IMPROVEMENTS IN FLOATING MATTRESSES, LIFE-PRESERVERS, BUOYS, AND SIMILAR ARTICLES, WHICH INVENTION IS ALSO APPLICABLE TO BOATS, SHIPS' COMPARTMENTS, AND THE LIKE
Year: 1880

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for an Invention of
"IMPROVEMENTS IN FLOATING MATTRESSES, LIFE-PRESERVERS, BUOYS, AND
SIMILAR ARTICLES, WHICH INVENTION IS ALSO APPLICABLE TO BOATS, SHIPS'
COMPARTMENTS, AND THE LIKE." A communication from abroad by Joseph
Gibbons Hill and John de Hart Harrison, both of Newark, New Jersey, United
States of America, Manufacturers.
COMPLETE SPECIFICATION filed by the said William Robert Lake at the
Office of the Commissioners of Patents on the 4th May 1880.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN FLOATING MATTRESSES,
LIFE-PRESERVERS, BUOYS, AND SIMILAR ARTICLES, WHICH INVENTION IS ALSO
APPLICABLE TO BOATS, SHIPS' COMPARTMENTS, AND THE LIKE." [A communication
from abroad by Joseph Gibbons Hill and John de Hart Harrison, both of Newark,
New Jersey, United States of America, Manufacturers.]
This Invention relates more particularly to the construction of life saving
mattresses, buoys, beacons, and the like, but is also applicable to analogous
structures. The said improvements consist in the combination with the shells of
such structures, of a buoyant filling of lamp-black to increase their buoyancy, and
render them water repellant, as hereinafter described.
In the accompanying Drawing,-
Figure 1 is a plan of a life saving-mattress constructed according to this
Invention, and
Figure is a section of the same on the line x, x, Figure 1.
Figure 3 represents a buoy, and
Figure 4 a life preserver also constructed according to the said Invention. A
represents the enclosing case, shell, or sack, and B the filling of lamp-black.
In life preservers I use a case or structure of painted canvas or other suitable
material of a nature that will prevent the fine powder or lamp-black from sifting
through; and in buoys, beacons, and ships' compartments, I prefer the ordinary
construction and material; but in filling the shell, sack, or casing, I find it
necessary to compact the filling of lamp-black to a certain density only; the exact
degree cannot be given with reference to different circumstances, but the filling
should be compacted to a mean density, sufficient only to obtain the highest degree
of buoyancy, for if compacted to a density beyond such mean, the buoyant
properties of the filling would be lost, and it would become highly ponderable.

page_text: I use the lamp-black because of its marked and super-imponderability, and
because of its incapacity to being assimilated with water under ordinary circum-
stances to form a solid.
Should accident cause a hole in the mattress or collision effect a perforation in a
buoy, the impenetrable powder of lamp-black will act as a barrier to the inroads of
water. I use it also because it is the cheapest known solid of the least specific
gravity, and because it is an article of commerce requiring no preparation for use.
I prefer to employ lamp-black made from resinous substances as giving the least
specific gravity of ordinary productions. For the purpose stated it must be used
under a certain condition of compactness to obtain the best floating results; for if
used under too great a degree of density it fails of its proper function, beyond a
certain density its specific gravity increases, and would correspondingly defeat the
object aimed at, while if used without a due degree of compactness, its bulk would
materially depreciate its advantageous uses for the purpose stated. It is a material
matter therefore that it be used with a degree of compactness that will give it the
greatest active buoyancy in the least possible space without regard to the weight
to be sustained. In filling a form or structure, care must be taken in obtaining
the required density that the filling be gradual and under a gradual pressure,
otherwise the material will be displaced on account of its extreme lightness.
As a repellant for water and moisture, lamp-black is pre-eminently the best
material, therefore if the shell or structure or a compartment thereof within which
it is contained should be punctured or otherwise damaged, it not only precludes the
entrance of water by its repelling property, but also by reason of its compactness
and antagonism to water.
In the application of lamp-black as a buoyant filling, any of the known appliances
or structures of different forms and sizes may be used. For life-boats I propose to
improve the security by filling the usual air tanks or spaces, sectionally by placing
the lamp-black in small sacks or bags, and thereby giving security against all loss
of buoyancy in the event of casualty or damage to the boat, or to any portion
thereof.
In practice it has been found that about one pound of lamp-black is equal to
about three pounds of cork, and that it will have a floating capacity about equal to
six pounds above water, while the use of lamp-black gives infinitely greater
security than air, and its use as a buoyant agent is better than any other known
material.
Having thus fully described the said Invention as communicated to me by my
foreign correspondents, and the manner of performning the same, I wish it under-
stood that I am aware of lamp-black having been used heretofore as a packing, but
as a mere packing it would be useless for the purpose of this Invention; I therefore
do not claim broadly the employment of lamp-black for packing purposes, but I
claim,―
First. A floating structure rendered securely buoyant by means of one or more
chambers filled with lamp-black operating as a water repellant substance, substan-
tially as above described.
Second. In floating bodies, such as life preservers, mattresses, and the like, the
combination of a painted canvas case or structure with a water-repellant filling of
lamp-black, substantially as and for the purpose herein set forth.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Fourth day of May, in the year of our Lord One
thousand eight hundred and eighty.