are used in combination with
aerostats, with the exception only of a difference in the forms of the chimneys.
The part y is of a cylindrical form, and is occupied by the person or persons who
descend in the pilot boat, whose office is to throw out grapnels and attach the
pilot boat firmly to the ground, and then draw down the vessel by means of the
cords which are wound round windlasses which are placed in the pilot boat, as
already mentioned. The pilot boat is of the most solid construction possible, and
as much as possible of the disposable weight, such as spare cordage, provisions,
&c., should be placed in it, and as many persons as can conveniently do so
should descend in it in order to effect the landing. It should be furnished with
four windlasses, two for the cords v; v, which are attached to the hoops of the
vacuum chamber, and two for the cords a, a, which serve to sustain the weight
of the boat independently of the vacuum chamber when required. The object
of appropriating two windlasses to each with separate cords is to balance the
pilot boat more perfectly while descending, and also to draw down the vessel
more effectually and with greater facility, as it is sometimes advantageous

page_text: during a strong gále of wind to draw down the vessel principally by the cords
on the windward side. The pilot boat can also be lowered to any extent
required at any time while the vessel is sailing or flying, if found necessary or
expedient, in order to steady the vessel, and the weight can be suspended by
the cords on the windward side; or the strain thrown on these cords to any.extent
that
may be suitable, according to circumstances. Its progress downwards can
be arrested at any moment, or it can be drawn up again to the vessel whenever
it is desirable to do so by means of the windlasses, the axles of which must be
furnished with ratchet wheels and detents, so disposed that the points of the
detents can be engaged or disengaged, as may be required. The part y, which
may be set upon
prows
is occupied by the persons who descend in the pilot: boat;
springs, by which means the shock is lessened when it touches the ground,
although this may be effected to a considerable extent by means of the wind-
lasses and suspending cords, as by means of these the descent can be checked
at any moment: Springs must be used only to connect the part y with the outer
portion, as the latter must rest on the ground in the most solid manner possible;
and for this reason I form the lower part in a manner having a certain resem-
blance to two sledges-crossing each other; but pointed at the 'extremities. A
section of one of these is seen in Figure 25; the bottom of the pilot boat
is seen in Figures 11, 15, 17, 19, and 21. I consider this form "the most
advantageous in order to rest in a solid manner on uneven ground, as 'this is a
contingency for which provision should be made, and the four peaks or
,,(of which two are seen in Figure 25,) projecting in different directions,
two at least of these will always have a tendency to check the progress of the
pilot boat; except when two of the rollers indicated by the letter d, Figures 11,
15, 17, 19, and 21, are let down; the use of these rollers being that either pair,
(that is to say, the two that will run in the same direction, one following the
other,) can be lowered so as to roll-along the ground. When it is desired to
draw the vessel forward they are attached by joints to the sides of the sledges,
and when lowered they keep the bottoms of the sledges from. touching the
ground. I prefer forming these rollers of wood; each of them may be divided
into two by removing the middle part, leaving the middle part of the axle
uncovered, in which case the arrangement will 'more nearly resemble the wheels
and axle of an ordinary carriage. This latter modification is shewn in Figure
19. Anchors or grapnels are attached to the peaks or prows 2,2, as represented
in Figure 25. I prefer setting these under springs, in some degree similar to
those used for the wings, but they are so arranged that they cause as little
upward spring as possible to the pilot boat, when the anchors or grapnels are
made to strike downwards; their use is to: cause the flukes of the anchors to.

