IMPROVEMENTS IN OBTAINING SILVER FROM ORES AND THE MATTERS CONTAINING IT
Year: 1840

page_text: TODD, of Pindinnis Castle, Falmouth, Gentleman, 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-seventh day of July, in the fourth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the
said Francis Todd, Her especial licence, full power, sole privilege and
authority, that I, the said Francis Todd, my exors, adñiors, and assigns, or
such others as I, the said Francis Todd, 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, the Invention of "IMPROVEMENTS IN OBTAINING SILVER FROM ORES
AND THE MATTERS CONTAINING IT," communicated to me by a certain Foreigner
residing abroad; in which said Letters Patent is contained a proviso that I,
the said Francis Todd, shall cause a particular description of the nature of
the said Invention, and in what manner the same is to be performed, to be
inrolled in Her said 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
Francis Todd, do hereby declare the nature of the said Invention, and the

page_text: manner in which the same is to be performed, are fully described and ascer-
tained in and by the following statement thereof (that is to say) :-
The Invention relates to a mode of separating silver from such ores and
other matters which contain silver; and in order that the Invention may be
most fully understood and readily carried into effect, I will proceed to describe
the process as pursued by me. But I would first remark, that heretofore, when
treating such ores and other matters containing silver, it has been usual to
melt such matters in a reverberatory or other convenient furnace, and when
the matters were in a melted state, the same has been tapped of into a pit of
water, and is subsequently melted in another furnace and fused, and lead is
applied into the furnace and stirred into the mass, by which means, owing to
the high temperature of the furnace, much waste of lead took place.
Now the object of this Invention is, to melt the ores or other matters in a
suitable furnace, and then to tap the furnace and to cause the melted matters
from the furnace to be brought into contact with lead in a bath or baths of
melted lead conveniently placed for that purpose; and it is important, in
carrying out the Invention, that the fluid matters from the furnace should be
run into the bath of lead in comparatively small quantities, in order that every
part thereof, whilst highly heated, should come in contact with lead, and by the
affinities: of the silver and lead, to separate the silver from the materials with
which it was previously mixed, and the process of running the melted matters
into lead may be performed on first melting and skimming the same, or after
it has been treated as heretofore by cooling and after melting. And in
carrying out the Invention, I melt the ores or other matters containing silver
in the state as heretofore practised, or by any convenient furnace, and in an
open vessel (which I prefer to be of cast iron). Near to the furnace I keep
the lead to be used melted to receive the charge, and I have found that it is
desirable to draw off the melted matters from the furnace at intervals, stirring
the lead as the melted matters run into the same; and in tapping the furnace
I cause the stream of melted matter to be as flat or shallow as possible, in
order that the greatest extent of surface shall be offered to the melted lead as
the melted matters flow into it; and I may remark, that the quantity of lead
I use and keep melted for each charge of the furnace is at the rate of 600
grots to each 20 grots of the charge; and I have found that by running out
about two to 3 grot at a time from the furnace into the bath of melted lead,
and then letting it stand, that I am enabled most effectually to succeed. The
lead thus containing the silver is then to be treated in the same manner as
beretofore for obtaining the silver, which means are well known.
Having thus described the nature of the Invention, and given the best

page_text: information in my power, in order that the improvements may be readily
carried into effect, I would remark that I do not confine myself to the precise
means pointed out, so long as the Invention herein described be retained.
And I do declare, that what I claim as the Invention secured by the present
Letters Patent is, the mode of obtaining silver from ores and other matters
containing it, by causing such ores or other matters, when in a melted state, to
be run into a bath or baths of lead, as herein described.
In witness whereof, I, the said Francis Todd, have hereunto set my
hand and seal, this Twenty-seventh day of January, in the year of
our Lord One thousand eight hundred and forty-one.