CERTAIN IMPROVEMENTS IN PROPELLING AND SUSTAINING BALLOONS AND AERIAL MACHINES IN THE AIR
Year: 1861

page_text: PROVISIONAL SPECIFICATION left by David Stephens Brown at the
Office of the Commissioners of Patents, with his Petition, on the 10th
October 1861.
I, DAVID STEPHENS BROWN, of Eton Lodge, Ashby Road, Islington, in the
County of Middlesex, Gentleman, do hereby declare the nature of the said
Invention for "CERTAIN IMPROVEMENTS IN PROPELLING AND SUSTAINING BALLOONS
AND AERIAL MACHINES IN THE AIR," to be as follows:-
The employment of ammonia and carbonic acid to work engines, similar to
steam engines, for the purpose of giving motion to fans like screw propellers,
with a view of propelling and sustaining balloons and aerial machines in the
air. To accomplish this the ammonia and carbonic acid are to be first
reduced by pressure to liquid or solid states and placed in condensers made of
a number of tubes arranged parallel to one another and united by some
membraneous substance. The condensers are then to be suspended from the
balloon in a transverse manner, like flags bung from a horizontal rope, the
the effect of which will be, when the balloon is propelled forward, to cause
them to drag behind, by which means the balloon will be relieved of a great
part of their weight, which will be borne by the air; and this contrivance will
also facilitate the conversion of the ammonia and carbonic acid into gaseous
states by bringing a current of air into contact with the outside of the con-
densers. So fast as the gases are produced they are to be conveyed to the
engines, and after doing duty there are to be injected into the body of the
balloon, and the bydrogen gas, steam, or heated air that may be present is to
be allowed to escape in order to make room for them. If hydrogen, it might be

page_text: burnt for fuel as it flows out of the balloon, with a view of augmenting the
engine power, either by aiding in the production of the said gases, superheating
them, or in generating steam. To prevent the gases from mixing two collapsed
balloons are to be placed in the main one to receive the ammoniacal and
carbonic acid gases. The reason why two gases are used instead of ammonia
alone is to preserve the uniform buoyancy of the balloon as the hydrogen
escapes. When the voyage is completed the gases are to be pumped from the
balloon again into condensers by some cheap mechanical power, so that they
may be used over and over again. The balloon is to be made in an oblong
form horizontally, its two ends being brought to points from the centre by
curved lines, such as would be produced by two equal segments of a circle
placed base to base, and where the greatest breadth would be to the length as
is the proportion of about one to ten; and it is to be made sufficiently rigid by
the condensation of the gas or gases in it to enable a screw propeller to be
fitted to one of its ends and a rudder to the other; the said ends may be
further strengthened by longitudinal tubes arranged round them, and which
tubes may form part of the condensers alluded to. The rudder is to be formed
of a horizontal plane fixed to a vertical one, so as to act vertically as well as
.horizontally. When the sustaining power is obtained by mechanical action two
horizontal fans or screws are to be placed above a car formed like a life-boat
or canoe. The fans are to receive their first motion from springs, the effect of
which will be to raise the machine until the springs become exhausted, when
the machine will descend, and in doing so the air, by its reaction on the fans,
will cause them to revolye in an opposite direction, and thus partly rewind up
the springs; and to complete the winding-up an ammoniacal gas engine,
similar to what has already been described, is to be employed as well as to
give motion to a vertical screw propeller placed at one end of the car, a rudder
being placed at the other. The car is to be made of inflated air-tight cloth or
other substance like india-rubber cushions, condensed air or gas giving rigidity
to the material. The fans are also to be made of cloth or some membraneous
substance, either inflated or not, and to be held in position by being surrounded
at their peripheries by inflated rings rendered rigid by condensed air or gas.
The changes of temperature and and atmospheric pressure that will be
encountered by the machire in its ascent and descent are to be made
available in augmenting the motive power.