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in the MS。 received； has been made for the purpose of throwing the
hurried account of our agent； Mr。 Forsyth； into a connected and
intelligible form。
〃THE BALLOON。
〃Two very decided failures； of late … those of Mr。 Henson and Sir
George Cayley … had much weakened the public interest in the subject
of aerial navigation。 Mr。 Henson's scheme （which at first was
considered very feasible even by men of science；） was founded upon
the principle of an inclined plane； started from an eminence by an
extrinsic force； applied and continued by the revolution of impinging
vanes； in form and number resembling the vanes of a windmill。 But；
in all the experiments made with models at the Adelaide Gallery； it
was found that the operation of these fans not only did not propel
the machine； but actually impeded its flight。 The only propelling
force it ever exhibited； was the mere _impetus_ acquired from the
descent of the inclined plane ； and this _impetus_ carried the
machine farther when the vanes were at rest； than when they were in
motion … a fact which sufficiently demonstrates their inutility ；
and in the absence of the propelling； which was also the _sustaining_
power； the whole fabric would necessarily descend。 This
consideration led Sir George Cayley to think only of adapting a
propeller to some machine having of itself an independent power of
support … in a word； to a balloon ； the idea； however； being novel；
or original； with Sir George； only so far as regards the mode of its
application to practice。 He exhibited a model of his invention at
the Polytechnic Institution。 The propelling principle； or power； was
here； also； applied to interrupted surfaces； or vanes； put in
revolution。 These vanes were four in number； but were found entirely
ineffectual in moving the balloon； or in aiding its ascending power。
The whole project was thus a complete failure。
〃It was at this juncture that Mr。 Monck Mason （whose voyage from
Dover to Weilburg in the balloon； 〃Nassau；〃 occasioned so much
excitement in 1837；） conceived the idea of employing the principle of
the Archimedean screw for the purpose of propulsion through the air …
rightly attributing the failure of Mr。 Henson's scheme； and of Sir
George Cayley's； to the interruption of surface in the independent
vanes。 He made the first public experiment at Willis's Rooms； but
afterward removed his model to the Adelaide Gallery。
〃Like Sir George Cayley's balloon； his own was an ellipsoid。 Its
length was thirteen feet six inches … height； six feet eight inches。
It contained about three hundred and twenty cubic feet of gas； which；
if pure hydrogen； would support twenty…one pounds upon its first
inflation； before the gas has time to deteriorate or escape。 The
weight of the whole machine and apparatus was seventeen pounds …
leaving about four pounds to spare。 Beneath the centre of the
balloon； was a frame of light wood； about nine feet long； and rigged
on to the balloon itself with a network in the customary manner。
From this framework was suspended a wicker basket or car。
〃The screw consists of an axis of hollow brass tube； eighteen
inches in length； through which； upon a semi…spiral inclined at
fifteen degrees； pass a series of steel wire radii； two feet long；
and thus projecting a foot on either side。 These radii are connected
at the outer extremities by two bands of flattened wire … the whole
in this manner forming the framework of the screw； which is completed
by a covering of oiled silk cut into gores； and tightened so as to
present a tolerably uniform surface。 At each end of its axis this
screw is supported by pillars of hollow brass tube descending from
the hoop。 In the lower ends of these tubes are holes in which the
pivots of the axis revolve。 From the end of the axis which is next
the car； proceeds a shaft of steel； connecting the screw with the
pinion of a piece of spring machinery fixed in the car。 By the
operation of this spring； the screw is made to revolve with great
rapidity； communicating a progressive motion to the whole。 By means
of the rudder； the machine was readily turned in any direction。 The
spring was of great power； compared with its dimensions； being
capable of raising forty…five pounds upon a barrel of four inches
diameter； after the first turn； and gradually increasing as it was
wound up。 It weighed； altogether； eight pounds six ounces。 The
rudder was a light frame of cane covered with silk； shaped somewhat
