IMPROVEMENTS IN THE MODE OF CONSTRUCTING VESSELS FOR CONTAINING AIR APPLICABLE TO THE PURPOSE OF RAISING SUNKEN OR LIFTING FLOATING BODIES UNDER OR IN THE WATER, AND OF FASTENING SUCH VESSELS TO CHAINS OR OTHER MACHINERY OR APPARATUS, TO BE USED FOR RAISING OR LIFTING SUCH BODIES
Year: 1839

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
HENRY BURKE, of Shoreditch, in the County of Middlesex, Hat Manufacturer,
send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Third day of October, in the third year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said William
Henry Burke, Her especial licence, full power, sole privilege and authority,
that I, the said William Henry Burke, my exors, admors, and assigns, or such
others as I, the said William Henry Burke, my exors, admors, or assigns, should
at any time agree with, and no others, from time to time and at all times
during the term of years therein expressed, should and lawfully might make,
use, exercise, and vend, within England, Wales, and the Town of Berwick-
upon-Tweed, and also in all Her said Majesty's Colonies and Plantations abroad.
my Invention of "IMPROVEMENTS IN THE MODE OF CONSTRUCTING VESSELS FOR
CONTAINING AIR APPLICABLE TO THE PURPOSE OF RAISING SUNKEN OR LIFTING
FLOATING BODIES UNDER OR IN THE WATER, AND OF FASTENING SUCH VESSELS TO
CHAINS OR OTHER MACHINERY OR APPARATUS, TO BE USED FOR RAISING OR LIFTING
SUCH BODIES;" in which said Letters Patent is contained a proviso that I, the
said William Henry Burke, shall cause a particular description of the nature
of my said Invention, and in what manner the same is to be performed, to be
inrolled in Her said Majesty's High Court of Chancery within six calendar
months next and immediately after the date of the said in part recited Letters
Patent, as in and by the same, reference being thereunto had, will more fully
and at large appear.

page_text: NOW KNOW YE, that in compliance, with the said proviso 1, the said
William Henry Burke, do hereby declare the nature of my Invention, and
the manner in which the same is to be performed, are fully described and
ascertained in and by the following statement thereof (that is to say) :-
My Invention relates to the construction of that description of air vessels
which are made of flexible air and waterproof fabrics, which have been pro-
posed to be used in raising sunken and lifting ships and vessels and bodies in
the water. The nature of combining waterproof fabrics being well known, and
the modes of forming the same into air-tight vessels having been before
practised, more than a general statement of the means to be pursued in
making such vessels will not be required in carrying out this my Invention,
further than to state that the air-tight flexible vessels heretofore made for
such purposes have been cylindrical, and it has been found that in suspending
thereto ships or vessels, or other heavy bodies when in the water, the air-tight
flexible vessels are drawn out of their figure, and owing to the various parts
being made cylindrical, the changing of their figure by tension has been found
to injure the same, and the vessels have been burst; there is moreover
found a disadvantage in employing flexible vessels of a cylindrical section, owing
to the distance which they are necessarily off from the body to be raised, I
therefore make, in the first instance, my flexible air vessel of a heart-shaped
section, and in place of making such vessels all in one compartment as has
been practised heretofore, and that of considerable length compared with the
diameter; I apply one or more partitions in order to divide the length of each
air vessel into compartments of about twelve feet long. The object of this
arrangement, and the benefit thereof will be obvious when it is considered
that in using a flexible air vessel, say from twenty to thirty feet long, should
it not be fixed in a truly horizontal position to the sunken ship or other body,
the air, when the air it is pumped in would rise to the most elevated part of
the air vessel, and it will, under some circumstances, be very difficult when the
air vessel consists of only one chamber to fill it in all parts, but when it con-
sists of several compartments with branch air-pipes from the main air-pipe
all the compartments will go on filling equally at the same time, and thus an
air vessel of a given size will be thereby more readily and completely brought
into full action; or adopting the same principles of improvement, I operate
with separate air vessels in lieu of the larger vessels divided into compartments,
placing them contiguously to each other in covers of canvass or network as
next herein-after described, as I should place the larger vessel, when that is
used. In making such air vessels, in place of affixing the strong bands and
chains directly, to the flexible air-tiglit vessels themselves I apply a strong

