IMPROVEMENTS IN THE MANUFACTURE OF WATERPROOF FABRICS AND OF WATERPROOF BAGS AND OTHER ARTICLES
Year: 1854

page_text: LETTERS PATENT to David Blair White, of Newcastle-upon-Tyne, Doctor
of Medicine, for the Invention of "IMPROVEMENTS IN THE MANUFACTURE OF
Sealed the 30th June 1854, and dated the 5th January 1854.
PROVISIONAL SPECIFICATION left by the said David Blair White at
the Office of the Commissioners of Patents, with his Petition, on the
5th January 1854.
I, DAVID BLAIR WHITE, of Newcastle-upon-Tyne, Doctor of Medicine, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN THE
MANUFACTURE OF WATERPROOF FABRICS AND OF WATERPROOF BAGS AND OTHER
ARTICLES" to be as follows:-
My Invention has reference to the rendering waterproof canvas and other
like materials, for any purpose to which it may be applied, but more especially
for the manufacture of waterproof bags for containing liquids. And my said
Invention consists in the production in or upon the material (whether made up
into bags or not) of a soap or compound which is insoluble in water, by the
use of resin dissolved in coal tar oil, or other suitable solvent, and of a
metallic oxide, or of an alkaline earth, or of both a metallic oxide and an
alkaline earth, and either with or without the addition to the resin solution of
pitch, or a solution of indian-rubber in naptha, or in other suitable solvent,

page_text: or of pitch and indian-rubber solution. It is however to be distinctly under-
stood, that by the term "solution," as here used, I do not limit my Invention
to the use of the materials mentioned actually dissolved, as I reserve to myself
the right of making either separate or combined applications of the materials
and the solvents. And I further reserve to myself the right of either separate
or combined applications of the solutions.
The best manner I have yet been able to ascertain of performing my said
invention is by the use of the following proportions and quality of the ma-
terials, and by the following method of proceeding; that is to say, I prefer the
common dark resin of commerce, of which I make a solution in the coal tar
oil, in the proportion of about two pounds of resin to five gallons of the oil;
and when I make use of pitch and indian-rubber solution, I add thereto about
one pound eight ounces of the pitch and four ounces of the indian-rubber,
and I steep the canvas or material for about five days in this solution; after
which, when it is removed from the solution and while it remains still damp, I
rub into or upon it either oxides of lead, or oxychloride of lead, or else com-
mon lime, or else both oxide and alkali, either of such applications having the
effect of forming a compound with the previous solution, or application, which
is insoluble in water, and having also the property of drying quickly. When
dry I repeat the operations, only varying the former by the use of a stronger
solution, that is, of about five pounds of the resin to five gallons of the oil;
and while the canvas or material again remains damp I apply the oxide, or
the oxychloride of lead, or the lime, or both the oxide and the alkali, and
allow it to dry.
!
In the manufacture of waterproof bags I first make them up of the canvas
or material, either before or after it has been prepared or partly prepared
as above, and I treat both the inside and the outside of the bags with the last
mentioned strong solution of the resin, and with the oxide or oxychloride of
lead, or the lime, or both the oxide and the alkali, so as to close and stop up
the seams or joinings; and in addition I also prefer to give the bags a coating
of a mixture containing pitch and indian-rubber solution.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said David Blair White in the Great Seal Patent Office on the
4th July 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, DAVID
BLAIR WHITE, of Newcastle-upon-Tyne, Doctor of Medicine, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifth day of January, in the year of our Lord One
thousand eight hundred and fifty-four, in the seventeenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
David Blair White, Her special licence that I, the said David Blair White,
my executors, administrators, and assigns, or such others as I, the said David
Blair White, my executors, administrators, 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 THE MANUFAC-
TURE OF WATERPROOF FABRICS AND OF WATERPROOF BAGS AND OTHER ARTICLES,"
upon the condition (amongst others) that I, the said David Blair White, by
an instrument in writing under my hand and seal, should particularly describe
and ascertain the nature of the 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 David Blair White, 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):-
My Invention has reference to the rendering waterproof canvas and other
like materials for any purpose to which it may be applied, but more especially
for the manufacture of waterproof bags for containing liquids. And my said
Invention consists in the production in or upon the material (whether made up
into bags or not) of a compound which is insoluble in water by the use of
resin dissolved in coal tar oil, or other suitable solvent, and of a metallic oxide
or of an alkaline earth, or of both a metallic oxide and an alkaline earth, and
either with or without the addition (to the resin solution) of pitch, or a solu-
tion of indian-rubber in naptha, or in other suitable solvent, or of pitch and

page_text: indian-rubber solution. It is however to be distinctly understood that by the
term "solution," as here used, I do not limit my Invention to the use of the
materials mentioned actually dissolved, as I reserve to myself the right of
making either separate or combined applications of the materials and the
solvents. And I further reserve to myself the right of either separate or
combined applications of the solutions.
The best manner I have yet been able to ascertain of performing my said
Invention is by the use of the following proportions and quality of the ma-
terials, and by the following method of proceeding (that is to say), I prefer the
common dark resin of commerce, of which I make a solution in the coal tar
oil, in the proportion of about two pounds of resin to five gallons of the oil;
and when I make use of pitch and india-rubber solution I add thereto about
one pound eight ounces of the pitch and four ounces of the indian-rubber.
And I steep the canvas or material for about five days in either of these
solutions. after which, when it is removed from the solution, and while it
remains still damp, I rub into or upon it either oxide of lead, or oxychloride of
lead, or else common lime, or else both the oxide and alkaline earth, either of
such applications having the effect of forming a compound with the previous
solution or application, which is insoluble in water, and having also the
property of drying quickly. When dry I repeat the operations, only varying
the former by the use of a stronger solution, that is, of about five pounds of
the resin to five gallons of the oil, and while the canvas or material remains
damp I again apply the oxide, or the oxychloride of lead, or the lime, or both
the oxide and the alkaline earth, and allow it to dry.
In the manufacture of waterproof bags I first make them up of the canvas
or material, either before or after it has been prepared, or partly prepared as
above, and I treat both the inside and the outside of the bags with the last
mentioned strong solution of the resin, and with the oxide, or oxychloride of
lead, or the lime, or both the oxide and the alkaline earth, so as to close and
stop up the scams or joinings; and in addition I also prefer to give the bags a
coating of a mixture containing pitch and india-rubber solution.
In order still more to ensure the waterproof character of the bags, and at
the same time to render them repellent to the attacks of vermin (to which
they might be liable when used for stowing water ballast or liquid cargo in
ships), and also to make them stronger and less liable to decay, I cover them
externally with a strongly banded canvas covering, which is saturated with
tar oil. And I would remark that for common stowage purposes I wash the
interior of the bags with a strong solution of chloride of lime, or other soluble

page_text: chloride; but when they are intended for cargo stowage I line their interior
with thin sheet gutta percha (as manufactured by the Gutta Percha Company),
this material having been found not to deteriorate or injure the contents by
imparting a flavor to them. Although the exterior lining, the washing
internally, and the interior lining lastly above described, are recommended to
be used, yet having been practised with regard to bags hitherto made, they
constitute no feature in my present Invention.
In witness whereof, I, the said David Blair White, have hereunto set my
hand and seal, this Third day of July, One thousand eight hundred
and fifty-four.
DAVID BLAIR WHITE. (L.S.)