IMPROVEMENTS IN THE SEPARATION OF SILVER AND LEAD
Year: 1860

page_text: LETTERS PATENT to Philip John Worsley, of Rotherhithe, in the County
of Surrey, for the Invention of "IMPROVEMENTS IN THE SEPARATION OF
SILVER AND LEAD."
Sealed the 29th June 1860, and dated the 4th January 1860.
PROVISIONAL SPECIFICATION left by the said Philip John Worsley, at
the Office of the Commissioners of Patents, with his Petition, on the
4th January 1860.
I, PHILIP JOHN WORSLEY, of Rotherhithe, in the County of Surrey, do
hereby declare the nature of the Invention for "IMPROVEMENTS IN THE
SEPARATION OF SILVER AND LEAD," to be as follows:-
The separation of silver and lead as usually practised consists of two
operations. The first is a concentration by crystallization of the lead, whereby
the silver is concentrated in a small quantity of lead, which thus becomes what
is called "rich lead." The second operation is the separation of the silver and
lead in the rich lead by cupellation. The separation of silver and lead by
crystallization as hitherto carried out has been effected by melting the mixed
metals in an iron pot, cooling the melted alloy, and stirring it by hand until
what are called crystals begin to form. The crystals are then separated from
the fluid alloy. This is usually done in one of two ways. Either the crystals
are lifted out of the pot by means of ladles pierced with holes, which allow
the fluid alloy to drain back into the pot; or else a pierced ladle or other
perforated vessel is pressed into the mixture of crystals and fluid alloy con-
tained in the melting or crystallizing pot, so as to allow the fluid rich alloy tc
flow into the pierced ladle or vessel while the crystals remain outside it
fluid alloy is then ladled out of the crystallizing pot by hand ladles.
The

page_text: My improvements relate to the separation of the rich alloy from the crystals,
and consist, first, in drawing off the fluid alloy from the crystals by means of
a hole or holes in the pot or vessel in which the mixture of fluid alloy and
crystals is contained. For this purpose the crystallizing pot or vessel in which
the mixture of fluid alloy and crystals is contained, instead of being a plain
pot, as hitherto, has a hole or holes through it, by which any liquid inside the
pot or vessel can run out; this hole or holes is kept stopped by a plug, cock,
or other usual method during the melting and cooling, until the operator
considers the quantity of crystals formed sufficient; the hole is then opened,
and the liquid alloy run out by the hole, while the crystals remain in the pot
or vessel. To aid the draining of the crystals, they may be stirred as in the
ordinary process, until the whole of the liquid alloy has been drawn off. In
addition to the perforated crystallizing pot, I use a strainer or false bottom,
made of iron or other suitable material, pierced with holes of suitable size
placed over the hole or holes in the crystallizing pot, so as to prevent the
crystals from passing through the holo or holes, while the liquid alloy is
allowed to drain through. This strainer may either be loose, and merely laid
over the hole or holes, or it may be fastened down, or it may be made in one
piece with the crystallizing pot or vessel. Instead of stirring by hand with a
slice, as is usually done, I use a mechanical stirrer, consisting of an upright
shaft connected by gearing or otherwise with a steam engine, water wheel, or
other source of power, so that it is turned around by the said power. This
upright shaft is fixed in the centre of the crystallizing pot, with a bearing at
top and bottom, and carries arms radiating from it extending to the sides of
the crystallizing pot. The shape and number of these arms is not very
material; but I prefer flat arms with a thin edge foremost and inclined so
that the front edge is lower than the back.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Philip John Worsley, in the Great Seal Patent Office on
the 4th July 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, PHILIP
JOHN WORSLEY, of Rotherhithe, in the County of Surrey, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourth day of January, in the year of our Lord
One thousand eight hundred and sixty, in the twenty-third year of Her a
reign, did, for Herself, Her heirs and successors, give and grant unto me, the

page_text: said Philip John Worsley, Her special licence that I, the said Philip
John Worsley, my executors, administrators, and assigns, or such others
as I, the said Philip John Worsley, 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 Inven-
tion for "IMPROVEMENTS IN THE SEPARATION OF SILVER AND LEAD," upon the
condition (amongst others) that I, the said Philip John Worsley, 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 Philip John Worsley, 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 thereof, that is to say :-
The separation of silver and lead as usually practised consists of two
operations. The first is a concentration by crystallization of the lead, whereby
the silver is concentrated in a small quantity of lead, which thus becomes what
is called "rich lead." The second operation is the separation of the silver and
lead in the rich lend by cupellation. The separation of silver and lead by
crystallization as hitherto carried out has been effected by melting the mixed
metals in an iron pot, cooling the melted alloy, and stirring it by hand until
what are called crystals begin to form. The crystals are then separated from
the fluid alloy. This is usually done in one of two ways. Either the crystals
are lifted out of the pot by means of ladles pierced with holes, which allow the
fluid alloy to drain back into the pot, or else a pierced ladle or other perforated
vessel is pressed into the mixture of crystals and fluid alloy contained in the
melting or crystallizing pot, so as to allow the fluid rich alloy to flow in to the
pierced ladle or vessel while the crystals remain outside it. The fluid alloy. is
then ladled out of the crystallizing pot by hand ladles.
My improvements relate to the separation of the rich alloy from the
crystals, and consist, first, in drawing off the fluid alloy from the crystals by
means of a hole or holes in the pot or vessel in which the mixture of fluid
alloy and crystals is contained; for this purpose the crystallizing pot or vessel
in which the mixture of fluid alloy and crystals is contained instead of being a

