MENTS IN REDUCING METALLIC ORES
Year: 1854

page_text: by the Act.)
PROVISIONAL SPECIFICATION left by Paul Rapsey Hodge at the
Office of the Commissioners of Patents, with his Petition, on the 20th
March 1854.
I, PAUL RAPSEY HODGE, of Moorgate Street, in the City of London, Civil
Engineer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN REDUCING METALLIC ORES" to be as follows:-
The process of reduction of metallic ores consists usually in crushing or
grinding the same, and separating the metals from the dross by means of
water, and when the ores contain the precious metals the process is continued
to amalgamation with mercury, and to delivering the precious metals from the
mercury.
My improvements in this process consist in the new form of a machine or
vessel, in which I crush ores with a ball or balls, such form giving great facility
for clearing the machine of its contents when crushed; the power of unship-
ping or taking out the balls and replacing them, the saving of wear and tear
of the balls and surface of the machine against which the balls rub, the flow
of water to the ores, and the heating of the contents of the machine when
mercury is used; they also consist in the apparatus I provide, in connection
with the machine, for receiving the tailings of ores containing grains or parti-

page_text: cles of the precious metals, as such tailings pass from the machine, and in the
apparatus in which I place the amalgam of mercury and metals taken from
the machine, to distil and recover the mercury and separate the metals. The
whole of these improvements form portions of the one process of reducing ores
when they contain particles of gold or silver.
The machine I use is of a dish or vaseous form, with a large mouth,
revolving on a hollow axis or shaft fixed to the machine at the opposite side to
its mouth; through this axis it is fed with water. Balls are placed within the
machine, and when fed with ores and set in motion the ores are crushed by
the balls. The machine, in its attachment to the axis which causes it to
revolve, is so constructed as to permit of its being disengaged and tilted
sufficiently to allow the balls to roll out at the mouth of the machine, and
when thus tilted to have the balls replaced in it; also, mechanical contrivances
have been provided and invented by me to keep up a variable axis in the
machine, so as to change the impinging point of the balls at every revolution,
either right or left. Also apparatus can be attached to, the machine, consisting
of: annular, pipes surrounding the machine or vessel, to be heated by hot. water
or steam, by which the ores and mercury are heated while being crushed and
rubbed together. The tailings from this machine are received upon a series of
'tables or surfaces placed in connection with the machine, covered with goat,
sheep, or other animal skins, with the hair or wool uppermost, cut close and
uniform, not exceeding an inch in length. The gold and silver atoms or
particles, in the tailings are caught or arrested upon. these surfaces. The
amalgam of mercury and precious metals obtained from the machine I place
in an apparatus constructed as follows:-The apparatus consists of a retort
and internal cup for holding the amalgam, and a traversing cistern with water,
so that the surface of the water may be brought within a few inches of the
amalgam, so placed as to have the mercury evolved and condensed. By this
method of distillation the vapour of mercury has not to be forced, as it usually
is, in a vertical column, but descends by its own gravity, and is immediately
condensed. I do not claim as new the crushing of ores by means of balls or by
a machine revolving, nor, do I claim the heating of the ores and mercury while
being rubbed together, all which operations in the process of reducing ores are
-well known in Great Britain, and have long been in use in the United States
and elsewhere, nor do I claim the separation of mercury from the metals by
distillation. I claim only the general form and arrangement of and methods
of working my machine, in combination for crushing and amalgamation, with
its novel adaptations or mechanical contrivances, as before described, for tilting

page_text: the same and unshipping and replacing the balls, and for changing periodically
the points or lines of contact between the balls and inner surface of the
machine when grinding; and I claim the use or application in connection
with the said or any like machine of tables or surfaces of shorn goat, sheep,
or other skins to receive the tailings coming from such a machine; and I
claim the particular form and combination of parts in connection with such
traversing cistern as aforesaid for an apparatus for distilling the mercury from
the amalgam, by which the advantages are obtained of recovering all the
mercury, and preventing any fumes escaping deleterious to the health of the
operators.