IMPROVEMENTS IN THE MANUFACTURE OF USEFUL AND ORNAMENTAL ARTICLES, SURFACES, AND WORKS, PARTS OF ARTICLES, AND PARTS OF MACHINERY OR APPARATUS, FROM TALC AND OTHER SILICATES OF MAGNESIA, AND FROM THE SAME COMBINED WITH OTHER SUBSTANCES
Year: 1859

page_text: LETTERS PATENT to Sigismond Leoni, of Saint Paul Street, in the County
of Middlesex, Manufacturer, for the Invention of "IMPROVEMENTS IN THE
MANUFACTURE OF USEFUL AND ORNAMENTAL ARTICLES, SURFACES, AND WORKS,
PARTS OF ARTICLES, AND PARTS OF MACHINERY OR APPARATUS, FROM TALC AND
OTHER SILICATES OF MAGNESIA, AND FROM THE SAME COMBINED WITH OTHER
SUBSTANCES."
Sealed the 15th September 1859, and dated the 21st March 1859.
PROVISIONAL SPECIFICATION left by the said Sigismond Leoni at the
Office of the Commissioners of Patents, with his Petition, on the
21st March 1859.
I, SIGISMOND LEONI, of Saint Paul Street, in the County of Middlesex,
Manufacturer, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN THE MANUFACTURE OF USEFUL AND ORNAMENTAL ARTICLES,
SURFACES, AND WORKS, PARTS OF ARTICLES, AND PARTS OF MACHINERY OR APPA-
RATUS, FROM TALC AND OTHER SILICATES OF MAGNESIA, AND FROM THE SAME COM-
.BINED WITH OTHER SUBSTANCES," to be as follows:-
According to this Invention, tale, steatite, or other silicate of magnesia is
reduced to powder, and either with or without the addition of glass, felspar, lime,
or alumina is pressed or forced in a more or less moist or partially or wholly
plastic state into moulds of the desired form or configuration, and after being
removed from the moulds is baked, burnt, or fired to the requisite hardness.
Metallic salts or oxydes, carbon, or other coloring agent may be employed, if
desired, for imparting color, or for staining.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Sigismond Leoni in the Great Seal Patent Office on the
21st September 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, SIGISMOND
LEONI, of Saint Paul Street, in the County of Middlesex, Manufacturer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-first day of March, in the year of our Lord
One thousand eight hundred and fifty-nine, in the twenty-second year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Sigismond Leoni, Her special licence that. I, the said Sigismond
Leoni, my executors, administrators, and assigns, or such others as I, the
said Sigismond Leoni, 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
mako, use, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for "IM-
PROVEMENTS IN THE MANUFACTURE OF USEFUL AND ORNAMENTAL ARTICLES,
SURFACES, AND WORKS, PARTS OF ARTICLES, AND PARTS OF MACHINERY OR,
APPARATUS, FROM TALC AND OTHER SILICATES OF MAGNESIA, AND PROM THE SAME
COMBINED WITH OTHER SUBSTANCES," upon the condition (amongst others) that
I, the said Sigismond Leoni, my executors or administrators, by an instru-
ment in writing. under my, or their, or one of their 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 I, the said Sigismond Leoni, do hereby declare
the nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say :-
This Invention relates to the manufacture of useful and ornamental articles,
surfaces, and works, parts of articles, and parts of machinery or apparatus,
from talc and other silicates of magnesia, alone or combined with other
substances. For this purpose, according to my Invention, the tale, steatite,
or other silicate of magnesia is first reduced to powder, and either alone or
with the addition of glass, felspar, lime, or alumina is pressed or forced in a
more or less moist or wholly or partially plastic state into moulds of the

page_text: desired form or configuration, and after being removed from the moulds, is
baked, burnt, or fired to the requisite hardness. Metallic salts or oxides,
carbon, or other coloring agent may be employed, if desired, for imparting
color, or for staining. Even in those instances, however, in which I combine
with the tale or other silicate of magnesia, glass, lime, felspar, or alumina, I
employ only a small proportion of these four last-named substances, so that
the silicate of magnesia may be said in all cases to form the main staple of the
material treated according to these my present improvements.
In carrying my Invention into effect, the coloring or staining agents' which
I use are, by preference, similar to those employed for coloring or staining
porcelain, and may be applied by mixing them with the material before pressing
it in the moulds, or otherwise, as desirable; or of course, when preferred,
coloring and staining agents may be wholly dispensed with, and the material
allowed to retain its original hue. For the baking, burning, or firing, the
kilns I use are similar to those adopted by porcelain manufacturers, and
articles manufactured according to my Invention may be enamelled, glazed, or
polished by the means ordinarily employed for such purpose in respect of
porcelain ware.
My Invention is applicable to the manufacture of knife handles, spindle
steps, bearings, toilette furniture, decorative mouldings, and various other
articles, surfaces, and works, and parts of articles, and parts of machinery or
apparatus, in which strength, hardness, and durability, and resistance to heat,
friction, corrosion, or oxydation, &c., &c., are desirable qualities.
And having now described the nature of the said Invention, and in what
manner the same is to be performed, I declaro that what I claim is, manu-
facturing articles, surfaces, and works, parts of articles, and parts of machinery
or apparatus, from talc or other silicates of magnesia, alone or combined with
other substances, in the manner herein-before described.
In witness whereof, I, the said Sigismond Leoni, have hereunto set my
hand and seal, this Nineteenth day of September, in the year of our
Lord One thousand eight hundred and fifty-nine.
Witness,
M. HENRY, Patent Agent,
84, Fleet Street, London.
S. LEONI. (L.S.)