AN IMPROVED MANUFACTURE OF SPE- CULUMS FOR VARIOUS PURPOSES
Year: 1847

page_text: FLETCHER, of Birmingham, Brass Founder, send greeting.
WHEREAS Her present most Gracious Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Third day of August, in the eleventh year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said Theodore
Fletcher, Her especial license that I, the said Theodore Fletcher, my exors,
admors, and assigns, or such others I, the said Theodore Fletcher, my exors,
admors, or assigns, should at any time agree with, and no others, from time
to time and at all times during the term of years therein expressed, should
and lawfully might make, use, exercise, and vend, within England, Wales,
and the Town of Berwick-upon-Tweed, and in Her Islands of Jersey, Guernsey,
Alderney, Sark, and Man, and also in all Her said Majesty's Colonies and
Plantations abroad, my Invention of "AN IMPROVED MANUFACTURE OF SPE-
CULUMS FOR VARIOUS PURPOSES;" in which said Letters Patent is contained a
proviso obliging me, the said Theodore Fletcher, by an instrument in writing
under my
hand and seal, particularly to describe and ascertain the nature of
my said Invention, and in what manner the same is to be performed, and to
cause the same to be enrolled in Her said Majesty's High Court of Chancery
within six calendar months next and immediately after the date of the said
in part recited Letters Patent, as in and by the same, reference being thereunto
had, will more fully and at large appear.

page_text: NOW KNOW YE, that, in compliance with the said proviso, I, the said
Theodore Fletcher, do hereby declare the nature of my said Invention to
consist in coating the backs of glasses which have been quicked or silvered, as
it is called, for the purpose of speculums, such as mirrors, looking glasses, or
reflectors, with metal by means of the process called electro-plating, whereby
great protection from injury is afforded to the quicksilver of the speculums,
and a much stronger power of reflecting light given to the speculum. And in
further compliance with the said proviso, I, the said Theodore Fletcher, do
hereby describe the manner in which my said Invention is to be performed by
the following statement thereof; that is to say:-
I take a glass plate which has been silvered, and lightly and carefully
varnish it over with a varnish composed of shell-lac, spirits of wine, and lamp
black in the following proportions, that is to say, to two ounces of shell-lac
add half a pint of highly rectified spirits of wine and half an ounce of the best
lamp black. This process protects the quicksilver from damp and from the
action of the acids used in the subsequent processes. After the before-
mentioned varnish has been applied, but before it is set hard, and while it is
still what is called tacky, I shake over it from a fine muslin bag either finely-
powdered blacklead, or black oxide of manganeese, or other metallic oxides or
powders, cover it with leaf metal till the whole surface which has been
varnished is perfectly but very thinly covered with metal, and in this state I
submit the glass plate to any of the ordinary electro-plating processes, and
precipitate a thin coating of copper or other metal (but I prefer copper) over
the entire back of the plate, thereby perfectly covering the quicksilver and
protecting it from the effects of damp and accidental friction, which so often
injures looking glasses and mirrors, and renders quicksilvered glasses for
reflectors useless in many instances.
And whereas I claim as my Invention the following improvement in the
manufacture of speculums for looking glasses, mirrors, and reflectors, that is
to say, the subjecting of glass which has been silvered at the back for the
purpose of forming speculums of various kinds to the process of electroplating
on the back, or covering with metal by means of electricity in any of its
various forms arranged for the purpose, one mode of doing which is herein-
before described; and such my Invention being, to the best of my knowledge
and belief, entirely new, and never before used within that part of Her said
Majesty's United Kingdom of Great Britain and Ireland called England, Her
Dominion of Wales, or Town of Berwick-upon-Tweed, or in Her Islands of
Jersey, Guernsey, Alderney, Sark, and Man, nor in any of Her said Majesty's
Colonies or Plantations abroad, I do hereby declare this to be my Specifica-

page_text: tion of the same, and that I do verily believe this my said Specification doth
comply in all respects fully and without reserve or disguise with the proviso in
the said herein-before in part recited Letters Patent contained; wherefore I
hereby claim to maintain exclusive right and privilege to my said Invention.
In witness whereof, I, the said Theodore Fletcher, have hereunto set my
hand and seal, this Eighth day of January, One thousand eight hundred
and forty-eight.