PONTOONS OR AIR-BAGS FOR RAISING VESSELS OR SUBMERGED WEIGHTS
Year: 1879

page_text: Finchley, in the County of
IMPROVEMENTS IN FLEXIBLE
LETTERS PATENT to James Pullar, of North
Middlesex, Gentleman, for the Invention of
PONTOONS OR AIR-BAGS FOR RAISING VESSELS OR SUBMERGED WEIGHTS."
Sealed the 6th May 1879, and dated the 2nd January 1879.
PROVISIONAL SPECIFICATION left by the said James Pullar at the Office of
the Commissioners of Patents on the 2nd January 1879.
6:
JAMES PULLAR, of North Finchley, in the County of Middlesex, Gentleman.
IMPROVEMENTS IN FLEXIBLE PONTOONS OR AIR-BAGS FOR RAISING VESSELS OR.
SUBMERGED WEIGHTS."
1
The object of this Invention is the construction of reliable and efficient
pontoons for the purpose as set forth in the title, those portions at present in use
being liable to certain defects which detract from their usefulness.
This Invention consists as follows:-I take cloth, by preference, 'especially
prepared for the purpose, and with layers of india rubber or other elastic material
between two or more layers of cloth, or placed above or below such layers of cloth,
or cloth saturated or impermeated with water or air resisting material in solution.
In all cases such cloth or the combined thickness thereof is to be of sufficient
strength to bear the pressure required.
The pontoons I construct of the material or materials above mentioned or of any
suitable water and air proof material in a form, by preference, approaching that of
a cylinder, having hemispherical, elliptical, or other suitably shaped ends. I fit
them with self acting relief valves capable of being regulated to any required
pressure.
These valves are one or two in number, but their number may be increased
should it be found that from any cause an improved result would follow.
An inlet pipe with check valve or stop cock, or both if necessary, is fitted centri-
cally on the top of the cylinder. To this is connected interiorly or within the cylinder
two tubes, which tubes are for the purpose of distributing equally air within the
cylinder. Each end of the cylinder is or may be fitted with a similar arrangement
for the introduction of air in such cases where the inlet at the top would be useless.
I also fit each end of the cylinder internally and externally with a circular or other
suitably shaped plate or washer.

page_text: The two plates or washers are bolted together. In the centre of this arrange-
ment of plates or washers I fit an inlet pipe with check valve or stop cock, or both,
to which may be connected, as described above, the two tubes for the purpose of
distributing equally the air. For the purpose of keeping the pontoon in its place.
in the netting so as to facilate its inflation I fix exteriorly ring bolts, whose ends
passing through the said plates or washers through which rings, ropes, or chains
are passed attached to or forming part of the netting, I fit the inlet and relief valve
flanges with the same arrangement.
The pontoons thus constructed are inflated by means of an air pump.
The pontoons are if necessary covered with netting, and such netting is of suitable
sized mesh, and attached to an iron or other bar of suitable strength to take the
weight of the object to be lifted.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said James Pullar in the Great Seal Patent Office on the 1st July
1879.
JAMES PULLAR, of North Finchley, in the County of Middlesex, Gentleman.
"IMPROVEMENTS IN FLEXIBLE PONTOONS OR AIR BAGS FOR RAISING VESSELS OR
SUBMERGED WEIGHTS."
The object of this Invention is the construction of reliable and efficient pontoons
for the purpose as set forth in the title, those pontoons at present in use being liable
to certain defects which detract from their usefulness.
This Invention consists as follows:-I take cloth, by preference, especially
prepared for the purpose, and with layers of india rubber or other suitable elastic
material between two or more layers of cloth, or placed above or below such layers
of cloth, or cloth saturated with water resisting material or air resisting material in
solution, so as to be impermeable. In all cases such cloth or the combined thicknesses
thereof is to be of sufficient strength to bear the required pressure.
I construct the pontoons of the materials or materials above mentioned or of any
water and air proof material in a form, by preference, approaching that of a cylinder
having elliptical or other suitably shaped ends. I fit such pontoons with self acting
relief valves capable of being regulated to any required pressure.
I fit one or two of these valves to cach pontoon, but their number may be
increased should it be found that from any cause an improved result would
follow.
An inlet pipe with check valve or stop cock, or both if necessary, is fitted
centrically on the top of the cylinder. To the pipe is connected interiorly or
within the cylinder two tubes, which tubes are for the purpose of distributing
equally air within the cylinder. Each end of the cylinder is or may be fitted with a
similar arrangement for the introduction of air in such cases where the inlet at the
top would be useless; I also fit each end of the cylinder internally and externally
with a circular or other suitably shaped plate or washer. The two plates or
washers are bolted together. In the centre of this arrangement of plates or washers
I fit an inlet pipe with check valve or stop cock, or both, to which may be con-
nected as described above the two tubes for the purpose of distributing equally the
air. For the purpose of keeping the pontoon in its place in the netting with which
it is provided during the process of inflation, and to facilitate that operation I fit
externally ring bolts, their ends passing through the said plates or washers. Through
the rings, ropes, or chains are led, such ropes or chains may be attached to or form
part of the netting. I fit the inlet and relief valve flanges with the same
arrangement.
The pontoons thus constructed are inflated by means of an air pump.
The pontoons are covered with netting of any suitably sized mesh, and they are
attached to an iron or other bar of suitable strength to take the weight of the object
to be lifted.
In order to describe more particularly the nature of my said Invention, and the
means by which the same is carried into effect, this Specification is accompanied by
two Sheets of Drawings, having figures and letters of reference marked thereupon,
the like letter being used to denote a similar or corresponding part in each
Figure.
Figure in the Drawings is a longitudinal sectional view of a pontoon constructed
according to my Invention; Figure 2 is a cross section Figure 3, an external
elevation Figure 4, an end view; Figure 5, a half sectional clevation of the
same. The inlet pipe provided with a relief valve is marked "A"; the two tubes for
the purpose of equalizing the distribution of the air, so that not only during the
inflation, but during the time the raising operations are being carried on, are
marked "B." In the Figure the inlet is shewn at the top of the pontoon, but, as

