Iм- PROVEMENTS IN THE ELECTRO-DEPOSITION OF TIN, WHICH IMPROVEMENTS ARE APPLICABLE TO THE PREVENTION OF THE OXIDIZATION OR TARNISHING OF SILVER SURFACES AND AS A COATING FOR OTHER METALS."
Year: 1870

page_text: LETTERS PATENT to John Edward Bingham, of Victoria Park, Sheffield,
in the County of York, Manufacturer, for the Invention of “Iм-
PROVEMENTS IN THE ELECTRO-DEPOSITION OF TIN, WHICH IMPROVEMENTS ARE
APPLICABLE TO THE PREVENTION OF THE OXIDIZATION OR TARNISHING OF SILVER
SURFACES AND AS A COATING FOR OTHER METALS."
PROVISIONAL SPECIFICATION left by the said John Edward Bingham
at the Office of the Commissioners of Patents, with his Petition, on
the 28th September 1870.
I, JOHN EDWARD BINGHAM, of Victoria Park, Sheffield, in the County
of York, Manufacturer, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE ELECTRO-DEPOSITION OF TIN, WHICH IMPROVEMENTS
ARE APPLICABLE TO THE PREVENTION OF THE OXIDIZATION OR TARNISHING OF SILVER
SURFACES, AND AS A COATING FOR OTHER METALS," to be as follows:-
In carrying out my Invention of improvements in the electro-deposition
of tin I first take a given quantity of tin, by preference in a pure state,
but what is commercially known and sold as tin may be employed,

page_text: which I dissolve in chlorhydric acid, and precipitate the same by means
of crude potassic hydrate; I then wash the precipitated tin free from
acid, after which I add a quantity of potassie hydrate and also of cyanide
of potassium, and then raise the temperature by preference to a point
just below that at which the solution will boil; this, however, may be
varied, and when the solution has been thus heated I add a quantity
of calcic hydrate. In the solution thus obtained I suspend the sheets
of tin and also the articles to be coated with the same, which will be
previously prepared as is usual when coating articles by the electro-
deposition of metal, and will be understood by persons acquainted with
the electro-deposition of metals. The tin and the articles to be coated
are then connected with the battery in the usual manner, and the
articles to be coated will be retained a greater or less time in the
solution according to the quantity or thickness of tin required to be
deposited on their surface.
I have not given any quantities of the various ingredients used in the
operation, as the same will be constantly varying according to the heat
of the solution and the state of electric current and the quantity of metal
becoming absorbed, whereby an addition to or diminution in the quantities
of the various ingredients will be necessitated, which will vary con-
tinually, and can only be determined and altered by a practical operator
in accordance with the requirements of his solution. In the event of the
equilibrium of the solution not being maintained in so far as regards
the heat, quantity of metal, electricity, or chemicals used, the deposit
obtained from this solution is liable to become rough, in which event
the articles should be taken out and brushed with wire brushes (as is
usual in the manufacture of electro-coated or plated articles), and again
passed into the solution; and in the case of large articles the granular,
soft, or surplus deposit must be removed by an ordinary brush or a cloth
and sand, or by any other convenient method.
The metals which I am enabled to coat by this process are copper,
brass, silver, iron, nickel, zinc, lead, Britannia metal, manganese, gold,
steel, platina, or any useful compound of the above.
This Invention is also applicable to the prevention of the oxidization or
tarnishing of silver surfaces by the deposition of slight or heavy coatings
of tin upon the surface of the silver exposed to atmospheric influence.
The solution herein-before described may be made from several
precipitates of tin, provided always that potassic hydrate, cyanide of

