IMPROVEMENTS IN PLATING GLASS TO RENDER IT REPLECTIVE
Year: 1856

page_text: LETTERS PATENT to Richard Archibald Broomau, of 166, Fleet Street, in
the City of London, Patent Agent, for the Invention of "IMPROVEMENTS
IN PLATING GLASS TO RENDER IT REPLECTIVE."-A communication
Sealed the 21st October 1836, and dated the 4th June 1856.
PROVISIONAL SPECIFICATION left by the said Richard Archibald Brooman
at the Office of the Commissioners of Patents, with his Petition, on the
4th June 1856.
I, RICHARD ARCHIBALD BROOMAN, of 166, Fleet Street, in the City of
London, Patent Agent, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN PLATING GLASS TO RENDER IT REFLECTIVE," (communicated to
me by a foreigner residing abroad.) to be as follows:-
In this Invention neither mercury,nor oxide nor nitrate of silver isemployed.
The Inventor makes use of dry or moist currents of air impregnated with
gas or gases evaporated from metallicsolutions, mixed under certain conditions
with vegetable substances. These gases are fixed upon glass by means of
electric or electro-magnetic currents applied through suitable apparatuses,
whereby sufficiently high temperatures are obtained to fuse the metals, salts,
and oxides held by gases employed to form the plating upon the largest sized
glasses; and the results of this process are:-First. the glass to which the

page_text: plating is applied is rendered reflective instantly, and as perfectly as if the
usual mercurial plating process had been followed; second, the reflection is
obtained without affecting the quality, the color, or the polish of the glass;
third, the plating is not injuriously affected by damp, wet, or the greatest
heat to which a glass is likely to be exposed when placed in a room or on a
wall. It resists the effects of sea water, and is not affected by rubbing; it
does not require the protection of flanneland back pieces, which are necessary
for mercurial plating.
The following are among the substances used:-Black oxide or oxide of
iron, salts of tin, tiu in grains, protoxide of tin, salts of zinc, sulphate of zinc,
hydrosulphate of ammonia, acetate of lead. acetate of alumina, iodine, meta-
gallic salts, chloride of gold,carbonate of potass, salts of soda, manganese, salt
of alum,bromines,sulphuric, hydrochloric, and benzoic acids, ether,crystallized
hematine (l'hématine crystallisée), sulphate of copper, muriatic acid, and
generallyall acids producing theeffects of mordants, of reaction, and of solvents
in printing.
Although not necessary, yet. if desired to protect this plating, there may be
applied over it a coating composed of some of the following substances:-Tar.
galipot,plaster, lime, cement, whiting mixed with glue, chalk, ochre,oil colors
mixed with drying oils.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Richard Archibald Brooman in the Great Seal Paent Office
on the 4th December 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, RICHARD
ARCHIBALD BROOMAN, of 166. Fleet Street, in the City of London, Patent
Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourth day of June, in the year of our Lord One
thousand eight hundred and fifty-six, in the nineteenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Richard Archibald Brooman, Her special licence that I, the said Richard
Archibald Brooman, myexecutors, administrators, and assigns, or such others
as I, the said Richard Archibald Brooman, my executors, administrators, and
assigns, should at any time agree with, and no others, from time to time

page_text: and at all times thereafter during the term therein expressed, should and
lawfully might make, use, exercise, and vend, withinthe United Kingdom of
Great Britain and Ireland, the Channel Islands, and Isle of Man. an Invention
for "IMPROVEMENTS IN PLATING GLASS TO RENDER IT REFLECTIVE," (communicated
to me by a foreigner residing abroad, upon the condition (amongst others)
that I. the said Richard Archibald Brooman, my executors or adminis
trators, by an instrument in writing under my, or their, or one of their
hands and scads, 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 Richard Archibald Brooman, do hereby
declare the nature of the said fuvention, and in what manner the same is
to be perforined, to be particularly described and ascertained in and by the
following statement, reference being had to the Drawings liereunto annexed,
that is to say
.
This Invention is stated by the Inventor to consist in plating glass by
depositing upon it certain metallic and other substances, as herein-after
named, decomposed by the action of acid or acids, as in the galvanic
battery, and in a gaseous or vapoury form, and in reducing and fixing such
metallic and other plating agents in such gaseous form by the agency of
electricity or galvanism, or both, upon the glass, ito a metallic or solid
state, whereby glass will be rendered reflective.
The Invention also consists in certain arrangements of machinery for
carrying it into effect.
All or nearly all metals and metallic salts will be capable of being decor:-
posed and of being deposited upon glass, when they are made to form.an
element in or make part of a galvanic battery; but it will at once be obvious
that the lighter the color of the metal, the greater will be its fitness for
reudering glass reflective.
As it will be at once apparent, after the nature of this Invention has been
set forth, that there will be numerous different methods of carrying it into
effect, and as the agents employed may be varied by one being substituted for
another, and by different proportions being used with more or less beneficial
effect, it is not proposed to set forth herein every form or mixture of plating
agents which may be employed; but first will be pointed out such as the
Inventor deems most suited for the purpose of this Invention, and then one
set of ingredients will be described, together with the machinery, which the
Inventor states he has found well suited to carry it into practical effect.

