A METHOD, ENTIRELY NEW AND NOT HITHERTO PRACTICED, OF MAKING OR MANUFACTURING OF RED TRANSPARENT GLASS, WHICH WOULD BE OF GENERAL UTILITY
Year: 1755

page_text: OPPENHEIM the eldest, of the City of London, Merchant, send grecting.
WHEREAS I, the said Mayer Oppenheim, did, by my Petition, humbly
represent unto His most Excellent Majesty King George the Second, that I
had, with great labour, industry, application, and at a considerable expence,
invented and brought to perfection "A METHOD, ENTIRELY NEW AND NOT
HITHERTO PRACTICED, OF MAKING OR MANUFACTURING OF RED TRANSPARENT
GLASS, WHICH WOULD BE OF GENERAL UTILITY," I therefore, by my said Peti-
tion, most humbly prayed His Majesty to grant unto me, the said Mayer
Oppenheim, my executors, administrators, and assigns, especial lycence for the
sole making and vending my said Invention for the term of fourteen years,
according to the Statute in that case made and provided; His said Majesty,
being willing to give encouragement to all arts and inventions which may be
for the publick good, did graciously vouchsafe to condiscend to my request,
and did therefore, by His Letters Patent under the Great Seal of Great
Britain, bearing date at Westminster, the Twenty-eighth day of November, in
the twenty-ninth year of His reign, give and grant unto me, the said Mayer
Oppenheim, His especial licence that I, the said Mayer Oppenheim, my
executors, administrators, and assigns, should and lawfully might make, use,
exercise, and vend my said Invention within that part of Great Britain called
England, His Dominion of Wales, and Town of Berwick-upon-Tweed, for
and during and unto the full end and term of fourteen years from the date of
the said Letters Patent, in such manner as to me, the said Mayer Oppenheim,

page_text: my executors, adñiors, and assigns, should seem meet; in which said Letters
Patent is contained a provisoe that if I, the said Mayer Oppenheim, did
not within four kalendar months next after the date of the said Letters Patent
cause a particular description of the nature of my said Invention, and in what
manner the same was to be performed, by an instrument in writing under my
hand and seal, to be inrolled in His said Majesty's High Court of Chancery,
that then the said Letters Patent, and all liberties & priviledges thereby
granted, should cease, determine, and become void, as in and by the said in
part recited Letters Patent (referrence being thereunto had) may more fully
and at large appear.
NOW KNOW YE, that I, the said Mayer Oppenheim, in pursuance of the
said proviso, do hereby describe the nature of my said Invention, and the
manner in which the same is to be performed, as follows (to wit) :-
:-
Take of the materials that compound the flint glass; let them be well
purified, and to them add an equal quantity of braun stein; mix them
together, and place them in a reverberatory furnace for thirty-six hours. By
that time the calcination will be compleated. This calcination must be
cohobated with warm water until no saline particles remain, when it may be
dry'd, and an equal quantity of sal ammoniac put to it; then levigate well
together by the help of distill'd vinegar; again let it be dried, and put in a
retort well secured; place it in a sand furnace, and give it eighteen hours' fire,
strong enough for sublimation. After this, seperate the calx from the sublimed
matter. To this sublimat let an equal quantity of sal ammoniac be added;
then levigate in the manner before directed, return this mixture into a retort,
and give it a sufficient fire to convert your braun stein to a liquid. Of this
liquid take half an ounce, and to it add thirty grains of dissolved Dutch gold;
put this quantity to every pound of the flint materials; place it in a reverbe-
ratory furnace, and you will have white flint glass, which, on being exposed to
a second heat, will be the red transparent. N.B. The compounds of the flint
contain two parts of lead, one part sand, and one part of saltpetre or borax.
In witness whereof, I, the said Mayer Oppenheim, have hereunto set my
hand and seal, this Fifth day of December, in the said twenty-ninth
year of the reign of His said Majesty King George the Second, and
in the year of our Lord One thousand seven hundred and fifty-five.
MAYER OPPENHEIM, ELDEST. (L.S.)
Sealed and delivered (being first duly
stampt) in the presence of
JOHN MOORE.

page_text: AND BE IT REMEMBRED, that on the said Fifth day of December, in
the year above written, the aforesaid Mayer Oppenheim came before our said
Lord the King in His Chancery, and acknowledged the Writing aforesaid,
and every matter and thing therein contained and specified, in form above said.
And the said Writing was stampt according to the Statute made in the sixth
year of the reign of the late King William and Queen Mary, and so forth.
Inrolled the Twelfth day of March, in the twenty-ninth year of the
reign of His Majesty King George the Second, 1756.