A CERTAIN COMPOSITION TO BE USED IN THE MANUFACTURE OF ARTICLES COMPOSED OF OR MADE WITH PLASTER OF PARIS, OR OTHER SIMILAR SUBSTANCES
Year: 1858

page_text: LETTERS PATENT to Giovanni Mariano Casentini and James Orme
Barnard, both of Hercules Buildings, Lambeth, in the County of Surrey,
Architectural Modellers and Copartners in Trade, for the Invention of
"A CERTAIN COMPOSITION TO BE USED IN THE MANUFACTURE OF ARTICLES
COMPOSED OF OR MADE WITH PLASTER OF PARIS, OR OTHER SIMILAR SUBSTANCES."
Sealed the 4th March 1859, and dated the 28th October 1858.
PROVISIONAL SPECIFICATION left by the said Giovanni Mariano
Casentini and James Orme Barnard at the Office of the Commissioners
of Patents, with their Petition, on the 28th October 1858.
We, GIOVANNI MARIANO CASENTINI and JAMES ORME BARNARD, both of
Hercules Buildings, Lambeth, in the County of Surrey, Architectural Modellers
and Copartners in Trade, do hereby declare the nature of the said Invention
for "A CERTAIN COMPOSITION TO BE USED IN THE MANUFACTURE OF ARTICLES
COMPOSED OF OR MADE WITH PLASTER OF PARIS AND OTHER SIMILAR SUBSTANCES,"
to be as follows:-
Our Invention consists of a composition to be used in the manufacture of
articles composed of or made with plaster of Paris and similar substances, into
which manufacture it introduces several important improvements. Plaster of
Paris and other similar substances when guaged or mixed (as is ordinarily the
case) with plain water, set or become hard almost immediately upon being so
guaged, and are thereby rendered inapplicable to purposes in which any

page_text: lengthened degree of manipulation is requisite. This mode of guaging or
mixing is also attended with a further disadvantage of rendering the said
substances extremely loose and friable.
Various methods have at different times been proposed of obviating these
inconveniences, among others that of mechanically mixing borax in a dry
state with a calcined gypsum or other calcareous substances, but such last
mentioned method has not, so far as we have been able to ascertain, been
brought successfully into practice. In the manufacture of scagliola, indeed,
the setting or hardening of the substances operated upon has been retarded by
the use of a solution of glue in the water with which such substances have been
guaged or mixed, but the presence of the glue in such solution deadens the
effect of the colors employed, and renders the scagliola laid upon walls in a
damp or imperfectly dry state very liable to decomposition. By the use of
the composition invented by us all the above inconveniences are entirely
obviated.
A further improvement is introduced into the said manufacture by
immersing in a solution of the said composition articles made in the ordinary
way from plaster of Paris or other similar substances, whereby they become in
a very high degree compact and hard; the same effect, it may be observed, will
be produced upon articles formed of clay or porous stone by similar treatment.
We prepare the composition as follows:-We pour into an iron or other
suitable vessel a sufficient quantity of water for the purpose herein-after men-
tioned, and add to it a certain quantity of cream of tartar; we then boil the
said mixture, and throw into it by degrees, while boiling, borax of commerce,
either ground or unground, in the proportion of 1 lb. of borax for each quarter of
an ounce of cream of tartar, and continue the boiling until the amount of liquid
in the said vessel is sufficient to form with the said borax a thickish paste. The
mixture should be stirred while boiling; or the said paste may be prepared
without boiling, in which case the borax must be ground very fine, and left to
steep for a considerable time in a solution of cream of tartar and water, the
proportion of the said ingredients being those herein-before specified.
Having obtained the paste by either of the modes of proceeding herein-
before mentioned, we place the same in a rolling mill or mortar, and roll or
pound the same into a state of uniform consistency and great fineness. The
rolled or pounded paste thus obtained, which we call "hydroboron," will be
found in many respects the most convenient form in which the said com-
position can be kept until required for use; it may, however, be kept in
solution with any amount of water if it be desired to retain it in that condition
until required for use.

page_text: The composition when required for use is dissolved in or mixed with plain
cold water. The quantity of the composition to be dissolved or mixed with
the water, as herein-before mentioned, depends upon the length of time during
which it is desired to retard the setting or hardening of the substances
operated upon, but as the setting or hardening of these substances materially
depends upon their age and quality, and (but with very trifling variations)
upon the atmospheric conditions under which the guaging is conducted, these
proportions may be more easily arrived at by actual experiment than by
implicitly following any rule; but a useful proportion where the plaster or
other substance is of average quality is 1 lb. of the hydroboron herein-before
mentioned to 6 gallons of water.
The plaster of Paris and other similar substances guaged by the solution
herein-before mentioned will when dried be found to be greatly indurated, and
capable of receiving a high degree of polish, while in the manufacture of
scagliola it will be found that the same can be laid upon walls in a damp or
imperfectly dry state, and that the colors used in the said manufacture retain
their appearance in the finished scagliola with undiminished brilliancy.
Having thus described the nature of our said Invention, and the best means
with which we are acquainted of performing the same, we claim for ourselves
and our licencees under the said Letters Patent, the sole right to make, use,
exercise, and vend the composition herein-before specified, whether in the form
of a paste or a solution.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Giovanni Mariano Casentini and James Orme Barnard in
the Great Seal Patent Office on the 18th April 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, GIOVANNI
MARIANO CASENTINI and JAMES ORME BARNARD, both of Hercules Buildings,
Lambeth, in the County of Surrey, Architectural Modellers and Copartners
in Trade, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-eighth day of October, in the year of our Lord
One thousand eight hundred and fifty-eight, in the twenty-second year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
us, the said Giovanni Mariano Casentini and James Orme Barnard, Her special
license that we, the said Giovanni Mariano Casentini and James Orme Bar-
nard, our executors, administrators, and assigns, or such others as we, tho