page_text: potassium, and calcic hydrate are left in the final solution; and also
the same result may be obtained by driving the tin into the solution
above named by means of clectricity; but the means I have quoted I
believe to be the most convenient for the chemist.
i
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Edward Bingham, in the Great Seal Patent
Office on the 28th March 1871..
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
EDWARD BINGHAM, of Victoria Park, Sheffield, in the County of York;
Manufacturer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-cighth day of September, in
the year of our Lord One thousand eight hundred and seventy, in the
thirty-fourth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said John Edward Bingham, Her
special licence that I, the said John Edward Bingham, my exccutors,
administrators, and assigns, or such others as I, the said John Edward
Bingham, 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 ELECTRO-DEPOSITION OF TIN, WHICH IMPROVEMENTS ARE
APPLICABLE TO THE PREVENTION OF THE OXIDIZATION OR TARNISHING OF SILVER
SURFACES, AND AS A COATING FOR OTHER METALS," upon the condition
(amongst others) that I, the said John Edward Bingham, 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 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 John Edward Bingham, do hereby

page_text: is to be performed, to be particularly described and ascertained in and by
the following statement, that is to say:-
In carrying out my Invention of improvements in the electro-deposition
of tin I first take a given quantity of tin, by preference in a pure state,
but what is commercially known and sold as tin may be employed,
which I dissolve in chlorhydric acid, and precipitate the same by means
of a solution of crude potassic hydrate; I then wash the precipitated tin
free from acid, after which I add a quantity of potassic hydrate and also
of cyanide of potassium, and then raise the temperature by preference
to a point just below that at which the solution would boil; this, however,
may be varied, and when the solution has been thus heated I add a
quantity of solution of calcic hydrate. In the solution thus obtained I
suspend sheets of tin and also the articles to be coated with the same,
which will be previously prepared as is usual when coating articles by
the electro-deposition of metal, and will be understood by persons
acquainted with the clectro-deposition of metals. The tin and the
articles to be coated are then connected with the battery in the usual
manner, and the articles to be coated are retained a greater or less time
in the solution according to the quantity or thickness of tin required to
be deposited on their surface.
The quantity of ingredients may be varied, but I have used with
advantage a bath of the following composition:-In ten gallons of water
eight hundred and twenty-six grains of tin in solution, two and a half
pounds of potassic hydrate, half a pound of cyanide of potassium, and
one hundred grains of calcic hydrate. These proportions will be con-
stantly varying according to the heat of the solution, and the state of
electric current, and the quantity of metal becoming dissolved and
deposited. Thus a variation in the quantities of the several ingredients
will be caused which can only be determined and altered by a practical
operator in accordance with the requirements of his solution. In the
event of the equilibrium of the solution not being maintained in so far
as regards the heat, quantity of metal, electricity, or chemicals used, the
deposit obtained from this solution is liable to become rough, in which
event the article should be taken out and brushed with wire brushes (as
is usual in the manufacture of electro-coated or plated articles) and
again passed into the solution; and in the case of large articles the
granular, soft, or surplus deposit must be removed by an ordinary brush,
or a cloth and sand, or by any other convenient method.

page_text: The metals and alloys which I am enabled to coat by this process
are copper, brass, silver, iron, nickel, zinc; lead, Britannia metal, nickel,
silver, alloys of manganese, gold, steel, platinum, or any useful alloys of
the above.
This Invention is also applicable to the prevention of the oxidization or
tarnishing of silver surfaces by the deposition of slight or heavy coatings
of tin upon the surface of the silver exposed to atmospheric influence.
The solution herein-before described may be made from several
precipitates of tin, provided always that potassic hydrate, cyanide of
potassium, and calcic hydrate are left in the final solution; and also
the same result may be obtained by dissolving the tin into the solution
above named by the aid of electricity; but the means I have quoted I
believe to be the most convenient for the chemist.
Having thus described the nature of my Invention, and the means by
which the same may be carried into effect, I would have it understood
that I do not confine myself to the precise mode of producing the
solutions, or to the proportions given; but what I do claim is the pro-
duction of solutions for the purpose of obtaining the electro-deposition
of tin upon metallic surfaces, substantially as described.
In witness whereof, I, the said John Edward Bingham, have here-
unto set my hand and seal, this Twenty-fifth day of March, in
the year of our Lord One thousand eight hundred and seventy-
one.
5 Witness,
HEBER WARD.
JOHN EDWARD BINGHAM. (L.S.)