page_text: strike and enter the ground more effectually; these springs are, however, not
necessary. The persons descending in the pilot boat must also be provided
with grapnels,.which may be of the ordinary description, but I prefer forming
one or more of them with the flukes attached to the shank by joints, and
pressed inwards. towards: the shank by springs, in such a manner that the
flukes shall strike inwards. towards the shank. when. liberated, in a manner
bearing a certain resemblance to the action of the talons of a bird, separate
cords being attached to each of the flukes, and all these cords being collected
in a small sheath, and so arranged that the flukes can be raised or drawn out-
wards or permitted to spring downwards or inwards by fixing these cords in any
convenient way when the flukes are not required to act, and letting them go
when it is desired that they shall enter the ground or seize any object.. An
additional advantage derived from the, use of the pilot boat and from arranging
it in such a manner that it can be lowered at any moment from the vessel is,
that the stove or fire-place, which I consider useful under all circumstances, but
which is indispensable if rarefied air or gas rarefied by heat is used, being placed
in the inner compartment y of the pilot boat; either this part or the entire pilot
boat can be lowered at once in the event of danger from fire, or even sacrificed
in án extreme case. The most perfect arrangement is to unite the inner com-
partmenty to the outer, in such a manner that they can be disunited when so
required, and also to have the stove so constructed and placed that it can be
let down independently: The stove is indicated by the letters, Figure 25,
and its situation is indicated by the saine letter in Figure 12, and in Figures
16 and 22 The upper end of the lowest portion of the chimney which is
attached to the stove fits either into or over the lower extremity of that part
which is made fast to- the hull, but it can be slipped from it when the pilot
boat is lowered." When the gas or air in the aerostat is not required to be
heated, the stove and chimneys are not absolutely necessary, but I consider
them desirable. When the pilot boat is lowered, the air may be permitted
to, pass, upwards through the stove and the portion of the chimney which
remains attached to it, by forming the bottom of the stove in such a manner
that it can be removed or made to slide to one side; and I prefer forming it in
this manner. Air passages may also be formed both through the inner and
outer portions of the pilot boat; which will permit the air to pass freely from
the bottom upwards as the pilot boat is descending or at any time it is
desirable, but which can be closed at'pleasure. The arrangement represented
in Figures 16 and 22 is adapted to heating the gas, and I consider this the
most suitable for aerostats of this class. When the gas in the aerostat is, not
required to be heated; the valves at the entrances of, the pipes p', p', must be

page_text: closed, and the heated air will then ascend directly through the tops of the pipes
or chimneys t, t. Valves must also be placed within the pipes or chimneys at
-the points q', q', to prevent the heated air escaping when it is desired to heat the
gas in the aerostat, except so much of it as may be necessary to avoid danger,
which
passes out of the chimneys t, t. These valves should open upwards,
and be so constructed that they will yield to a certain pressure. There may be
any convenient number of the pipes indicated by the letters p', p', in Figure
22. Either the pipes which terminate in the chimneys t, or those which termi-
nate in the chimneys t², may be used, or both of them. If rarefied air is used,
the heated air must be allowed to enter the aerostat, and in this case the
pipes p', p', must be so formed as to open into the aerostat, but I consider the
arrangement represented as the most suitable, gas being much more suitable
than rarefied air for this class of aerostats. n, Figure 25, is an outer tube
which is filled with nitrogen gas. Any part, or the entire of the upper
portion of the chimney, may be protected in a similar manner. I consider it
advisable to cover the stove and either the entire of the chimneys, or those parts
most exposed to risk from fire, with asbestos cloth, but this is not absolutely
necessary. If it is not required to heat either the gas or air in the aerostat, all
these tubes and chimneys may be dispensed with. L, L, Figure 12, is a
longitudinal section of the upper part or covering of the hull, which may
be formed of light boards or any light material. I prefer this form, as I con-
sider it best adapted to diminish the atmospheric resistance in front. One or
more elastic tubes, partially filled with shot or with any material which can be
made to slip easily from one extremity of the tube to the other, or a number of
short cylindrical cases containing provisions or any articles which can conve-
niently be packed in them, the cases being so fitted that they will slide with
facility within the tube, are placed in the hull of the vessel in such a manner
that either of the extremities of the tubes, or both of them, can be made to
pass beyond either side of the hull, and so assist in righting the vessel or main-
taining its equilibrium when acted on strongly by the wind or by the currents
of air produced by the action of the wings or any other cause; and these tubes
may also be made to serve to raise or lower the head when so required by the
adjustment of the weight. I prefer placing one of these tubes in front of the
pilot boat, and another behind, each tube being attached in the middle to
the hull in such a manner that the extremities of the tubes can be moved in
any direction required with the greatest facility at any moment. Apertures
'are formed in as many parts of the hull as convenient, through which lamps
or lights of any convenient kind may be let down during the night, in order
more clearly to shew the nature of the land. or water over which the vessel may

