IMPROVEMENTS IN THE MODE OF PRESERVING AND PROTECTING THE SILVERING OF MIRRORS
Year: 1863

page_text: LETTERS PATENT to Marc Antoine François Mennons, of the Firm of
Mennons & Telescheff, Home and Foreign Patent Agents, of Abingdon
Chambers in the City of Westminster, and 24, Rue de Dunkerque, Paris,
in the Empire of France, for the Invention of "IMPROVEMENTS IN THE
MODE OF PRESERVING AND PROTECTING THE SILVERING OF MIRRORS."—A
communication from Diodor Briansky, late Captain in the Russian Army,
residing at No. 16, Malaïa Morskaïa: St. Petersburg...
Sealed the 17th December 1863, and dated the 10th July 1868.
PROVISIONAL SPECIFICATION left by the said .Marc Antoine François
Mennons at the Office of the Commissioners of Patents, with his
Petition, on the 10th July 1868.
I, MARC ANTOINE FRANÇOIS MENNONS, of the Firm of Mennons & Telescheff,
Home and Foreign Patent Agents, of Abingdon Chambers, in the City of
Westminster, and 24, Rue de Dunkerque, Paris, in the Empire of France, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN THE
MODE OF PRESERVING AND PROTECTING THE SILVERING OF MIRRORS," to be as
follows:-
This Invention consists in the application to the silvered surfaces of mirrors
of an adherent elastic coating as a means of preserving the said surfaces from
the destructive effects of shocks, friction, moisture, and other causes of
deterioration to which they may be exposed.

page_text: from 70° to 75° Fahrenheit. In this operation the silvering is freed by the
naphtha of the solution from all fatty and other impurities, and is at same time
strengthened by the caoutchouc which in penetrating into its pores forms the
foundation of the subsequent coatings. On the other hand the unsized paper
absorbs the oily substances taken up by or contained in the naphtha, and
thus prevents the formation of grease spots on the glass.
2d Operation. The surface-prepared as above is covered with a thin but
uniform coating of the solution No. 2, and the glass is left to repose for two
or three days. If necessary the desiccation may be accelerated by increasing
the temperature of the chamber to 100° Fahrenheit.
3d Operation.―The second coat being dried as above is covered with the
mixture No. 3, and the mirror is again left to repose during one or two days,
according to the temperature.
4th Operation. This final process consists in the application of the com-
position No. 4 in successive layers, repeated according to the degree of
thickness and resistance required. The last coating being firmly set the mirror
is ready for use in an e
TO
By the mode of treatment above described the following advantages are
realised t
1stlý, protection of the silvered surface against the action of moisture,
and this so efficiently that the mirror may be stored in damp cellars, or
even kept under water without risk of alteration.
2dly, protection from injury by shocks, friction, or contact with foreign
bodies, and other accidents, and consequent facility of storage, carriage, and
general handling.
3dly, protection from-deterioration by the action of sulphurous and other
vapours, and in fact from all atmospheric influences.
Athly.absolute suppression of mercurial vapoure in annostmonter
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Marc Antoine François Mennons in the Great Seal Patent
Office on the 5th January 1864.
at 20.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, MARC
ANTOINE FRANÇOIS MENNONS, of the Firm of Mennons and Telescheff, Home
and Foreign Patent Agents, of Abingdon Chambers, in the City of Westminster,
and 24, Rue de Dunkerque, Paris, in the Empire of France, send greeting. :

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Tenth day of July, in the year of our Lord
One thousand eight hundred and sixty-three, in the twenty-seventh year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Marc Antoine François Mennons, Her special licence that I,
the said Marc Antoine François Mennons, my executors, administrators, and
assigns, or such others as I, the said Marc Antoine François Mennons, 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 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 THE MODE OF PRESERVING
AND PROTECTING THE SILVERING OF MIRRORS," (a communication from Diodor
Briansky (late Captain in the Russian Army,) a person resident at No. 16,
Malaïa Morskaïa, St. Petersburg, upon the condition (amongst others) that
I, the said Marc Antoine François Mennons, my executors or administrators,
by an instrument in writing under my, or their, or one of their hands and
seals, should particularly describe and ascertain the nature of the said Inven-
tion, 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 Marc Antoine François Mennons, do
hereby declare the nature of the 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 :-
This Invention consists in the application to the silvered surfaces of mirrors
of an adherent elastic coating as a means of preserving the said surfaces from
the destructive effects of shocks, friction, moisture, and other causes of
deterioration to which they may be exposed.
The preparations employed in the execution of the coating processes are as
follows:-
No. 1. Caoutchouc
Naphtha
No. 2.-Caoutchouc
Naphtha -
-
Three pounds
->
- 3 dissolved in
"
Seven pounds
-
7#
Three pounds
- 3 dissolved in
Five pounds
5
To this solution, heated to ebullition, is added by small portions,
Benzine -
Two pounds
After which the mixture is left to coul.
-
2f

