A MEANS OF RENDERING POROUS SUBSTANCES WATERPROOF
Year: 1854

page_text: LETTERS PATENT to Damiano Assanti, of Upper Berkeley Street, in the
County of Middlesex, Gentleman, for the Invention of "A MEANS OF
RENDERING POROUS SUBSTANCES WATERPROOF."
Sealed the 8th August 1854, and dated the 22nd February 1854.
PROVISIONAL SPECIFICATION left by the said Damiano Assanti at the
Office of the Commissioners of Patents, with his Petition, on the 22nd
February 1854.
I, DAMIANO ASSANTI, of Upper Berkeley Street, in the County of Middlesex,
Gentleman, do hereby declare the nature of the said Invention for "A MEANS
OF RENDERING POROUS SUBSTANCES WATERPROOF" to be as follows:-
The Invention consists in rendering porous substances, such as leather,
cloth, earthenware, paper, wood, &c., waterproof, by causing them to imbibe or
absorb gutta percha.
I dissolve the gutta percha in sulphuret of carbon or other solvent, and
plunge the objects to be made waterproof therein. The gutta percha will thus
enter into the pores of the substance, while the dissolving agent will evaporate
and leave the substance so treated waterproof.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Damiano Assanti in the Great Seal Patent Office on the
22nd August 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, DAMIANO
ASSANTI, of Upper Berkeley Street, in the County of Middlesex, Gentleman,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent bearing date the Twenty-second day of February, 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 Damiano Assanti, Her special licence, that I, the said Damiano
Assanti, my executors, administrators, and assigns, or such others as I, the
said Damiano Assanti, 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, exer-
cise, and vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "A MEANS OF RENDERING
POROUS SUBSTANCES WATERPROOF," upon the condition (amongst others) that I,
the said Damiano Assanti, 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 Damiano Assanti, do hereby declare
the nature of my 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:-
The Invention consists in rendering porous substances, such as leather, cloth,
earthenware, paper, &c., waterproof, by causing them to imbibe or absorb gutta
percha.
I dissolve the gutta percha in sulphuret of carbon or other solvent, and
plunge the objects to be made waterproof therein. The gutta percha will thus
enter into the pores of the substance, while the dissolving agent will evaporate,
and leave the substance so treated waterproof and at the same time more
compact and more durable.
I prefer sulphuret of carbon as the dissolving agent, on account of its being
cheaper than any other, because it volatilizes easier at a low heat, and con-
denses readily on lowering the temperature. Ï prepare my solution thus:-

page_text: I take one part by weight of dry gutta percha cut up into small pieces, and
add four parts of sulphuret of carbon; I keep this mixture at a temperature
of about 77° Fahrenheit, and agitate it at least six times in twenty-four hours.
In two days the solution will be ready for use.
The solution is placed in any suitable closed vessel which will admit of being
heated in a water bath, and of the evaporation and condensation of the
sulphuret of carbon taking place. I wet down the goods to be waterproofed
in this vessel, and cause the solution to cover them entirely; 'I then place the
vessel in a water bath and heat it for five hours, without, however, carrying the
temperature to the boiling point. When the temperature of the bath has fallen
to about 85° Fahrenheit, I remove the goods, allow them to drain, and place them
in another vessel, which is again heated in a water bath; in order to evaporate
and condense the remainder of the sulphuret of carbon. The goods are after-
wards removed from this vessel, are then dried or allowed to dry, and are
submitted to pressure or not according to their nature.
If the substances to be saturated are too compact to absorb the solution by
simple immersion, such, for instance, as blocks of wood, it is necessary to force
it in by exhausting the air from the wood, and by pressure applied on. the
surface of the solution, as is done in the preservation of timber.
And having now described the nature of the said Invention, and in what
manner the same is to be performed, I declare that I claim, the rendering of
porous substances and goods waterproof, by causing them to imbibe a solution
of gutta percha or other similar substance, by the means and in the manner
herein-before described.
In witness whereof, I, the said Damiano Assanti, have hereunto set my
hand and seal, this Twenty-first day of August, One thousand eight
hundred and fifty-four.
DAMIANO ASSANTI. (L.S.)