IMPROVEMENTS IN TREATING MATTERS CONTAINING LEAD, TIN,, ANTIMONY, ZINC, OR SILVER, AND IN OBTAINING SUCH METALS OR PRODUCTS THEREOF
Year: 1852

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
RICHARDSON, of Newcastle-upon-Tyne, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Twenty-eighth day of
April, One thousand eight hundred and fifty-two, in the fifteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Thomas Richardson, my exors, adññors, and assigns, Her especial
licence, full power, sole privilege and authority that I, the said Thomas
Richardson, my exors, adiñors, and assigns, or such others as I, the said
Thomas Richardson, 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, my
Invention of "IMPROVEMENTS IN TREATING MATTERS CONTAINING LEAD, TIN,,
ANTIMONY, ZINC, OR SILVER, AND IN OBTAINING SUCH METALS OR PRODUCTS
THEREOF;" in which said Letters Patent is contained a proviso, that I, the said
Thomas Richardson, shall cause a particular description of the nature of my
said Invention, and in what manner the same is to be performed, by an instru-
ment in writing under my hand and seal, to be inrolled in Her 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..
NOW KNOW YE, that in compliance with the said proviso, I, the said
Thomas Richardson, do hereby declare that the nature of my said Invention,

page_text: 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 :-
The first part of my Invention consists in separating certain metallic oxides
from each other. In the process at present in use for softening the hard
leads of commerce a quantity of metallic oxide is formed, composed of oxide of
lead with varying proportions of oxide of antimony or tin, as the case may be.
This mixed oxide so produced is one of the substances I employ, or I take the
alloys of copper and tin, which are sometimes sold as waste products, and
expose them in an ordinary reverberatory furnace to a current of hot air, either
in a melted state or as sheets, or in lumps, granulated or not, until they are
converted into oxides of the metals. Having obtained these mixed metals in
the form of oxides, I employ oxides of lead and tin, or lead and antimony in
place of litharge, with acetic or nitric acid, with precisely the same utensils and
precautions as are at present necessary for the manufacture of acetate or
nitrate of lead. The acetic or nitric acid dissolves out the oxide of lead, and
leaves the oxide of tin or antimony, which may then be reduced to the metallic
state by any of the methods now practised by the smelters of these metals.
the mixed metals have been tin and copper upon which I have operated, I employ
their mixed oxides instead of the oxide of copper with acetic or sulphuric acid,
for the manufacture of acetate or sulphate of copper. The process is con-
ducted in the manner now practised by manufacturers of these salts, and the
oxide of tin which is left may be reduced as already explained. Instead of
reducing the oxide of tin after it has been freed from the adhering salts of lead
or copper by simply washing with water, I employ it in the place of the metal
or ore for the production of muriate of tin or stannate of soda by any of the
methods now in use for the manufacture of these salts.
If
The second part of my Invention consists in reducing the mixed oxides of
lead and antimony, already named, in an ordinary reverberatory furnace along
with common alkali and carbon. I grind about twenty hundredweight of the
oxides of lead and antimony, obtained by calcining hard lead of commerce with
twenty-eight pounds of alkali and one hundred and twelve pounds of coal to a
coarse powder, and subject the mixture to a very low heat in the usual
reducing furnace. If the antimony exceed from twenty to thirty per cent. of
the mixed oxides, I increase the quantity of alkali in the proportion of one
pound to every per cent. of antimony above that named. The mixed metal I
again submit to calcination in an iron pan holding about ten tons of the metal
and the oxide which is formed during the process contains a much larger
quantity of antimony than the previous one, while nearly all the silver remains
in the soft lead. This mixed oxide of antimony and lead is ground and

page_text: lixiviated in the usual manner, and subjected to the action of hot air in an
ordinary red lead furnace until the lead has been converted into the red oxide.
This product is again lixiviated and dried. In this state it may be used as a
pigment, or substituted for red lead in the manufacture of flint or other kinds
of glass.
The third part of my Invention consists in preparing sulphuret of lead for
reduction. It is well known that in smelting lead ores the first process is to
submit them to the operation of roasting, so as to expel part of the sulphur,
and convert another portion into sulphate of lead. This roasting process is
either conducted in a distinct furnace, in the smelting furnace itself, or by
means of the waste heat of this latter furnace conveyed to a furnace adjoining
or constructed above it. The process lasts from one to thirty or forty hours,
according to the nature of the ore. I employ this same process for preparing
the lead ores for smelting, but I conduct the operation at a dull red heat
until the whole or nearly the whole of the sulphur is expelled. The ore must
never be heated to such an extent that it becomes pasty, and I employ a
reverberatory furnace with five or six flats. The ore is charged on the flat
furthest from the fire, and gradually removed as the roasting proceeds to that
nearest the fire-bridge, by which time it is capable of sustaining a stronger
heat without softening, and parts more readily and completely with the
remaining sulphur. The time varies with the nature of the ore from thirty.
hours to three, four, of five days. The ore so roasted I smelt by any of the
plans at present in use, or by means of the furnace to be described.
The fourth part of my Invention consists in smelting certain matters con-
taining silver and lead in a furnace of peculiar construction.
In smelting
zinc ores by the Belgian or Silesian plans, I find the ashes, impure oxide, and
the retort or vessel in which the distillation is conducted, retain all or nearly
all the silver which existed in the zinc ore in its original state. The silver
and gold ores or sweepings, as imported into this country, cannot be submitted
to the ordinary process of roasting without considerable loss. I therefore mix
such materials, or that resulting as above named from the distillation of zinc
ores, with the waste oxides of lead and antimony already described, or with
the lead ores roasted by my plan, or with what are known as grey slags ground
to a tolerable fine powder, and sufficient good strong clay to make the whole
bind; and I mould the mixed materials into small bricks, which are dried at
a low temperature. I also use the grey slags already named alone, or mixed
with about ten to twenty per cent. of their weight of common galena as they
come from the present furnace for smelting lead ore, and reduce the whole in
a furnace which I proceed to describe:-A is the body of the furnace, formed

page_text: of a single brick about three feet diameter, and five feet from the air or blast
pipe to the charging door. The bottom is composed of clay and ground coke,
or carbon well beaten down, which is cut into the form shown in the sketch
annexed, and carefully annealed. The materials are thrown into the furnace
level with the charging door b, and a fine spray of water is made to play
upon their surface from a rose situated at C. The front of the furnace is
supported by a piece of metal casing d, over which the slag flows, either into
water or metal tubs. When the lead has accumulated in sufficient quantity
in the hearth, it is tapped into a pot at the point e. The furnace may be
worked by means of a blast thrown into the furnace by the tuyeres f, f, f, or
by increasing the number of these openings to five or six and connecting the
furnace with a tall chimney, when the natural draught will be sufficient. In
other respects the mode of managing the furnace is precisely similar to that of
an iron blast furnace. When the body of the furnace is worked out, the upper
portion g, supported by four metal pillars and binders h, h, h, h, remain
untouched, and thus saves some cost in renewing the lower portion. I
am aware that a furnace of a somewhat similar construction has been employed
elsewhere, but the loss of lead has always been so serious as to prevent its
general adoption. This furnace managed with care, and attention being had
to the nature of the material charged as detailed above, the loss of lead is
trifling, and no lead fume is produced.
In witness whereof, I, the said Thomas Richardson, have hereunto set
my hand and seal, this Twenty-fifth day of October, One thousand eight
hundred and fifty-two...