IMPROVEMENTS IN PRODUCING GRADUATED SCALES AND OTHER SIGNS, LETTERS, NUMERALS, CHARACTERS, AND PICTORIAL REPRESENTATIONS UPON PORCELAIN AND OTHER CERAMIC AND ENAMELLED MATERIALS, WHICH IMPROVEMENTS ARE APPLICABLE TO THE GRADUATED SCALES OF METEOROLOGICAL AND OTHER PHILOSOPHICAL INSTRUMENTS
Year: 1857

page_text: LETTERS PATENT to Henry Angelo Ludovico Negretti and Joseph Warren
Zambra, of Hatton Garden, in the County of Middlesex, Opticians and
Meteorological Instrument Makers, for the Invention of "IMPROVEMENTS
IN PRODUCING GRADUATED SCALES AND OTHER SIGNS, LETTERS, NUMERALS,
CHARACTERS, AND PICTORIAL REPRESENTATIONS UPON PORCELAIN AND OTHER
CERAMIC AND ENAMELLED MATERIALS, WHICH IMPROVEMENTS ARE APPLICABLE
TO THE GRADUATED SCALES OF METEOROLOGICAL AND OTHER PHILOSOPHICAL
INSTRUMENTS."
Sealed the 13th April 1858, and dated the 15th October 1857.
PROVISIONAL SPECIFICATION left by the said Henry Angelo Ludovico.
Negretti and Joseph Warren Zambra at the Office of the Commis-
sioners of Patents, with their Petition, on the 15th October 1857.
We, HENRY ANGELO LUDOVICO NEGRETTI and JOSEPH WARREN ZAMBRA, of
5 Hatton Garden, in the County of Middlesex, Opticians and Meteorological'
Instrument Makers, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN PRODUCING GRADUATED SCALES, AND OTHER SIGNS, LETTERS,

page_text: NUMERALS, CHARACTERS, AND PICTORIAL REPRESENTATIONS UPON PORCELAIN AND
OTHER CERAMIC AND ENAMELLED MATERIALS; WHICH IMPROVEMENTS ARE APPLICABLE
TO THE GRADUATED SCALES OF METEOROLOGICAL AND OTHER PHILOSOPHICAL INSTRU-
MENTS," to be as follows:-
These Improvements consists in this:-Instead of painting or printing the
required graduated scales, and other signs, letters, &c., and then baking the
substance, which is afterwards enamelled and again baked, we take the
substances already enamelled in the form and shape required so as to be ready
for use, & we produce the graduated scales and other signs, letters, &c. by
etching in similar manner as practised in etching upon glass (the production
of graduated and other signs, &c. upon glass proper not belonging to this
Invention) that is, with hydrofluoric acid or fluoric acid gas.
The above is a description of the nature of the said Invention, which may
however, as regards the details, be varied in practice.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Henry Angelo Ludovico Negretti and Joseph Warren
Zambra in the Great Seal Patent Office on the 15th April 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, HENRY
ANGELO LUDOVICO NEGRETTI and JOSEPH WARREN ZAMBRA, of Hatton Garden,
in the County of Middlesex, Opticians and Meteorological Instrument, Manu-
facturers, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by, Her Letters
Patent, bearing date the Fifteenth day of October, in the year of our Lord
One thousand eight hundred and fifty-seven, in the twenty-first year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto us,
the said Henry Angelo Ludovico Negretti and Joseph Warren Zambra, Her
special licence that we, the said Henry Angelo Ludovico Negretti and Joseph
Warren Zambra, our executors, administrators, and assigns, or such others
as we, the said Henry Angelo Ludovico Negretti and Joseph Warren Zambra,
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, "IMPROVEMENTS, IN PRO-
DUCING GRADUATED SCALES, AND OTHER SIGNS, LETTERS, NUMERALS, CHARACTERS,
c
71444
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page_text: AND PICTORIAL REPRESENTATIONS. UPON PORCELAIN. AND OTHER. CERAMIC AND
ENAMELLED MATERIALS, WHICH IMPROVEMENTS ARE APPLICABLE TO THE. GRADUATED
SCALES OF METEOROLOGICAL AND OTHER PHILOSOPHICAL INSTRUMENTS," upon the con-
dition (amongst others), that we, the said Henry Angelo Ludovico Negretti and
Joseph Warren Zambra, our executors or administrators, by an instrument
in writing under our, or their, or one of their hands and seals, should par-
ticularly 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 imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that we, the said Henry Angelo Ludovico Negretti
and Joseph Warren Zambra, do hereby declare the nature of our sail
Invention, and in what manner the same is to be performed, to be par-
ticularly described, and. ascertained, in and. by the following statement:-.
The said Invention consists in producing degrees, numerals, characters,
signs, letters, or figures for the scales of meteorological and philosophical
instruments, such as are usually painted, printed, or engraved for the scales of
such instruments, and when made of porcelain or other ceramic ware, have
been heretofore first painted or printed, and then baked according to the
known processes adopted by porcelain manufacturers, thereby producing on
the porcelain or other ceramic material, figures, letters, characters, and the
like, the same being afterwards glazed and again baked.
Instead of adopting any such processes, we take the porcelain, or other
ceramic or enamelled material, either in the biscuit or other state, and in
the form or state required so as to be ready for use, and we produce the
graduated scales and other signs, characters, letters, or delineations required
by etching alone, in similar manner as practised in etching upon glass (the
production of graduated signs, letters, and such like upon glass proper not
forming any part or portion of this Invention). And this we effect by the
use of hydrofluoric or fluoric acid gas, applying or using the same in the
ordinary way of etching. Instead of making the slabs or pieces on which the
scales, &c. are to be produced wholly of porcelain or other ceramic material,
it may be desirable in some cases to use a slab or piece of metal or other
suitable material, coated or enamelled with porcelain, and in this case the
process will still remain the same.
Having now described the nature of the said Invention, and in what
manner the same is to be performed, we declare that we claim the production
of graduated scales, and other signs, letters, numerals, characters, and repre-

page_text: sentations upon porcelain, and ceramic and enamelled materials, by etching
the same in the manner herein-before described.
In witness whereof, the said Henry Angelo Ludovico Negretti and
Joseph Warren Zambra, have hereunto set our hands and seals, this
Fourteenth day of April, One thousand eight hundred and fifty-eight.
H'. NEGRETTI.
(L.S.)
Signed and sealed in my presence,
F. W. CAMPIN, Patent Agent,
156, Strand.
J. W. ZAMBRA. (L.S.)