A NEW MODE OF AND APPARATUS FOR PRODUCING AND OBTAINING MOTIVE POWER
Year: 1860

page_text: PROVISIONAL SPECIFICATION left by Bartolommeo Predavalle at the
Office of the Commissioners of Patents, with his Petition, on the 15th
June 1860.
I, BARTOLOMMEO PREDAVALLE, of Bloomsbury Street, Bloomsbury Square,
in the County of Middlesex, Civil Engineer, do hereby declare the nature of
the said Invention for "A NEW MODE OF AND APPARATUS FOR PRODUCING AND
OBTAINING MOTIVE POWER," to be as follows:-
My Invention consists in a constant atmospheric pressure imparting its
downward gravitation on a vertical column of liquid, communicating with an
hollow piston suspended in a cylinder and surrounded by a vacuum.
DESCRIPTION OF THE APPARATUS.
At one extremity of an india-rubber tube is fixed a circular frame containing
a valve opening outside, and at about an inch from this a plate of the same.
diameter, as the valve is secured in order to form a kind of an hollow air-tight
piston sack or bag. This extremity of the india-rubber tube is then introduced
in a cylinder, open at top and shut up at bottom, about half an inch larger than
the piston. The other extremity of the india-rubber tube is then turned over
and fastened all round the upper open part of the cylinder, so that the bottom
of the piston or the valve will never reach the bottom of the cylinder by any
extension whatever produced by the action of the atmospheric pressure on the
flexibility of the india-rubber tube, but be always suspended. From the outside

page_text: bottom of the cylinder an air-tight rod is introduced supporting the valve
which rod is outside of the cylinder connected with the resistance to be over-
In the plate of the piston a thin pipe is vertically fixed communicating
with the interior of the piston, and having a stop-cock at top. In whatever
part of the cylinder a stop-cock is fixed connected with an exhausting pump
and a vertical vacuum gauge in another part. The pressure of the liquid
must be less about one pound every square inch than the pressure of the
atmosphere on the vacuum, in order that the pressure of the liquid from the
bottom to the top in the hollow piston may be not only constantly neutralized,
but also overwhelmed by the atmospheric pressure, the excess of which will
maintain constantly the apparatus as a cover on the valve, thus making the
downward gravitation of the liquid effectively acting on the valve of the
piston. When the vacuum is made in the cylinder, and the vertical pipe filled
with liquid, the pressure of the atmosphere through the thin or small pipe
will impart a constant impulsive force to the valve and to the rod touching it
in proportion to the height of the column of liquid and the vacuum produced,
and the apparatus will move according to the adopted contrivance, and may be
applied as the piston of a steam engine, in order to produce an alternate
vertical motion or a constant horizontal one, provided the liquid pipe should
be maintained always in a vertical direction. When the air is introduced in
the cylinder and the stop-cock in the liquid pipe is shut up, the apparatus
remains in a state of equilibrium or rest, having cut off the outside impulsive
force.