Compressed Air for Saving Life at Sea and other Purposes.
Year: 1888

page_text: Compressed Air for Saving Life at Sea and other Purposes.
I, JOHN D'ARCY-IRVINE Retired Commander, Royal Navy, of Sutton, County
Dublin do hereby declare the nature of this invention to be as follows :―
The object of my invention is to throw a line, cord or rope to a distance by means
of Compressed-Air, for saving life at Sea & other purposes.
Heretofore lines have
been thrown by firing from a Gun or by means of the well known rocket apparatus ;
but such means are often found inconvenient of application, owing to the weight and
quantity of apparatus required, and especially unsuitable for discharging from life
boats, or from Wrecks on to the shore, and in many other cases.
In carrying out my invention I use a species of "Air Gun," into the barrel of
which is inserted a rod projectile. The front end of the projectile extends slightly
from the muzzle of the gun, when the projectile is "home." In the projecting end
an eye is formed, through which a line or cord is passed, extending lengthways along
and outside the barrel of the gun, at each side thereof, and attached to a ring or loop
large enough to slip over the outside of the barrel, the length of these Cords being
such that when stretched the ring or loop will embrace the projectile a short
distance from its base when out of the gun. To the ring or loop is attached one end
of the line to be thrown, and the line may be wound round a bobbin, faked, or other-
wise arranged, alongside or near the Apparatus. The ring or cord attachment are
provided in order that when the projectile is in flight the pull on the line may be
near the base, so as to prevent the projectile turning over in its flight. The ring or
loop is made adjustable, so that it can be set at any distance from the base that is
found to be the best. At the breech end of the barrel a globe, cylinder, or other
form of air reservoir is fixed. The base of the projectile is provided with a screw
taking into a nut in the air reservoir. The screw and nut are partially cut away, so
that the projectile may be pushed in until a seating thereon is brought close up to a
seating in front of the nut,-when, by a quarter turn in the nut, or thereabouts, the
seating on the projectile is drawn up, air tight, against the seating in the nut, and the
projectile thus held firmly in position.

page_text: When the air-reservoir is filled to the desired pressure, the apparatus is in position
for being discharged: By turning the nut or screw round until the full portion of the
screw is opposite the cut away portion of the nut, the projectile is freed from its
hold by the screw, and the air pressure then drives it forward, carrying the line along
with it. The projectile is made of a hollow tubular form, closed at both ends, with
the exception of a small hole in its base, throw which the hollow projectile gets
filled with Compressed-air at the same time that the reservoir is being charged.
The escape of this air, during flight, from the small hole in the base of the
projectile, assists the flight of the latter after it has been discharged from the
* Gun."
The "Gun" may be mounted in any suitable or convenient way, according to the
purpose it may be intended to serve.
Detached air reservoirs or cartridges" may be also employed, 50 arranged as to
be readily attached to or inserted into the "Gun""
Instead of the screw and nut as described a key, wedge, or any other suitable.
locking and unlocking gear may be applied.
In place of the Globe a Cylinder the hollow projectile itself may be made to
serve as the Cartridge or Air reservoir, being in this case left full open at the
base.
For short distances, as, for instance, for throwing a line into the window of a build-
ing on fire in order to haul up a fire escape, or for throwing a line over a chimney, as
is sometimes necessary when executing repairs, or fixing lightning conductors, a solid
rod may be used as the projectile, the air being admitted to the barrel by opening
a tap.
Dated this 2nd day of February 1888.

page_text: Apparatus
Wg a G
a Distance by
Compressed Air for Saving Life at Sea and other Purposes.
I, JOHN D'ARCY-IRVINE formerly of 1 St. Fenton's Terrace, Sutton, Dublin, and
now residing at Harbour House, Howth in the County of Dublin, Ireland, Retired
Commander Royal Navy, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
The object of my Invention is to throw a line, cord, or rope to a distance by
means of compressed air, or other suitable elastic force for saving life at sea,
throwing a line across a stream, or ravine, or into a building on fire, and other similar
purposes.
Heretofore lines have been thrown by firing from a gun or by means of the well
known rocket apparatus but such means are often found inconvenient of application
owing to the weight and quantity of apparatus required, and are especially unsuitable
for discharging from life boats or from wrecks to the shore and in many other
cases.
In carrying out my Invention I use a species of air gun, into the barrel of which
is inserted a projectile the front end of which extends slightly from the muzzle of the
gun when in position for firing, and carries a line or cord, the free ends of which
extend longitudinally along the outside of the barrel of the gun and passe through a
collar or ring large enough to slip over the outside of the barrel.
The ends of the cord, or line are then knotted together and to the loop thus formed
is secured the line to be thrown which is arranged conveniently on a bobbin or faked,
or otherwise in close proximity to the Apparatus.
The construction of the projectile and gun, and manner of admitting compressed
air, as also the method of holding and discharging the projectile will be more
readily understood on reference to the accompanying Drawings of which I attach
two sheets.
Fig. 1 is an elevation of the gun, and disengaging gear with the projectile inserted
in position Fig. 2 is a sectional plan of Fig. 1-Fig. 3 is a sectional elevation
of the breech piece showing a modification of the base end of the projectile.-Figs. 4
and 5 show plan and side views of the projectile when free from the gun; Fig. 6 is a
general view of the gun on its stand, with cop, or bobbin underneath and showing the
projectile in flight, and Fig. 7 is a detail view (enlarged scale) of the disengaging
gear hereinafter more fully described.
Similar letters of reference indicate corresponding parts in each of the several
views.