page_text: said Giovanni Mariano Casentini and James Orme Barnard, our 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 "A CERTAIN COMPOSITION TO BE USED IN THE
MANUFACTURE OF ARTICLES COMPOSED OF OR MADE WITH PLASTER OF PARIS AND
OTHER SIMILAR SUBSTANCES," upon the condition, amongst others, that we, the
said Giovanni Mariano Casentini and James Orme Barnard, by an instru-
ment in writing under our hands and seals, 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 we, the said Giovanni Mariano Casentini and James
Orme Barnard, do hereby declare the nature of our 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]:-
Our Invention consists of a composition to be used in the manufacture of
articles composed of or made with plaster of Paris and similar substances, into
which manufacture it introduces several important improvements. Plaster of
Paris and other similar substancès when guaged or mixed [as is ordinarily the
case] with plain water, set or become hard almost immediately upon being so
guaged, and are thereby rendered inapplicable to purposes in which any
Jengthened degree of manipulation is requisite. This mode of guaging or
mixing is also attended with the further disadvantage of rendering the said
substances extremely loose and friable.
Various methods have at different times been proposed of obviating these
inconveniences, among others that of mechanically mixing borax in a dry
state with calcined gypsum or other calcareous substances, but such last-
mentioned method has not, so far as we have been able to ascertain, becn
brought successfully into practice. In the manufacture of scagliola, indeed,
the setting or hardening of the substances operated upon has been retarded by
the use of a solution of glue in the water with which such substances have been
guaged or mixed, but the presence of the glue in such solution deadens the
effect of the colors employed, and renders the scagliola laid upon walls in a
damp or imperfectly dry state very liable to decomposition. By the use of
the composition invented by us, all the above inconveniences are entirely
obviated.

page_text: A further improvement is introduced into the said manufacture by
immersing in a solution of the said composition articles made in the ordinary
way from plaster of Paris or other similar substances, whereby they become in
a very high degree compact and hard. The same effect, it may be observed,
will be produced upon articles formed of clay or porous stone by similar treat-
ment. We prepare the composition as follows:-We pour into an iron or
other suitable vessel a sufficient quantity of water for the purpose. herein-after
mentioned, and add to it a certain quantity of cream of tartar; we then boil
the said mixture, and throw into it by degrees, while boiling, borax of com-
merce, either ground or unground, in the proportion of one pound of borax for
each quarter of an ounce of cream of tartar, and continue the boiling until the
amount of liquid in the said vessel is sufficient to form with the said borax a
thickish paste. The mixture should be stirred while boiling, or the said paste
may be prepared without boiling, in which case the borax must be ground very
fine, and left to steep for a considerable time in a solution of cream of tartar
and water, the proportion of the said ingredients being those hercin-beforo
specified.
Having obtained the pasto by either of the modes of proceeding herein-
before mentioned, we place the same in a rolling mill or mortar, and roll or
pound the same into a state of uniform consistency and great fineness. The
rolled or pounded paste thus obtained, which we call "hydroboron," will be
found in many respects the most convenient form in which the said composition
can be kept until required for use; it may, however, be kept in solution with
any amount of water if it be desired to retain it in that condition until required
for use.
The composition when required for use is dissolved in or mixed with plain
cold water. The quantity of the composition to be dissolved or mixed with
the water as herein-before mentioned depends upon the length of time during
which it is desired to retard the setting or hardening of the substances operated
upon, but as the setting or hardening of these substances materially depends
upon their age and quality, and [but with very trifling variations] upon the
atmospheric conditions under which the guaging is conducted, these proportions
may be more easily arrived at by actual experiment than by implicitly
following any rule, but a useful proportion, where the plaster or other substance
is of average quality, is one pound of the hydroboron, herein-before mentioned,
to six gallons of water.
The plaster of Paris and other similar substances guaged by the solution
herein-before mentioned will when dry be found to be greatly indurated, and
capable of receiving a high degree of polish, while in the manufacture of

page_text: scagliola it will be found that the same can be laid upon walls in a damp or
imperfectly dry state, and that the colors used in the said manufacture retain
their appearance in the finished scagliola with undiminished brilliancy.
Having thus described the nature of our said Invention, and the best means
with which we are acquainted of performing the same, we claim for ourselves
and our licencees under the said Letters Patent, the sole right to make, use,
exercise, and vend the composition herein-before specified, whether in the
form of a paste or a solution.
In witness whereof, we, the said Giovanni Mariano Casentini and James
Orme Barnard, have hereunto set our hands and seals, this Eighteenth
day of April, in the year of our Lord One thousand eight hundred
and fifty-nine.
G. M. CASENTINI.
(L.B.)
JAS. ORME BARNARD. (L.S.)
G. M. CASENTINI.
(L.B.)
JAS. ORME BARNARD. (L.S.)