THE MANUFACTURE OF A SOLUTION FOR MIXING WITH OR GUAGING PLASTER OF PARIS (OR ANY PLASTER HAVING SULPHATE OF LIME OR ANY SIMILAR SUBSTANCE FOR ITS BASE), SO AS TO PRODUCE A HARD AND DENSE COMPOSITION, THE HARDENING OR SETTING WHEREOF MAY BE RETARDED AND REGULATED BY THE PERSON USING THE SAME
Year: 1858

page_text: LETTERS PATENT to Giovanni Mariano Casentini, of 24, Hercules Buildings,
Lambeth, in the County of Surrey, Architectural Modeller and Worker
in Scagliola, for the Invention of "THE MANUFACTURE OF A SOLUTION FOR
MIXING WITH OR GUAGING PLASTER OF PARIS (OR ANY PLASTER HAVING
SULPHATE OF LIME OR ANY SIMILAR SUBSTANCE FOR ITS BASE), SO AS TO
PRODUCE A HARD AND DENSE COMPOSITION, THE HARDENING OR SETTING
WHEREOF MAY BE RETARDED AND REGULATED BY THE PERSON USING THE SAME."
Sealed the 16th July 1858, and dated the 19th May 1858.
PROVISIONAL SPECIFICATION left by the said Giovanni Mariano
Casentini at the Office of the Commissioners of Patents, with his
Petition, on the 19th May 1858.
I, GIOVANNI MARIANO CASENTINI, of 24, Hercules Buildings, Lambeth, in
the County of Surrey, Architectural Modeller and Worker in Scagliola, do
hereby declare the nature of the said Invention for "THE MANUFACTURE OF
A SOLUTION FOR MIXING WITH OR GUAGING PLASTER OF PARIS (OR ANY PLASTER
HAVING SULPHATE OF LIME OR ANY SIMILAR SUBSTANCE FOR ITS BASE), SO AS TO
PRODUCE A HARD AND DENSE COMPOSITION, THE HARDENING OR SETTING WHEREOF
MAY BE RETARDED AND REGULATED BY THE PERSON USING THE SAME," to be as
follows:-

page_text: The Invention consists in mixing or guaging plaster of Paris (or any plaster
having sulphate of lime or any similar substance for its base) with a solution
of borax in water instead of with water only. Borax, I believe, has been and
is now used in the manufacture of cement in various forms, but so far as I
am aware, it has never been used in the form of a simple solution to be
mixed with plaster when and as the latter is about to be used.
My Invention or improvement consists in mixing or guaging the plaster at
the time of its use with a solution of borax, of such strength as may be best
adapted for the work to be performed. I make a saturated solution of borax
in water, and when about to use it I dilute this solution with from one to
eight parts of water, as I require the plaster to set or harden less or more
rapidly. By using the solution, the setting or hardening of the plaster is
retarded from fifteen minutes to ten hours, or thereabouts, according to the
strength of the solution used. I also claim the use of this solution in mixing
or preparing plaster for scagliola work, in which the solution does not interfere
with the employment of any colouring matter. In every case the use of the
solution renders the plaster so treated very hard and durable, and capable of
receiving a very high polish.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Giovanni Mariano Casentini in the Great Seal Patent Office 2
on the 11th November 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GIOVANNI
MARIANO CASENTINI, of Hercules Buildings, Lambeth, in the County of
Surrey, Architectural Modeller and Worker in Scagliola, send greeting.
WHEREAS 1er most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Nineteenth day of May, in the year of our Lord One
thousand eight hundred and fifty-eight, in the twenty-first year of Her reign,
did, for Herself, er heirs and successors, give and grant unto me, the said
Giovanni Mariano Casentini, Iler special licence that I, the said Giovanni
Mariano Casentini, my executors, administrators, and assigns, or such others
ns I, the said Giovanni Mariano Casentini, 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
THE MANUFACTURE OF A SOLUTION FOR MIXING WITH OR GUAGING PLASTER OF

page_text: PARIS (OR ANY PLASTER HAVING SULPHATE OF LIME OR ANY SIMILAR SUBSTANCE
FOR ITS BASE), SO AS TO PRODUCE A HARD AND DENSE COMPOSITION, THE HARDENING
OR SETTING WHEREOF MAY BE RETARDED AND REGULATED BY THE PERSON USING THE
SAME," upon the condition (amongst others) that I, the said Giovanni Mariano
Casentini, 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 Giovanni Mariano Casentini, 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 (that is to say) :—
I prepare the said solution in one of the following ways:-I take borax of
commerce, and having ground it very fine, place a certain quantity of it in an
iron or other vessel suitable for the process herein-after described, I then pour
into the said vessel water in the proportion of one and a half gallons for each
pound of borax in the said vessel. The contents of the said vessel are then
boiled, and maintained at the boiling point until by evaporation they are
reduced to a saturated solution of the said borax. The contents of the said
vessel should, during such boiling, be continually stirred. The saturated solu-
tion is then allowed to cool, when it is bottled off, and in that state kept until
it is required for use. Or, instead of grinding the borax, I prepare
the same
by placing unground borax in the same proportion as before into boiling water
in a similar vessel, and maintaining the contents of the said vessel at a boiling
point until, as before, they have been reduced to a saturated solution, the
liquid being during such boiling continually stirred. This mode, however, I
do not recommend except where facilities are wanting for preparing the said
solution in the manner herein-before or herein-after described. Another
mole consists in placing the unground borax in cold water, and gradually
boiling the saine until the moisture left with the said borax is sufficient only
to form a thickish paste. This paste I remove from the vessel, and place
either in a rolling mill or in a mortar, and roll or pound the same until the
said paste is very fine and smooth, I then place the said paste in water, and
constantly but very gradually increase the quantity of the said water, so as to
attain after some length of time in boiling the condition of a saturated solu-
tion, which, as before, is bottled off and kept until required for use. And
this third method I would state is the one I should recommend in all cases in
which there are the facilities for rolling or pounding, as herein specified.

page_text: The mode in which I employ the solution is as follows:-I mix with it a
proportion of water dependent on the period during which I wish to retard
the setting of the substances operated upon. If the proportion of the re-
spective bulks of the solution and water be that of 1 to 12, the bardening is
retarded about fifteen minutes; if that of 1 to 8, thirty minutes; of 1 to 6,
from one and a half hours to three hours; of 1 to 4, from 3 to 5 hours; 1 to
2, from seven to ten hours; and when the solution and water are mixed in
equal parts, from ten to twelve hours. These times are, it should be observed,
liable to slight variations dependent upon the quality and condition of the
materials employed.
In witness whereof, I, the said Giovanni Mariano Casentini, have here-
unto set my hand and seal, this Tenth day of November, in the year
of our Lord One thousand eight hundred and fifty-eight.
J. M. CASENTINI. (L.8.)
Signed and sealed by the above-named
Giovanni Mariano Casentini, in the
presence of
J. BARNARD, Sol.
14, York Road, Lambeth.