AN IMPROVED PROCESS AND MACHINERY FOR EXTRACTING GOLD FROM AURIFEROUS DEPOSITS
Year: 1880

page_text: PROVISIONAL SPECIFICATION left by William Robert Lake at the Office
of the Commissioners of Patents on the 22nd December 1880. A communi-
cation from abroad by Ozias Bailey, of Whitecloud, Kansas, United States of
America.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent
Agents, Southampton Buildings, London. "AN IMPROVED PROCESS AND
MACHINERY FOR EXTRACTING GOLD FROM AURIFEROUS DEPOSITS." A commu-
nication from abroad by Ozias Bailey, of Whitecloud, Kansas, United States of
America.
This Invention relates to an improved process and machinery or apparatus for
separating gold from auriferous deposits.
In carrying the said Invention into practice I employ a tank, which is kept
nearly full of water, and a long box made of iron or other suitable material having
The screen
a curved bottom composed of grating covered with screen-wire.
thereby formed is composed of sections of different degrees of fineness, the finest
being at the bottom of the said screen where the earth is thrown in and the
coarsest at the upper end thereof, each upper section being coarser than that next
below. This box when in position is at an angle of about fifteen degrees to a
borizontal plane and is located within the aforesaid tank.
An axle or shaft having its bearings in the ends of the said box and arranged
parallel to its bottom projects through the lower end of the box and carries a
sprocket wheel, by means of which it is rotated. The said shaft is provided from
end to end with a single row of stirrers or blades set at short intervals apart in the
form of a screw; these stirrers carry the tailings or refuse to the upper end of the
box, whence they are discharged, the finer earth and precious metals falling through
the screen into the bottom of the tank. These grinders or stirrers are bevelled in such
a manner that they tend to assist the screw to carry the dirt up and to more
thoroughly mix and grind the same, and there are set in the said shaft as many
straight grinders as may be required and in positions not interfering with the action
of the screw-grinder.
A screw conveyor is arranged longitudinally in the bottom of the tank for the
purpose of conveying its contents, which consist of auriferous earth of the consistency
of slush to an elevator working at its lower end in a well into which the slush is

page_text: discharged by the screw conveyor. This elevator extends vertically upward a
sufficient distance to empty its contents into a chute, which conducts the slush into
an upright or vertical tank, having attached to its opposite sides a series of
amalgam plates arranged on an incline and forming a zigzag passage from top to
the bottom of said tank. At the bottom of this tank is a well, provided with a
series of pockets filled with mercury or quicksilver, which will arrest any coarse or
shot gold that may pass down over the amalgamated plates. From the said tank
the slush passes through an outlet above the quicksilver-pockets into a horizontal
tank also provided with amalgam plates.
A valve or stop-cock is arranged at the lower end of the vertical tank so that it
may be adjusted in such a manner as to govern the outflow from the same into the
horizontal tank and thus at will regulate the quantity of liquid slush within the
said vertical tank. The passage-way for the slush through the horizontal tank is
V-shaped in cross-section, and is in the form of a zigzag from side to side. The
walls of this zigzag or angular passage may also be covered with amalgamated
plates from end to end, and the bottom of the tank is provided with pockets, as
above stated, for the reception of quicksilver, so that any gold passing through
this chamber cannot fail to be arrested.
The said vertical and horizontal tanks may be used together or separately as
desired.
To facilitate the washing and perfect the separation of the auriferous from the
earthy particles I apply in the tanks atmospheric pressure with a view to agitating
the slush as follows, that is to say:-At right angles to the horizontal tank is a
frame supporting a double acting bellows or other blower. From the nozzle of this
bellows or blower extends an air-conduit or pipe, which passes along the top of the
said tank from end to end. To this air conduit or pipe are connected tap-pipes
arranged at an angle to the said pipe corresponding to the branches of the
zigzag passage way, one of the said tap pipes being over each of said branches.
Depending from the tap pipes and arranged at short intervals are a series of
distributing pipes, which extend downward nearly to the bottom of the said
angular passage way, and they are bent toward the discharge end of the latter.
When power is applied to the blower there is a constant volume of compressed air
discharged in jets from the distributing pipes, which now agitates the slush and
forces it toward the discharge end of the tank, and the commotion thus created
forces every particle of the slush into contact with the amalgamated plates and
quicksilver, to which the gold will adhere and thus be saved.
Atmospheric agitation is produced in the upright tank by means of a main
air-pipe connected to the blower and outside of and extending down to a point
near the bottom of the said tank and below the lowest plate, where it is provided
with a distributing rose perforated with numerous holes on its underside so that it
may not become choked up with sand. The air forced by the blower through the
rose rises to the top of the tank and creates in its zigzag course through the
labyrinthine passage formed by the amalgamated plates a violent bubbling and
agitation of the slush, thus greatly expediting the deposition of gold-dust upon the
said plates.
From the horizontal tank the slush is delivered into a well at its outlet end,
from which the sediment is scooped up by the buckets of an elevator and dropped
upon an endless apron and conveyed to a suitable dumping-place. The
elevator-buckets have wire gauge bottoms, through which the water trickles back
into the said well. This well, if water be scarce, or if for other reasons it be
deemed requisite, may have an overflow-pipe discharging the water into a suitable
cistern or receptacle, whence it may be pumped and used again and again.
Motion is imparted to all parts of the machine requiring motion from a
line shaft by means of sprocket wheels and endless chains, the former being keyed
upon the said shaft and on the journals of the working parts. I prefer for this
purpose the following arrangement, that is to say :-I provide a sprocket wheel on
the journal of the screw-shaft in the aforesaid long box and a similar wheel on the

page_text: liue shaft, around which passes an endless chain. Another sprocket wheel is
arranged on the journal of the conveyor and a corresponding one on the screw-shaft
around which an endless belt is also passed. Two other sprocket wheels are
arranged on the upper shaft of the elevator and the line shaft are also connected
by an endless belt. Thus the rotation of the line shaft actuates the screw-grinder
and conveyor, and through a crank upon its end and a pitman actuates a pump
which supplies the box with water. A sprocket wheel is also arranged on the
upper shaft of the elevator, which scoops up the sediment from the horizontal tank
and a similar wheel on the line shaft. These wheels are also connected by an
endless chain. Similar wheels are arranged on the shaft of the endless apron and
the line-shaft, and are also connected by an endless chain. Sprocket wheels are
fitted upon a short shaft journalled in the frame above the bellows or blower, and
connected with a sprocket wheel on the line shaft and a similar wheel upon the
shaft or drum of the endless apron. Thus all the moving parts of the machine
receive motion from the line shaft, which derives power from a motor through
suitable connections.
When a bellows is used to produce the air-blasts it is provided with a central
partition and a nozzle having two ports, one of the said ports being arranged in
connection with each division of the bellows, and each division having its own
valve, so that while one division is expelling air through its port the other is
taking air in. Thus a constant and unfailing air-current is kept up with no
danger of back suction through the nozzle, which sometimes occurs in single acting
bellows.