page_text: be passing; but the lamps placed in the arrow heads of the aerostat above
should, generally speaking, be sufficient for this purpose.
Out-
Fifthly, my improvements consist in the construction of a landing place for
aerial ships with a railway conducting from thence to a building capable of
receiving them. These are by no means necessary for the purpose of effecting
a safe landing, which I consider may be done by means of the improvements
already specified in any tolerably open country; but I consider that a building
capable of containing the aerostat with its apparatus complete, and having
folding or sliding doors at one side of the building sufficiently large to admit
of the aerial vessel entering and departing, will be necessary for the full
efficiency of my system in a practical point of view, and when it is required to
conduct the aerial vessel into the building, a railway will become necessary for
this purpose. The most advantageous position for the landing place is either
a plain in a level country, or an elevated position in a hilly one, when such can
be obtained free from trees, buildings, or other obstructions. A circular space
should be levelled, or partially so, as far as practicable, according to the situ-
ation, and it should be surrounded by a paling or railing, both the uprights
and cross-bars being perfectly round and smooth, and it is advantageous
that they should be painted white in order to be more conspicuous.
side these I place lights, which may be of any convenient kind. They are
placed all round the outside of the paling or railing, and covered above
with glass, and furnished with reflectors so arranged that the light may be
as conspicuous as possible to aeronauts sailing above. The top of the glass
roof or covering should not be quite so high as the top of the paling; a second
paling or inclosure may be constructed round the lights. The railway or guide
rails are set in the inside of a hollow trunk, and there are three lines of guide
rails within the trunk, one at bottom and two at top, one being at each side
of the longitudinal opening. The principal object of the trunk or tunnel is to
prevent the vessel being drawn upwards by the aerostat or impelled sideways
by the action of the wind against it. I prefer having two of these trunks or
tunnels in order to effect this object more perfectly. Each of these is furnished
with a rope, the object of which is to keep down the vessel and steady it, and
to afford a simple means of drawing it forwards, a portion of each of these
ropes being wound 'round windlasses which are turned by the hands of the
aerial navigators, and one end of each rope being made fast inside the building
and the other at the landing place, the vessel is drawn forwards by turning
the windlasses. Each hollow trunk is formed with a longitudinal chase or
aperture, through which three tongues, which may, however, be united in one,
depend vertically from the railway car, on which the hull of the vessel is placed.

page_text: A. machine. which may be termed a travelling guide, which is made to fit in
the interior of the tube runs on castors. which turn within the guide rails,. or
it. may be furnished with an additional number of castors which may run
both within and at each side of the guide rails; I prefer the latter arrange-
ment. Other-castors.run in, a similar manner within, or both within and at
each side of the guide rails above. The latter are set at each side of the
longitudinal opening, which is as narrow as is consistent with allowing sufficient
substance. or thickness to the tongues' or tongue.; The ropes pass under
wheels whose axles are fixed on the upper parts of the foremost and hindmost
tongue, or on the foremost and hindmost parts of the long tongue if formed
in one. The object of this arrangement is more effectually to keep down and
steady the vessel. The railway car is furnished with wheels which
run outside.
the tubes or tunnels. The car should be as low as it can conveniently be
made, and the hinder, part should be. formed in such a manner that the hull
of the vessel can be made to slide. upwards on it with facility. Figure.26.
represents the aerial vessel conducted along the railway and entering the
building. A is the aerial vessel. a, a, are the tunnels or trunks. B is the
building, the folding doors being open to receive the vessel; the doors may be
made to.slide if found more convenient. 6 is the railway car; the hinder part
c is formed with. a hinge, so that the hinder extremity can be allowed to touch
the ground so as to form an inclined plane, along which the hull of the vessel
can be drawn up. to its place on the car. d, d, are the ropes by means of
which the car is drawn along. e,. e, are the wheels under which the ropes are
made to pass; these wheels are not absolutely necessary, but I consider them
useful. Figure 27 is a longitudinal section of a portion of the trunk or
tunnel, shewing the interior arrangement. 'a is the travelling guide; b, b, b,
are the tongues';-c, c, are the castors; and d, d; are the guide rails..
And having now described the nature of my said Invention, and in what
manner the same is to be performed; I declare that what I claim is,
First, the construction of wings with a. horizontal tail or. rudder, the stems
or bases of which are set under springs, and which act on the air by the recoil
or re-action of these springs, this principle being more particularly applied to
the wings, but the tail being capable of being worked in a similar manner
when suitable, and the construction and use of the oars, and of the alæ spuriæ
all being, raised more slowly than they strike downwards, and the different
applications and modifications of these and other parts of the apparatus, as
described.
".
Second, the different forms and modifications of the aerostat, as described. A
Third, the construction of vacuum chambers in such a manner that they

page_text: shall be acted on by currents of air on their lower and hinder surfaces, or on
any parts which it is suitable should be so acted on, and at the same time be
relieved as far as possible from the direct atmospheric pressure on their upper
and foremost parts, or any other parts that it is expedient should be so relieved,
and the applications and contrivances for effecting the same, and the different
modifications of the principle as explained.
Fourth, the improvements in the form of the hull of the vessel and the parts
and apparatus immediately connected with it, and especially the form, con-
struction, and use of the pilot boat as set forth.
And, fifth, the plan and construction of a landing place, with lights, and a
railway, as set forth.
In witness whereof, I, the said Benjamin O'Neale Stratford, Earl of
Aldborough, have hereunto set my hand and seal, this Twenty-fourth
day of July, One thousand eight hundred and fifty-four.
ALDBOROUGH. (L.B.)