IMPROVEMENTS IN MACHINERY AND APPARATUS EMPLOYED IN WASHING DIAMONDS AND OTHER ANALOGOUS SUBSTANCES
Year: 1879

page_text: LETTERS PATENT to Thaine Allen, of 5, Copthall Court, in the City of London,
Civil Engineer, and James Noah Paxman, of Colchester, Essex, Engineer, for
the Invention of "IMPROVEMENTS IN MACHINERY AND APPARATUS EMPLOYED
IN WASHING DIAMONDS AND OTHER ANALOGOUS SUBSTANCES." Partly a com-
munication from abroad by Samuel Stonestreet, of Kimberley, Griqualand West.
PROVISIONAL SPECIFICATION left by the said Thaine Allen and James
Noah Paxman at the Office of the Commissioners of Patents on the 9th May
1879.
THAINE ALLEN, of 5, Copthall Court, in the City of London, Civil Engineer, and
JAMES NOAH PAXMAN, of Colchester, Essex, Engineer. "IMPROVEMENTS IN
MACHINERY AND APPARATUS EMPLOYED IN WASHING DIAMONDS AND OTHER
ANALOGOUS SUBSTANCES." [Partly a communication from abroad by Samuel
Stonestreet, of Kimberley, Griqualand West.]
This Invention relates to improvements in machinery and apparatus employed
in washing diamonds and other analogous substances, whereby an equable
distribution of "puddle" in the annular trough (hereinafter described) is obtained,
cleaning out the machine facilitated, and the loss of diamonds which so often occurs
in the ordinary rotary machines rendered impossible.
A hollow cone, hereinafter called the "umbrella," made of wood or other suitable
material, is fixed to a vertical shaft vertex upwards, the axis of the shaft being
coincident with the axis of the cone. On the end of the shaft which protrudes
above the vertex umbrella is a hopper, hereinafter called the "supply hopper."
From the lower end of the shaft and at right angles to it radiate a number of
arms, on each of which vertical knives are placed at intervals. The extremities of
these arms are supported by being fixed to the rim of the cone or umbrella herein-
before mentioned.
The shaft is supported by framework and bearings, and revolves on its vertical
axis together with the "supply hopper," umbrella, and arms.
The arms revolve in an annular trough the base of which is an inverted cone,
the annular trough being coaxial with the upright shaft.