like a battledoor； and was about three feet long； and at the widest；
one foot。 Its weight was about two ounces。 It could be turned
_flat_； and directed upwards or downwards； as well as to the right or
left ； and thus enabled the 鎟onaut to transfer the resistance of
the air which in an inclined position it must generate in its
passage； to any side upon which he might desire to act ； thus
determining the balloon in the opposite direction。
〃This model （which； through want of time； we have necessarily
described in an imperfect manner；） was put in action at the Adelaide
Gallery； where it accomplished a velocity of five miles per hour；
although； strange to say； it excited very little interest in
comparison with the previous complex machine of Mr。 Henson … so
resolute is the world to despise anything which carries with it an
air of simplicity。 To accomplish the great desideratum of 鎟ial
navigation； it was very generally supposed that some exceedingly
complicated application must be made of some unusually profound
principle in dynamics。
〃So well satisfied； however； was Mr。 Mason of the ultimate
success of his invention； that he determined to construct
immediately； if possible； a balloon of sufficient capacity to test
the question by a voyage of some extent … the original design being
to cross the British Channel； as before； in the Nassau balloon。 To
carry out his views； he solicited and obtained the patronage of Sir
Everard Bringhurst and Mr。 Osborne； two gentlemen well known for
scientific acquirement； and especially for the interest they have
exhibited in the progress of 鎟ostation。 The project； at the desire
of Mr。 Osborne； was kept a profound secret from the public … the only
persons entrusted with the design being those actually engaged in the
construction of the machine； which was built （under the
superintendence of Mr。 Mason； Mr。 Holland； Sir Everard Bringhurst；
and Mr。 Osborne；） at the seat of the latter gentleman near
Penstruthal； in Wales。 Mr。 Henson； accompanied by his friend Mr。
Ainsworth； was admitted to a private view of the balloon； on Saturday
last … when the two gentlemen made final arrangements to be included
in the adventure。 We are not informed for what reason the two seamen
were also included in the party … but； in the course of a day or two；
we shall put our readers in possession of the minutest particulars
respecting this extraordinary voyage。
〃The balloon is composed of silk； varnished with the liquid gum
caoutchouc。 It is of vast dimensions； containing more than 40；000
cubic feet of gas ； but as coal gas was employed in place of the
more expensive and inconvenient hydrogen； the supporting power of the
machine； when fully inflated； and immediately after inflation； is not
more than about 2500 pounds。 The coal gas is not only much less
costly； but is easily procured and managed。
〃For its introduction into common use for purposes of
aerostation； we are indebted to Mr。 Charles Green。 Up to his
discovery； the process of inflation was not only exceedingly
expensive； but uncertain。 Two； and even three days； have frequently
been wasted in futile attempts to procure a sufficiency of hydrogen
to fill a balloon； from which it had great tendency to escape； owing
to its extreme subtlety； and its affinity for the surrounding
atmosphere。 In a balloon sufficiently perfect to retain its contents
of coal…gas unaltered； in quantity or amount； for six months； an
equal quantity of hydrogen could not be maintained in equal purity
for six weeks。
〃The supporting power being estimated at 2500 pounds； and the
united weights of the party amounting only to about 1200； there was
left a surplus of 1300； of which again 1200 was exhausted by ballast；
arranged in bags of different sizes； with their respective weights
marked upon them … by cordage； barometers； telescopes； barrels
containing provision for a fortnight； water…casks； cloaks；
carpet…bags； and various other indispensable matters； including a
coffee…warmer； contrived for warming coffee by means of slack…lime；
so as to dispense altogether with fire； if it should be judged
prudent to do so。 All these articles； with the exception of the
ballast； and a few trifles； were suspended from the hoop overhead。
The car is much smaller and lighter； in proportion； than the one
appended to the model。 It is formed of a light wicker； and is
wonderfully strong； for so frail looking a machine。 Its rim is about
four feet deep。 The rudder is also very much larger； in proportion；
than that of the model ； an