IMPROVEMENTS IN COVERING AND COATING CERTAIN METALS
Year: 1838

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, we, GEORGE
RICHARDS ELKINGTON and OGLETHORPE WAKELIN BARRATT, of Birmingham, in
the County of Warwick, Manufacturer, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Twenty-fourth day of July, in the second year of Her reign,.
did, for Herself, Her heirs and successors, give and grant unto us, the said
George Richards Elkington and Oglethorpe Wakelin Barratt, Her especial
license, full power, sole privilege and authority, that we, the said George
Richards Elkington and Oglethorpe Wakelin Barratt, our exors, admors, and
assigns, or such others as we, the said George Richards Elkington and Ogle-
thorpe Wakelin Barratt, our exors, adñors, 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,
our Invention of "IMPROVEMENTS IN COVERING AND COATING CERTAIN METALS;"
in which said Letters Patent is contained a proviso that we, the said George
Richards Elkington and Oglethorpe Wakelin Barratt, or one of us, shall
cause a particular description of the nature of our said Invention, and in what.
manner the same is to be performed, to be inrolled in Her said Majesty's

page_text: 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.
NOW KNOW YE, that in compliance with the said proviso, we, the said
George Richards Elkington and Oglethorpe Wakelin Barratt, do hereby
declare that the nature of our Invention, and the manner in which the same
is to be performed, are fully described and ascertained in and by the following
statement thereof (that is to say):-
And we would in the
Our Invention consists of certain modes, hereafter described, for coating
metals with zinc, and with zinc and mercury, for the purpose of preventing
oxydation, and a mode for coloring iron and steel.
outset remark that we are aware that that metals have been before coated
with zinc to prevent oxydation; we therefore only claim the modes hereafter
described.
Our improvements in coating and colouring certain metals are effected by
the following process:-In order to coat copper and brass with zinc, we mix
in an earthen vessel seven parts of muriatic acid (spec. gravity about 116)
and one hundred parts of water, both by weight, and to these we add four
parts of zinc in the state of powder or pieces; we allow these to remain
twenty-four hours, or until the acid and zinc cease to act upon each other,
and the solution thus obtained we pour into a convenient vessel for boiling it,
adding a quantity of zinc in powder or in thin pieces. While boiling we
immerse the articles therein, bringing them in contact with the metallic zinc,
they will speedily become coated therewith; we then remove and wash them
with water and dry them. In using this solution of zinc, if the articles are
of iron or steel, we previously coat them with copper, and which we effect as
follows: We first clean or pickle the articles in dilute sulphuric acid,
composed of one part concentrated acid to sixteen parts of water, and having
prepared a solution of sulphate of copper, commonly called blue vitriol, we
immerse the iron therein, while cold, for a few seconds, and speedily remove
and wash it; this we repeat one, two, or three times, or until we find
the iron perfectly coated. Care must be taken not to allow it to
remain too long in the solution of copper, or the copper precipitated on
the surfaces becomes loose. If a stronger coating of zinc be required,
we repeat the processes of coppering and zincing. And we have also found
that if the articles, when of copper or if of iron, after they have been
coppered, are introduced into a dilute solution of nitrate of mercury and then
again boiled in the solution of zinc, that the same object is obtained. The
nitrate or any other convenient solution of copper may be substituted for the

