A NEW OR IMPROVED MACHINE OR APPARATUS FOR CRUSHING 'DIAMONDIFEROUS' SOIL FOR EXTRACTING DIAMONDS THEREFROM."
Year: 1877

page_text: PROVISIONAL SPECIFICATION left by Alfred von Doussa at the Office of the
Commissioners of Patents on the 9th August 1877.
ALFRED VON DOUSSA, of Kimberley Diamond Fields, in the Cape of Good Hope,
and at present of Cullum Street, in the City of London. "A NEW OR IMPROVED
MACHINE OR APPARATUS FOR CRUSHING 'DIAMONDIFEROUS' SOIL FOR EXTRACTING
DIAMONDS THEREFROM."
Hitherto the soil containing the diamonds after it has been dug from the mines
has had to be laid aside till dry, and then watered until it breaks up, when it is
then beaten with sticks by hand at different periods to break it up completely, so
as to prepare it for the washing machine, and consequently many weeks, and some-
times months, expire under these operations before all the diamonds can be extracted,
and these operations often gave rise to thefts.
Now the object of my Invention is to remedy these evils, and for this purpose I
construct a machine or apparatus for crushing the "diamondiferous" soil (matrix)
as soon as it is dug from the mines, and extracting the diamonds therefrom, no
matter what their size, and without breaking or otherwise damaging them, and by
the use of my machine or apparatus I am enabled to extract the diamonds in as
many hours as it formerly took weeks.
This machine or apparatus consists of a chamher case or receptacle which has a
moveable false bottom or bed plate, on to which the soil to be crushed falls. An
N shaped metal block or piece of triangular section is fixed to the moveable plate,
its object being to prevent the diamonds from being crushed by the stamper or
crusher as the soil is broken. The "diamondiferous" soil is placed in a hopper or
feeder from which it passes into the machine, and falls on to the N shaped block or
piece, and as this piece presents an edged surface to the crusher or stamper, the soil
is crushed without injury to the diamonds, which fall between its branches.
A constant supply of water is allowed to flow into the chamber during the
crushing operation, and causes the soil to assume a muddy consistency. As fresh
dry soil enters it pushes forward the wet or muddy soil to the front of the chamber,
which is fitted with a grating or netting, and through its openings or meshes the
wet or liquid soil of muddy consistency: containing small diamonds is forced to pass,
Price 211

page_text: From the grating or netting it falls on to an inclined table to which a shaking
movement is given by means of a steam engine or other prime mover. This table
has grooves, channels, or recesses formed in it, and the motion imparted to it causes
the diamonds with their accompanying heavy substances to quit the wet or liquid
soil, and to fall into the grooves from whence the sediment containing the diamonds
is collected, and the "tailings" or refuse is then carried away through sluices.
The side of the moveable bed plate or false bottom next the grating is bevelled,
so as to form a space for the reception of the heavy sediment containing those
diamonds which are too large to pass through the openings or meshes of the grating,
but when it be desired to remove this sediment with its diamonds the plate which
is so contrived can be drawn out; it is kept under lock and key so as to prevent the
diamonds being feloniously abstracted therefrom.
The stamper or crusher is connected to a rod which passes through the top of the
chamber, and terminates in a cam operated by a lever or beam, and worked by a
steam engine or other prime mover, the cam imparting to the stamper or crusher a
rotary movement as it descends on the soil, whereby it performs its crushing operation
more effectually.
Several of these machines or apparatus may be combined if desired and worked
together at the same time.