page_text: The object of this addition of benzine is to neutralise the effects of the
fatty bodies contained in the naphtha..
No. 3. This preparation is composed of an oil varnish, with which is
incorporated a quantity of minium, zinc white, or other metallic
pigment. The mixture being thoroughly ground up, is brought
to the requisite degree of fluidity by the addition of four parts
of essence of turpentine, and one part of the caoutchouc
solution No. 1.
No. 4. Linseed oil
One and a half pounds
11#
One and a quarter pounds - 1#
One and a quarter pounds -1#
One and a half pounds
->
Essence of turpentine
One and a half pounds
•
#
14
Tallow
-
-
Zinc white
Minium
Binoxide of iron
=
1#
Slaked lime
Portland cement
Bees' wax
Gutta Percha
One quarter pound
-
One quarter pound
Sulphate of lead
Three quarters of a pound
Three quarters of a pound
One half pound
One quarter pound
*#
..
秘
#
t#
These ingredients being ground up are heated together until the volume of
the mass is reduced by about one-fifteenth.
.
The product of this operation being cooled, is again ground up, and reduced
by essence of turpentine to the consistence of syrup.
Moņus OPERANDI.
1st Operation. The mirror being placed on a suitable table its silvered
surface is coated with the solution No. 1, over which are applied sheets of
unsized paper, care being taken to render their adhesion as, complete as
possible. After reposing for from ten to twenty hours the paper is, removed,
carrying with it the most of the adhesive coating, and the silvered surface is
carefully cleaned, after which the mirror is laid aside in a chamber heated to
from 70° to 75° Fahrenheit. In this operation the silvering is freed by the
naphtha of the solution from all fatty and other impurities, and is at same
time strengthened by the caoutchouc, which, in penetrating into its pores,
forms the foundation of the subsequent coatings. On the other hand, the
unsized paper absorbs the oily substances taken up by or contained in the
naphtha, and thus prevents the formation of grease spots on the glass.
2d Operation. The surface prepared as above is covered with a thin but
uniform coating of the solution No. 2, and the glass is left to repose for two

page_text: or three days. If necessary the desiccation may be accelerated by increasing
the temperature of the chamber to 100° Fahrenheit:
3d Operation. The second coat being dried as above is covered with the
mixture No. 3, and the mirror is again left to repose during one or two days,
according to the temperature.
4th Operation. This final process consists in the application of the
composition No. 4 in successive layers, repeated according to the degree of
thickness and resistance required. The last coating being firmly set the
mirror is ready for use.
By the mode of treatment above described the following advantages are
realised:-
1stly, protection of the silvered surface against the action of moisture, and
this so efficiently that the mirror may be stored in damp cellars, or even kept
under water without risk of alteration.
2dly, protection from injury by shocks, friction, or contact with foreign
bodies, and other accidents, and consequent facility of storage, carriage, and
general handling.
3rdly, protection from deterioration by the action of sulphurous and other
vapours, and in fact from all atmospheric influences.
4thly, absolute suppression of mercurial vapours in appartments.
Having now described the nature of the said improvements, and the
manner of carrying them into effect, I would have it understood that I do not
confine myself to the precise details of preparation above laid down, as these
may obviously be modified without deviating from the principle or characteristic
features of this Invention; but what I claim and desire to secure by Letters
Patent is, the application in successive layers to the silvered surfaces of
mirrors, in manner and for the purpose substantially as herein set forth, of
plastic protective compounds combining, like those above enumerated, the
essential qualities of elasticity, tenacity, impermeability, insolubility, and
adhesiveness.
In witness whereof, I, the said Marc Antoine François Mennons, have
hereto set my hand and seal, this Fourth day of January, in the year
of our Lord One thousand eight hundred and sixty-four.
ย
M. F. MENNONS. (L.S.)