page_text: The following are among the substances used:-Black oxide or oxide of
iron, ethiop's martial, salts of tin, tin in grains, protoxide of tin, salts of
zinc, sulphate of zinc, hydrosulphate of ammonia, acetate of lead, acetate of
alumina, iodine, meta-gallic salts, chloride of gold, carbonate of potassa,
salts of soda, manganese, salt of alum, bromines, sulphuric, hydrochloric,
and benzoic acids, ether, crystallized hemantine (l'hémantine crystallisée),
sulphate of copper, muriatic acid, and acids generally.
The manner of operation is as follows:-The Inventor takes a plate of glass.
and perfectly cleans the surface upon which the gas is to be applied, and
I then places the clean surface upon a plate pierced with numerous small
holes, which plate is the top of a flat chamber which forms part of the
machine, of which Figure 1 is a side, and Figure 2 an end elevation.
A, A, is the framework, the upper surface of which is planed true, and
formed with a flange ao; B is a roller, the axis of which revolves in fixed
bearings, and has keyed to it the toothed wheels C,D) one at each end; E is
a cylinder, to one end of which the toothed wheel Fis attached, the axis of
this cylinder revolves ou journals, which are free to rise and fall in slots
formed in each of the standards G.G, as will be seen by the Drawings; the
axes of the roller and cylinder are not in the same vertical line, that of the
.roller being slightly in advance of that of the cylinder. Forked rods H, H, on
each side of the machine, are attached to the journals, and are connected at
;bottom to two levers J,J,and the parallelism and equal rising and falling of
the axis of the cylinder E at both ends is secured by strong transverse coupling
.bars boil at the side and front of the machine; b is a counterpoise, to facili-
tate the lifting of the cylinder; K is a roller, the axis of which is free to rise
and fall in slots in the upper part of the standards C, G; connecting rods at
each side of the machine communicate with the journals or axis of the cylin
der E, and the distance between the roller Kand this cylinder being once
regulated, they each. rise or fall through an equal space, and consequently
preserve their relative positions; L. is an endless band of soft, yielding, or
compressible material passing round the cylinder E and roller K; M is the
hollow chamber with the perforated top, before named; c, c, are friction
wheels connected to the ends of the chamber at bottom, and which travel upon
the smooth surface of the upper part of the frame; N is a pinion for driving
the roller B through the toothed wheel C, while the toothed wheel D causes
the cylinder E to revolve with the roller B through the toothed wheel F.
Care must be taken that the cylinder E, roller B, and top and bottom of the
hollow chamber are true, aud the distance between the cylinder and roller.
having been regulated to allow of the chamber with a sheet of glass passing.

