of my invention consists of an apparatus so
constructed as to offer a very extended surface or plane of a light yet
strong construction, which will have the same relation to the general
machine which the extended wings of a bird have to the body when a bird
is skimming in the air; but in place of the movement or power for onward
progress being obtained by movement of the extended surface or plane, as
is the case with the wings of birds, I apply suitable paddle-wheels
or other proper mechanical propellers worked by a steam or other
sufficiently light engine, and thus obtain the requisite power for
onward movement to the plane or extended surface; and in order to give
control as to the upward and downward direction of such a machine I
apply a tail to the extended surface which is capable of being inclined
or raised, so that when the power is acting to propel the machine, by
inclining the tail upwards, the resistance offered by the air will
cause the machine to rise on the air; and, on the contrary, when the
inclination of the tail is reversed, the machine will immediately be
propelled downwards, and pass through a plane more or less inclined to
the horizon as the inclination of the tail is greater or less; and in
order to guide the machine as to the lateral direction which it shall
take, I apply a vertical rudder or second tail, and, according as the
same is inclined in one direction or the other, so will be the direction
of the machine.'

The machine in question was very large, and differed very little from
the modern monoplane; the materials were to be spars of bamboo and
hollow wood, with diagonal wire bracing. The surface of the planes was
to amount to 4,500 square feet, and the tail, triangular in form (here
modern practice diverges) was to be 1,500 square feet. The inventor
estimated that there would be a sustaining power of half a pound per
square foot, and the driving power was to be supplied by a steam engine
of 25 to 30 horse-power, driving two six-bladed propellers. Henson was
largely dependent on Stringfellow for many details of his design, more
especially with regard to the construction of the engine.

The publication of the patent attracted a great amount of public
attention, and the illustrations in contemporary journals, representing
the machine flying over the pyramids and the Channel, anticipated fact
by sixty years and more; the scientific world was divided, as it was
up to the actual accomplishment of