page_text: external canvass cover or network of the same shape as the flexible air vessel,
and affix the strong bands and chains around the same, and thereby prevent
any unequal strain taking place on any particular part of the air vessel, which
is very liable to rend the same when the bands and chains are connected
directly to the fabric of the air vessels; and it is by giving to the air vessels
the figure above described, and combined with the mode of using an external
case or cover, to which the bands and chains are attached, by which the
apparatus is affixed to a sunken vessel are attached, that a considerable
advantage will be gained in applying flexible air vessels to the raising of
sunken or other bodies by chains or such like means when in the water.
Both
ends of the bands or chains, which, according to the present system, extend
below the bottom of the air vessels to such lengths as may be required for their
attachment to the purchase chain encircling the ship or other body about to
be lifted, may upon my plan be kept at their proper distances, and in their
proper situation by passing them either through or round a beam or bar of
wood, iron, or other metal in one length, or divided into parts, and securing or
stopping them in their position. This beam or bar will also keep the pur-
chase chain and the lower part of the lifting apparatus formed of the air
vessels and covering, which together I call a caissoon distended, and will
make the strain more equable. But the main, feature of iny Invention is
the constructing. flexible air vessels for such purposes with an opening to
allow of the passing off of air therefrom, as the flexible air vessel rises to the
surface of the water. And it may be desirable to point out the object of this
part of my. Invention. It will be evident that in using flexible air-tight
vessels in order to distend them when under the pressure of a considerable
column of water, the air forced therein must become as dense as the pressure
of the surrounding water, thus, supposing a flexible, air vessel to be at a depth
below the surface of the water, equal to from thirty to thirty-two feet, there
will be a pressure of about fifteen pounds on each square inch of the surface.
And in order to distend the flexible vessel, with air, the air must be under a
pressure of fifteen pounds on each square inch of the surface; whereas at the
surface of the water the air would not be in a compressed, state, but would be
equal to the surrounding atmosphere. Now it will be evident that if a flexible
air-tight vessel were inflated at a depth below water equal to from thirty to
thirty-two feet, and were then to rise to the surface of the water, it would in
rising be subjected to an external pressure decreasing from fifteen pounds on
each square inch of the surface to no external pressure by the time it arrives
upon the surface, and there would consequently be a reaction of the air on
the inside tending to burst the vessel equal to the pressure required to con-

page_text: dense the air into the vessel at the depth below the water at which it had
been inflated; and this pressure would be greater or less according as the
depth of water exceeded or was less than from thirty to thirty-two feet; and it
must be evident that such flexible air vessels cannot when made air-tight in
all parts, as has been the case heretofore, be so safely employed when the
sunken ship or body to be raised is at any considerable depth. In constructing
flexible air vessels therefore, according to my Invention, whatever be their
shape, in place of having them air-tight at all parts as heretofore, I form an
opening at that part of the flexible air vessel which will be in the lowest posi-
tion when attached to the sunken ship or vessel, or other body, and for large
air vessels a hole or opening of about ten inches in diameter will be sufficient,
and if the vessels are divided into compartments, there must be a hole to
each. The margins of these openings are to be bound and made strong to
prevent the fabric splitting. The effect of using vessels having such openings
will be, that when the air is forced in, the same will inflate the air vessels and
distend them; and any excess of air forced into the air vessels would pass off,
and there would be no liability to the risque of bursting the vessel by an excess
of air being forced in, a risque which is incurred under the present system,
from the difficulty of the persons pumping knowing when the air vessels are
full. And it will be evident, moreover, that the air vessels constructed with
the escape will not in rising upward from below be prejudicially acted on by
the expansion of the air within, because as the air vessels rise towards the
surface of the water, the air therein in its expansion passing off by the
openings, at every point of time the air on the inside would be found to be
equally dense, or nearly so, with the pressure of water without, and the air
vessels when they arrive to the surface of the water will simply be inflated with
a pressure of air equal or nearly so to the atmosphere. In order to prevent
the premature escape of the air pumped into the air vessels in case they
should assume such a position under the water that the opening is not at the
lowest part, I generally attach to the margin of the opening a pipe of flexible
material of sufficient length to ensure a complete inflation. In conclusion, I
would remark, that I do not claim the application of flexible air vessels to
The purposes herein described, they being well understood, but only claim the
modifications-or-improvements herein described.
In witness whereof, I, the said William Henry Burke, have hereunto
set my hand and seal, this Third day of April, in the year of our Lord
One thousand eight hundred and forty.
W. H. BURKE. (L.S.)

page_text: AND BE IT REMEMBERED, that on the Third day of April, in the year
of our Lord 1840, the aforesaid William Henry Burke came before our said
Lady the Queen in Her Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained and specified, in form
above written. And also the Specification aforesaid was stamped according to
the tenor of the Statute made for that purpose.