page_text: A, shows the gun, in the breech of which is formed the air chamber b, which is
filled with compressed air through the opening c, the air being retained in the gun
by the screw jamb valve d;-B shows the projectile which is hollow and closed
at its head, or front end while its base is open as shown in Fig. 2, or provided
with a small aperture e, as in Fig. 3, through which it is filled with compressed
air at the same time that the gun is being charged so that the escape of this.
air may accelerate the flight of the projectile after it has been discharged from the
gun.
The head of the projectile is provided with an eye f, through which the line is
passed, the ends of the line are then passed through, and made fast to the collar i,
which latter is slipped loosely over the barrel so that when the projectile leaves
the gun the pull on the line will be near its base and the tendency to turn over
in its flight thereby prevented.
The collar may be set so as to be at any distance from the base of the projectile
which may be found most desirable.
For the purpose of holding and disengaging the projectile it is provided at its
base, with a screw thread which screws into the Jaws C, C, (forming a divided
nut) until the shoulder g, on the projectile is tight against the seat or flange g'
formed at the end of the barrel whereby an air tight joint is made.
These Jaws are caused to advance and retire by means of the right and left
quick threaded screws h, h, (Fig. 7) working in the Jaws C, C, and passing
through stuffing boxes in the sides of the air chamber and carry at their
outer extremities a forked lever handle D, by the movement of which the projectile
is held or disengaged at pleasure..
For convenience of workmanship the jaws are made round, and prevented from.
turning by flats formed on the upper part thereof against which the flat end
surface of the screwed cap K, slightly presses; or they may be made square and
fitted into a square recess.
The action of the Invention is briefly as follows:
Having passed the line through the head of the projectile and thence through
the collar (to which latter it is inade fast) the projectile is inserted in the gun
while at the same time the collar is slipped over the barrel.
The lever handle D, is then moved so as to cause the jaws to close in forming
a complete nut en bracing the screwed end of the projectile, a slight turn of which
will then bring its shoulder tight up to its scat g', the gun is now charged
with compressed air to the required extent, and can be thus conveyed to the spot
where it is required, or placed on a life boat. The line to be thrown being then
arranged conveniently, the projectile is ready for discharging, whereupon the lever
handle D, is moved in the reverse direction causing the jaws to retire and thus
disengage the projectile which is then expelled with considerable force by the com-
pressed air, carrying the line with it.
Instead of passing the line through an eye formed in the head of the projectile as
above described, a swivel may be arranged on its head through side holes in which
the line may be passed.
Portable air reservoirs charged with air at high pressure may also be provided with
the gun so that it may be charged, and discharged several times in case of need, or a
small portable air pump may be employed.
The gun may be arranged to discharge from a stand as in Fig. 6, or from any suit-
able carriage or in any way found convenient for the purpose to which it.
may be applied. It may also be constructed on a small scale to discharge from the
shoulder.
Instead of compressed air any suitable compressed gas may be used, as for instance
the compressed hydrogen used for balloons.
That portion of my invention relating to the cord attachment and the collar i,
passing outside the barrel of the gun may also be applied in the case of projectiles
with lines fired from ordinary guns.

page_text: Having now described and ascertained the nature of my said Invention and
in what manner the same is to be performed I would have it understood that I do
not confine myself to the precise details herein described and illustrated as the same
may be variously modified without departing from the principle of my Invention-but
what I claim is
First. In apparatus for throwing a line or cord for the purpose, or purposes herein
described the general arrangement and combination of parts substantially as specified
and set forth.
Second.--The mode of attaching the line or cord in combination with the collar i
whereby the pull on the line or cord when the projectile is in flight is maintained at
or near the base of projectile in the manner substantially as described.
Third. The method whereby the projectile is held and disengaged and mode of
making the projectile air tight against its seat g¹, substantially as set forth.
Fourth. The hollow forin of projectile constructed either as in Fig. 2 or with
contracted orifice at its base as in Fig. 3 for the purpose and in the manner substan-
tially as herein specified and set forth.
Dated this 28th day of November 1888.