IMPROVEMENTS IN LIFE-PRESERVING MATTRESSES FOR SAVING LIFE. AT SEA
Year: 1871

page_text: LETTERS PATENT to Joseph Birt, junior, and Alfred William Birt,
both of 4, Dock Street, in the County of Middlesex, for the Inven-
tion of "IMPROVEMENTS IN LIFE-PRESERVING MATTRESSES FOR SAVING LIFE.
AT SEA."
7
Sealed the 30th April 1872, and dated the 16th November 1871.
PROVISIONAL SPECIFICATION left by the said Joseph Birt and Alfred
William Birt at the Office of the Commissioners of Patents, with
their Petition, on the 16th November 1871.
•
We, JOSEPH BIRT, junior, and ALFRED WILLIAM BIRT, both of 4,
Dock Street, in the County of Middlesex, do hereby declare the nature
of the said Invention for “IMPROVEMENTS IN LIFE-PRESERVING MATTRESSES
FOR SAVING LIFE AT SEA," to be as follows:-
This Invention has for its object improvements in life-preserving
mattresses for saving life at sea. For this purpose we employ granulated

page_text: cork as the stuffing material, and construct the mattress with a joint
down the centra lengthwise, so that it may be folded together when
required for use as a life preserver, and when so folded its two ends are
fixed together by fastenings provided for the purpose. The life-
preserving mattress then forms an annular float, and the person using it
places it around him underneath his arms, and to prevent the possibility
of his being washed out of it when in the sea he places his arms through
arm straps provided for the purpose.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Joseph Birt and Alfred William Birt in the Great
Seal Patent Office on the 15th May 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JOSEPH
BIRT, junior, and ALFRED WILLIAM BIRT, both of 4, Dock Street,
in the County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixteenth day of November, in the year
of our Lord One thousand eight hundred and seventy-one, in the thirty-
fifth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto us, the said Joseph Birt and Alfred William Birt, Her
special license that we, the said Joseph Birt and Alfred William Birt,
our executors, administrators, and assigns, or such others as we,
the said Joseph Birt and Alfred William Birt, our executors, adminis-
trators, and assigns, should at any time agree with, and no others, from
time to time and at all times thereafter during the term therein
expressed, should and lawfully might make, use, exercise, and vend,
within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN LIFE-
PRESERVING MATTRESSES FOR SAVING LIFE AT SEA," upon the condition
(amongst others) that we, the said Joseph Birt and Alfred William Birt,
our executors or administrators, by an instrument in writing under our
or their hands and seals, or under the hand and seal of one of us
or them, should particularly describe and ascertain the nature of the

page_text: said Invention, and in what manner the same was to be performed,
and cause the same to be filed in the Great Seal Patent Office within
six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said Joseph Birt, on behalf of myself
and the said Alfred William Birt, do hereby declare the nature of the
said Invention, and in what manner the same is to be performed, to
be particularly described and ascertained in and by the following
statement thereof, that is to say:—
This Invention has for its object improvements in life-preserving
mattresses for saving life at sea. For this purpose we employ granulated
cork as the stuffing material, and construct the mattress with a joint
down the centre lengthwise, so that it may be folded together when
required for use as a life preserver, and when so folded its two ends are
fixed together by fastenings provided for the purpose. The life pre-
serving mattress then forms an annular float, and the person using it
places it around him underneath his arms, and to prevent the possibility
of his being washed out of it when in the sea he places his arms through
arm straps provided for the purpose.
Figure 1 is an under side view of a life-preserving mattress constructed
according to our Invention, as it appears when laid out flat. Figure 2
is an end view of the same, clearly showing the longitudinal joint at a.
The mattress is provided with strings or tapes b, b, for tying it together
when folded for use as a life preserver; c, c, are other strings or tapes to
serve as arm and breast straps. Figure 3 represents the mattress
prepared for use as a life preserver. The cork with which the mattress
is stuffed is ground by machinery, and after the dust is removed the
grains are of small size; mattresses stuffed with this material have a
soft elastic surface; rib pieces are inserted to prevent the cork from
shifting.

page_text: Having thus described the nature of our said Invention and the
manner of performing the same, we would have it understood that we
claim the construction of life-preserving mattresses substantially as
described.
In witness whereof, I, the said J. Birt, j', have hereunto set 5
my hand and seal, this Eleventh day of May, in the year of
our Lord One thousand eight hundred and seventy-two.