page_text: The annular trough is supported by the framework. The conical base of the
annular trough is not continued to its vertex. A frustrum is removed, and in its
place is an overflow hopper.
Instead of the cone or "umbrella" first described we may have a number of flat
shoots each communicating at one end with the supply hopper, and having the
other end attached to an annular ring. In this case the extremities of the hori-
zontal arms are attached to this annular ring, instead of to the rim umbrella.
The machine is used as follows:-
The diamondiferous soil is first broken up, and with the addition of water passed
through a circular puddler and sieve or riddle, which separates and prevents all
large pieces of rock or stone passing into the machine, the puddle then flows
through a supply shoot into the supply hopper.
From the supply hopper the puddle flows down the surface of the cone or flat
shoots (as the case may be), thence dropping into the annular trough where by
specific gravity and centrifugal force the heavy particles such as iron, stone, pyrites,
ilmenite, diamond, and garnet are retained in the machine, and the lighter portions
of the puddle such as inud, sand, gravel, etc., flow over the edge of the overflow
hopper.
The above is a general description of the machinery and apparatus, but our
improvements are obtained by means of the umbrella or flat shoots being applied
in combination with the annular trough with the circular.base as above described.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thaine Allen and James Noah Paxman in the Great Seal Patent
Office on the 8th November 1879.
THAINE ALLEN, of 5, Copthall Court, in the City of London, Civil Engineer,
and JAMES NOAH PAXMAN, of Colchester, Essex, Engineer. "IMPROVEMENTS IN
MACHINERY AND APPARATUS EMPLOYED IN WASHING DIAMONDS AND OTHER
ANALAGOUS SUBSTANCES."
Our Invention relates to improvements in machinery and apparatus employed in
washing diamonds and other analagous substances, whereby an equable distribution
of the diamondiferous puddle in the tank or receiver is secured, cleaning out the
machine facilitated, and the loss of diamonds or other similar substances, which
often occurs in ordinary rotary washing machines, rendered impossible.
A hollow cone hereinafter called the "distributor" made of iron, steel, wood, or
other suitable material is fixed vertex upwards to a vertical shaft, the axis of which
is coincident with that of the cone. Fixed on the shaft and coaxial with it above
the distributor, but in connexion therewith, is a hopper, hereinafter called the
"supply hopper," baving outlet holes at its lower edge opening on the distributor.
The distributor may have on its upper surface a number of guides forming
channels from the outlets of the hopper to its own periphery.
The periphery or rim of the distributing cone is connected with the shaft by a
number of fixed radial arms at right angles to its axis, on each of which arms
vertical knives are fixed at intervals. The shaft which thus carries the distributing
cone and the radial arms fixed to it is supported by suitable framework and
bearings, and is provided with suitable gearing either to its upper or lower,
preferably at the upper end by which it may be caused to revolve.
The radial arms, and the knives, hereinafter called the "agitators," revolve in an
annular trough made in the shape of the frustrum of a cone, coaxial with the shaft
and supported by suitable framework. The bottom and sides of this trough are
made perfectly smooth without projecting rivets, bolts, joints, or anything to
interfere with the action of the agitating knives. The top of the frustrums has a
raised rim lower than the outer edge of the trough, and thus forms an inner
concentric overflow.
Instead of a conical distributor as hereinbefore described, we may have a number
of inclined shoots radiating from the outlets of the supply hopper to a curb ring,
to which ring the outer ends of the agitators are attached instead of to the
periphery of the base of the cone.
We may also construct the conical distributor or shoots without the supply
hopper herein before described, delivering the diamondiferous puddle directly on to
the apex of the cone.
In order clearly to explain the nature of our improvements, we refer to the
accompanying Drawings.
Drawing No. 1, Figure 1, is a plan of the apparatus shewing the distributing
cone A with its guides and the supply hopper C.
Figure 2 is a plan showing the substituted shoots A¹ herein before mentioned.
Figure 3 is a vertical section of the trough and distributor, and,-
Figure 4 is an elevation of the apparatus complete.
The diamondiferous or analagous soil having been broken up and reduced by the
addition of water and straining to a condition of puddle or slush is fed through a
supply shoot, Fig. 3, S, into the supply hopper C. This hopper together with the
distributor A and the agitators D is caused to revolve with the shaft B by power
applied through the gearing H. The puddle flows through the openings c, c, over
the cone A, or the shoots A¹, A¹, to the rim where it drops into the trough E,
and is thoroughly stirred by the agitators D, the knives of which are fixed spirally

page_text: on plan so as to scrape over the entire area of the bottom of the trough. By the
action of gravity and centrifugal force the heavy particles such as diamonds,
garnets, ilmenite, iron, and stone are retained in the trough, and the lighter
constituents of the puddle, such as mud, sand, or gravel flow inward and are
discharged by the overflow hopper G, whence they are removed by any convenient
ineans.
Drawing No. II. The same description and letters as in Drawing No. I., apply to
Drawing No. II., with the exception of the supply hopper C, which in Drawing
No. II, is omitted.
Having thus particularly described the apparatus or machine and the mannor in
which it is used, we now state our claims in our said Invention to be as follows,
viz.,―
1. The equable distribution of the puddle or material to be washed by allowing
it to flow over a cone or shoots to the outer circumference of an annular trough,
the said distribution being regulated by means of a concentric circular hopper fixed
at the apex of the said cone or shoots, and revolving with the said cone or shoots
as hereinbefore described and shown on Drawing No. I., annexed hereunto.
2. The equable distribution of the puddle or material to be washed by allowing
it to flow from a shoot directly over a cone or shoots to the outer circumference of
an annular trough, without the intervention of a concentric circular supply hopper,
as hereinbefore described and shewn in Drawing No. II., annexed hereunto.
3. The separation of the light and heavy components of the puddle in the trough
by means of the agitators hereinbefore described, and the removal of the light
components by means of a concentric central outlet, as hereinberore described and
shewn in Drawing No. I. and II., annexed hereunto.
In witness whereof, we, the said Thaine Allen and James Noah Paxman,
have hereunto set our hands and seals, this First day of November, in the
year of our Lord
THAINE ALLEN.
(L.S.)
Witness,
WM. H. LE FEVRE,
26, Budge Row,
City, E.C.
JAMES NOAH PAXMAN. (L.S.)