AN IMPROVED FORM OF HYDROPNEUMATIC ENGINE
Year: 1884

page_text: I JOHN WILLIAM GORDON of 28 Pembury Grove Lower Clapton in the County
of Middlesex Gentleman do hereby declare the nature of my invention for AN
IMPROVED FORM OF HYDROPNEUMATIC ENGINE to be as follows, that is to say:-
For this purpose I take advantage of the cohesion of the liquid in the manner
hereinafter described. For simplicity sake I speak in this description of water and
of air as the two fluids employed; but without intending thereby to limit the
application of my invention.
My apparatus consists essentially of two parts, a water tube and an air tube.
The air tube does not communicate directly with the water tube; which in this
connexion I call a condensing tube; but with a common chamber at such a point
thereof as to be secure from drawing the water brought down by the condensing
tube. A waste pipe communicating at a lower level with the common chamber
carries off this water At the upper end of the condensing pipe water is introduced
in quantity too small to fill the tube with a continuous column of water through
its whole length-Suitable incans being taken to cause the water on its admission
to expand in a film across the tube (which must be of sufficiently small boré to
allow the water to assume and maintain this form under the influence of capillary
attraction) it will pass down in a longer or shorter column driving before it the
intercepted air. The supply of water being kept up the whole tube may be kept
filled with descending alternate columns or films of water and, of air. This air is
compressed in the course of its descent. It enters the chamber with a density
proportioned to the height of the superincumbent column of water in the
condensing tube, and being carried off by the air tube is available for any
purpose to which it may be put.
The condensing tube of this description may be combined with any number of
others in one system to procure a sufficient supply of air.
In speaking of tubes of small bore in the foregoing 'description I have used
words particularly appropriate to the ordinary tube of cylindrical form But it is
expressly intended to provide alternatively for the use of tubes of other forms
than this.

page_text: An improved forHI
I JOHN WILLIAM GORDON late of 28 Pembury Grove in the County of Middlesex
but now of 2 Sunnyside Villas Queens Down Road Lower Clapton in the said
County, Gentleman do hereby declare the nature of my invention for AN IMPROVED
FORM OF HYDRO-PNEUMATIC ENGINE and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement :-
As to its nature:-It is an invention for communicating the energy of a falling
liquid to a gas which is thereby compressed, with a view to its being afterwards.
usefully employed in any form of machine which can be driven by such, com-
pressed gas.
My method of doing this is as follows.
I take a tube having any desired sectional form; say, for example, of circular
section, that is to say an ordinary cylindrical tube. At the upper end of this
tube I make a constriction at a short distance below the top. This may very
conveniently be done by introducing a very short length, (perhaps half an inch,)
of a tube of still smaller bore, through which all the liquid introduced. above it
must pass. I then supply water, or other liquid, to the main tube-above the
constriction; which I term the "neck"; in less quantity than the main tube itself
is capable of carrying away, but in quantity sufficient to fill a tube of the size used
for the neck. This is shewn in Fig. I.
The action, then is as follows:-The water, or other liquid entering the neck of
the tube, which I call a "condensing tube," fills up the entire aperture. When
flowing out at the lower end of the neck it is introduced into the centre of the
main tube, & being by the capillary attraction of the sides & shoulder caused to
expand so as to fill the larger aperture of the main tube. it forms into a small
column or film, upheld by the subjacent gas in the condensing tube. As this
column increases in length a point is reached at which its pressure is sufficient to
overcome the resistance from below, and then becoming detached from the neck of
the tube it descends, being in fact a small fluid piston actuated by its own gravity.
In this way it drives the intercepted gas beneath it & compresses it in so doing.
The gas thus compressed is received into a suitable chamber with which the foot of
the condensing tube may be connected with, or in some cases without, a gas trap.
The condensing tube. as above described may be of any desired length or
material: As to it sectional area, no" definite limit of size can be assigned, the
determining consideration being, as above indicated, that the liquid surface shall be
sufficiently coherent to prevent bubbling of the gas through the liquid. My own
experiments appear to shew that when water is used as the compressing liquid &
the gas acted upon is air, the limit of size for a cylindrical glass tube is about one
fourth of an inch diameter.
When the supply of air condensed by one tube would be inadequate to the
purpose in view any number of tubes may be combined in one machine.
My invention comprises also a form of Governor valve for regulating the supply
of liquid to a tube or system of tubes of the above description The object is

page_text: to prevent an over supply of liquid and consequent waste of energy. For this
purpose I use the contrivance shewn in Fig. 2. The liquid, which for directness'
sake I call water, is maintained at an invariable level in the cistern from which it
is drawn, by means of a ball-tap or other similar appliance. From this cistern it
is drawn away by the tube marked A in the drawing which leads to an air tight
chamber, & opens at a point lower by any desired depth than the constant level in
the cistern. Another tube carries away the water introduced into this chamber
and feeds it to the condensing tube. Again a third tube, marked B in the drawing,
puts the closed chamber into communication with the reservoir of compressed air.
From this description it will be clear that the gas pressure in the chamber will
always be equal to that in the reservoir & that when this pressure rises to a point
equal to that due to the difference in level between the constant. level in the cistern
& the peripheral end of the tube A. the further flow of water through that tube
will be arrested nor can it be renewed until the pressure has fallen below this
point.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
1. The use of a condensing tube and Governor valve of the description and for
the purposes herein specified whether separately or in combination and of a system
of such tubes for the like purposes.
2. The use in particular of such apparatus for the purpose of driving clocks
or signals or any mechanism requiring only a small motive force.