page_text: plain pot as hitherto, has a hole or holes through it by which any liquid inside
the pot or vessel can run out. This hole or holes is kept stopped by a plug, cock,
or other usual method during the melting and cooling, until the operator considers
the quantity of crystals formed sufficient. The hole is then opened and the
liquid alloy run out by the hole, while the crystals remain in the pot or vessel..
To aid the draining of the crystals they may be stirred as in the ordinary
process, until the whole of the liquid alloy has been drawn off. In addition to
the perforated crystallizing pot I use a strainer or false bottom made of iron or
other suitable material pierced with holes of suitable size placed over the hole
or holes in the crystallizing pot, so as to prevent the crystals from passing
through the hole or holes while the liquid alloy is allowed to drain through.
The strainer may either be loose and merely laid over the hole or holes, or it
may be fastened down or it may be made in one piece with the crystallizing
pot or vessel.
In carrying my Invention into effect I prefer to use pots for crystallizing
the mixed metals similar to those used in the ordinary process, but towards
the bottom, that is to say, about 2 inches above the bottom of the inside of the
pot have a hole drilled through the pot nearly horizontally. This hole may
be from a quarter to half an inch in diameter. Over this hole I fasten a
strainer consisting of sheet iron pierced with holes; these holes should be
small, not more than one-sixteenth of an inch in diameter, but as close
together as is consistent with the strength of the iron. The strainer I use is
cup-shaped, with a flange round the edge, the flange having no holes in it.
The flange must fit close to the pot, and is fastened down by a flat ring of iron
exactly covering it, through which screws are fastened into the pot. The size
of the strainer is from six to eight inches in diameter, and the hollow of the
inside about one inch deep. The second strainer which is over the first is of
stouter iron and pierced with quarter inch holes. With this no ring is
necessary, the flange of the outer strainer being sufficient to take the screws.
This second strainer in some cases I do not employ. Underneath the hole in
the crystallizing pot is a spout or channel to carry off the lead as it runs out
of the pot into another pot set so as to receive what runs from the spout; this
spout is set in an opening made through the side wall of the fire hole
of the crystallizing pot, and the hole in the said pot must be so pierced that
the lead shall run out directly into the spout. To stop the hole in the
crystallizing pot I use a "tapping bar," that is to say, a bar of iron slightly
'taper at the end which is to stop the hole, and of such size as just to fill the
hole. This bar is driven gently into the hole and fixed by a blow from a
hammer; it may also be fastened in by a screw to prevent its being knocked

page_text: out accidentally. To begin the separation the tapping bar is fixed in the hole
so as to stop it, and the silver lead then melted down; when melted it is
cooled with constant stirring as in the ordinary process, but the stirring and
cooling are continued much longer than in the ordinary process. The stirring
should be continued so long as the stirrer can be got through the crystals, if
the least possible quantity of liquid lead is wanted to be drawn off, but the
length of time during which the stirring must be continued depends upon the
quantity of crystals wanted. As soon as the desired quantity of crystals is
formed, which is known by the thickness of the mixture of fluid lead and
crystals, the tapping bar is withdrawn, and the fluid rich lead run off, the
crystals being allowed to drain as long as any fluid lead runs from them. The
fluid rich lead being all run off the tapping bar is replaced, the poor crystals
remelted, and the operation repeated as desired. In case the hole be stopped
up with crystals or cold lead, I use a red hot bar of iron which melts the lead
closing the hole, and lets the fluid lead and silver escape. I also sometimes
put a small quantity of hot coals or burning wood in the spout under the hole,
so as to heat it if necessary. By this process the rich lead is obtained in the
lower pot, while the crystals of poor lead are left in the original crystallizing
pot. Instead of stirring by hand with a slice as is usually done, I in some
cases use a mechanical stirrer, consisting of an upright shaft connected by
gearing or otherwise with a steam engine, water wheel, or other source of
power, so that it is turned around by the said power. This upright shaft is
fixed in the centre of the crystallizing pot, with a bearing at top and bottom,
and carries arms radiating from it extending to the sides of the crystallizing pot.
The shape and number of these arms is not very material, but I prefer flat
arms with a thin edge foremost, and inclined so that the front edge is lower
than the back.
In witness whereof, I, tho said Philip John Worsley, have hereunto set
my hand and seal, this Third day of July in the year of our Lord One
thousand eight hundred and sixty.
PHILIP JOHN WORSLEY. (L.S.).