page_text: herein before explained, its ends may be similarly fitted, the tubes being suitably
placed so as to distribute the air equally, as in the first case. The plates or washers
at each end of the pontoon are marked "C," and the ringbolts for the ropes or
chains "D" Figure 6 is a view to enlarged scale of the valve seating shewing the
way in which it is secured to the material "E" of which the. pontoon is made;
Figure 7 is a top view of the valve seating, shewing the inlet into the pontoon;
Figure 8 is a sectional view of the relief valve. The inlet is marked "F." It will
be seen by Figure 8 that the mouth piece is screwed externally to receive the
tightening ring, and internally for the valve seat. The valve seat consists of grating
perforated guard on top, bottom guide, and guard for valve spindle. The valve is
constructed with hollow spindle and plate, faced with india rubber spring, as shewn
in the Drawing, and is provided with an adjusting bolt.
The plates or washers "C" at each end of the pontoon are shewn separately to an
enlarged scale in Figure 9. Sheet No. II. shows the general arrangement of my
Invention as applied.
The requisite number of pontoons thus constructed and fitted having been attached
in any suitable manner by divers are inflated by means of an air pump or air pumps
carried by a vessel on the surface of the water, and connected with hose pipes
leading to the pontoons. I prefer to use with the air pumps an air receiver fitted
with the necessary safety valves.
Having now particularly described and ascertained the nature of my said
Invention, and the manner in which the same is to be carried into practical effect, I
wish is to be clearly understood that I do not claim the principle of raising vessels or
submerged weights by means of pontoons or air bags covered with netting, but I
claim as my Invention,-
Firstly. The improved construction and general arrangement of pontoons having
relief valves which are self acting, so that they may relieve or let air escape when
the pressure of the water diminishes, as the bag or pontoon arises, and having also
tubes leading from the inlet or inlets for the purpose of distributing equally the air
in its admission, and of maintaining the bag or pontoon in the position desired.
I claim, Secondly. Separately the peculiar construction of the self acting relief
valve, as described in this Specification, and in the accompanying Drawings
illustrated.
I also claim in pontoons or bags for raising vessels or weights the arrangement
of tubes leading from the inlet or inlets, as and for the purpose described and
illustrated.
In witness whercof, I, the said James Pullar, have hereunto set my hand
and seal, the Twenty fifth day of June, in the year of our Lord One
thousand eight hundred and seventy nine.
JAMES PULLAR. (L.S.)