page_text: sulphate; or we coat iron and steel with zinc in the following manner :-We
take, dilute muriatic acid in about the proportion of one part acid (specific
gravity 116) and thirty parts of water, into this we introduce a quantity
of zinc in powder or in small pieces; the articles of iron are then to be
placed in the acid and kept in contact with the zinc during the process,
which will require from two to five minutes, or until they are evidently coated
with zinc; we then remove, wash, and dry them as before. We also coat
various metals, as iron, steel, copper, brass, &c., with the amalgam of zinc;
and although this may be effected by using the two metals in almost any
proportions, we have found that six or seven parts of zinc with one part of
mercury to answer best, and which we amalgamate by heat or by agitating the
two metals in contact with a dilute muriatic or other convenient acid, the zinc
being previously granulated or reduced to small pieces. To this amalgamated
zinc, when effected by heat, we add dilute acid as before, and then introduce the
articles, which may require to be kept occasionally stirring, in contact with it.
Or, instead of using the muriatic acid, we employ certain salts, as the muriate
or sulphate of ammonia, in the proportion of one ounce of the salt to thirty
ounces of water or thereabouts; and other acids than the muriatic may bo
employed, as the acetic, sulphuric, &c., and which require no other directions
than to employ them of about the same strength as directed for the muriatic
acid. We prefer to employ these solutions in a hot or boiling state, as the
effect is thereby obtained in a shorter period, but the processes where
the free acid is used may be successfully performed in a cold state, the
acid and water to be added occasionally as the solution becomes reduced
in strength or quantity by the boiling or action upon the metals to be
coated. We also employ the amalgam of zinc in a melted state for some
articles, in which case, and particularly if they are of iron, they require to be
well pickled or cleaned, and also to be immersed in a solution of muriate of
ammonia, to induce the perfect adhesion of the amalgam of zine, and which
may be varied in almost any proportion of the two metals, but we prefer to
use the proportions now given. The oxides of the metals may also be used in
the same manner, instead of the metals or in conjunction with them, as, for
example, a solution of zinc may be made with the oxide of that metal instead
of using the metal itself, and so also with the oxides of mercury.
And
whereas it is well known that iron previously cleaned may be coated with tin
and zinc by immersion in these metals when fused, part of our improvements
apply to the coating of metals by means of the before-described processes in
conjunction with the coating obtained from the fused metals, and which we

page_text: employ either previous or subsequent to the fused coating. To color iron and
steel to imitate brass, we first coat the iron or steel by means of a solution of
copper, as always described; and having afterwards boiled it in the saturated
solution of zinc, having excess of zinc therein, until perfectly covered, we
remove it and dry it in saw dust, and then submit it to heat in a closed oven
until the required color is obtained, and which is easily observed by looking
occasionally at the articles during the process; they are afterwards to be pickled
in a dilute acid, and washed and dried.
Having thus described the nature of our Invention, we would remark that
the modes herein described may in some degree be varied so long as our
Invention be retained, and although we have necessarily mentioned matters
and processes which are not new, we make no claim thereto. And we would.
remark that we are aware that a process called "Semiloring" (simile l'or)
has been before practised for coloring copper and brass, which consists in
obtaining to the surface a thin coating of zinc, and submitting the articles so
prepared to the action of heat till a color approaching to that of gold is
obtained. Now the object of our Invention, so far as it relates to coating
copper and brass, is to obtain a good and efficient coating of zinc on the
surfaces in order to prevent or retard oxydation; we, therefore, do not apply
the process of heat, which would be prejudicial to the coating of zinc, for that
purpose; and we would have it understood that what we claim is,―
First, the mode herein described of coating copper and brass for preventing
oxydation.
Secondly, we claim the combined use of mercury and zinc in coating of
metals to prevent oxydation.
Thirdly, we claim the mode herein described of coating iron and steel with
zinc. to prevent oxydation by means of a solution of zinc.
Fourthly, we claim the mode of coating iron and steel with zinc by first
coating with copper. And,
Fifthly, we claim the mode of coloring iron and steel by coating the same
with copper, then with zinc, and afterwards submitting the articles to heat in
a similar manner to what has heretofore been performed in copper and brass
by the process known as semiloring (simili l'or).
In witness whereof, I, the said George Richards Elkington, have
hereunto set my hand and seal, this Twenty-third day of January, One
thousand eight hundred and thirty-nine..
(L.S.) GEORGE RICHARDS ELKINGTON.

page_text: AND BE IT REMEMBERED, that on the Twenty-third day of January,
in the year of our Lord 1839, the aforesaid George Richards Elkington came
before our said Lady the Queen in Her Chancery, and acknowledged the
Specification aforesaid, and all and every thing therein contained and
specified, in form above written. And also the Specification aforesaid was
stamped according to the tenor of the Statute made for that purpose.
Inrolled the Twenty-fourth day of January, in the year of our Lord One
thousand eight hundred and thirty-nine.