page_text: gas
over one and under the other, the operation of coating the under surface of
the glass with the gaseous fumes has to be performed. At one end of the
hollow chamber is a hollow ferrule or portion of a tube screw-threaded, or
there may be two or more such ferrules; and to as many as there are is
attached, by screw couplings or joints, a flexible (preferring caoutchouc or
gutta percha) tube; each tube has a stop-cock, and is connected to a
receiver in the form of a cover placed over a trough, vessel, or vessels in
which the action of decomposing the metals and substances hereafter named
is being carried on, in such manner as to collect all the products given off.
The troughs or vessels must be of gutta percha, earthenware, or of some other
material not acted upon by acids. Each trough or vessel contains sodium,
cadmiuin, zinc, ethiops martial, sulphuric, nitric, muriatic, and meta-gallie
and boric acids, in sufficient quantities and strength to excite the metals to
action.
As soon as the metals and substances begin to be decomposed and to passoff
in a gaseous form, the stop-cocks are opened, when the gascous fumes having
no other outlet, fill the hollow chamber, and passing through the apertures in
the perforated top, pass on to the glass. As soon as the stop-cocks are opened,
the hollow chamber and glass are advanced, until the bottom thereof comes in
contact with the roller B, which being caused to rotate, drives forward the
chamber and glass, which latter receives a slight pressure through the soft
endless belt, and effectually secures the gaseous coating through all the per-
forations in the top of the chamber on to the glass; and in order to distribute
the gaseous fumes evenly and smoothly, a roller is fitted at one end of the
hollow chamber, over which the glass is pushed on its passage on to the
achine, where the electric currents are applied to fix and recompose the
metals and other substances on the glass. as follows:-
Figure 3 is a side elevation in perspective, and Figure 4 an end view, of the
machine for applying the electric currents and for fixing the substances upon
the glass. Upon standards A, A, there is askeleton platform or frame B, B, the
whole of which is insulated by the insertion in the standards of glass or other
non-conducting material. A hollow chamber, with the upper surface perfectly
smooth and solid, is mounted upon friction wheels, formed of ivory, glass,
or other non-conducting substance, which travel upon the sides of the frame
or skeleton platform. The Inventor prefers the upper surface of the hollow
chamber to be of bronze. For greater convenience, rollers of wood or rollers
clothed with a non-conducting substauce may be mounted under the hollow
chamber, in order to cause it to advance by frictional contact. The chamber

page_text: may, however, be pushed to-and-fro otherwise; and for the placing of the
glass thereon I mount a roller clothed with a soft material at the end where the
glass is to be received on to it. C.C,are side frames, which act as guides to the
chamber, and which serve to support a cloth for covering over the chamberand
the glass while the fixing is being performed; D is a chamber open at top,and
with the edges coming close to the bottom of the hollow chamber, for contain-
ing a spirit or other lamp, or gas burner; E is a pillar containing a galvanic
battery, from which the wires are conducted and connected to some convenient
part of the hollow chamber; Fis a glass disc for generating frictional electricity;
G, G, G, are a series of strong oval vessels formed in metal and lined with an
acid-resisting material; these vessels are screwed into one another, and the
lowest vessel is furnished with a brush or skin, which being rubbed against
by the glass, electricity is generated and received by the lowest vessel; cach
of the four lowest vessels contains a mixture of boric and sulphuric acids, and
the electricity aids in developing a highly heating gas, which passing through
the other vessels shewn in the Drawing, finally enters the hollow chamber
through a metal pipe, provided with suitable joints and elbows to suit the
changing position of the hollow chamber. All being in readiness, the plate
of glass. with the metallic fumes thereon, is passed from the fume-depositing
machine on to the solid top of the hollow chamber; in the fixing machine the
wires are connected with the battery, communication is opened for the in-flow
of the beating gases, the lamp in the case is ignited, and the cloth is lowered
over the end frames; as soon as the current is applied the substances will be
recomposed and fixed on the glass, and the glass will be thereby rendered
reflective, although the Inventor states he finds heat aids the electric current,
yet it is not absolutely necessary, and the current itself may be applied alone.
In such case, a solid flat plate might be substituted for the hollow chamber.
The reflecting composition will be found to adhere to the glass perfectly well,
and will not be easily rubbed off'; but.if thought desirable,a protective coating,
composed of some of the following substances, may be applied :-Tar,
galipot, plaster, lime, cement, whiting mixed with glue, chalk, ochre, oil
colors made up with drying oils.
And having now described the nature of the said Invention, and in what
manner the same is to be perforined, I declare that I claim,-
First, the plating of glass in order to renderit reflective,by applying thereon
metallic and other fumes obtained by the decomposition of metals and other
substances, as herein-before described, and the recomposing and fixing ofsuch
metals and substances from the fumes upon the glass by the agency of
electricity.

page_text: Second, the machinery herein-before described and represented in the
Drawings annexed for the plating of glass.
In witness whereof, I, the said Richard Archibald Brooman, have
hereunto set my hand and seal, this Third day of December, One
thousand eight hundred and fifty-six.
R. A. BROOMAN. (L.S.)