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Xto the stamps V, to be further pulverised. The finer and lighter particles flow with the water over a partition into a sludge-pit, in which the sludge-band b moves slowly in the direction of the flow of the water, scraping together the fine sludge and depositing it in the pit Q. The elevator c conveys the sludge to the grader P, or, if the sludge is of no value, it may be at once removed. " The greater part of the water after settlement is raised by the rotary pump c to be used over again. " The rollers T T 1 T 2 serve for crushing not only products from the sizing drums, but also such products from the washers LL 1 L 2 as require further treatment. The number of sets of rollers, drums, and washers may be varied according to the character of the material treated. " The ore which has been crushed and pulverised in the stamps is separated into several sizes by means of the revolving-drums /, f l , f'\ f 3 (communicating with one another by g, g l , g 2 , g !> ), and led by spouts h, h l , h 2 , h? into washers p, p l , p 2 , p 3 , whence from time to time the concentrated ore is removed, the water passing by the troughs q, q l , q 2 , q s , q i , to a channel leading into sludge-pit Q. The material that passes through the meshes of the dram / 3 is graded in a series of gragers j, which feed suitable percussion-tables or other known apparatus for concentrating slimes. " Having now particularly described and ascertained the nature of our said invention, and in what manner the same is to be performed, we declare that what we claim is: — " The apparatus for dressing ore, placed in successive stories of a building with suitable elevators and shoots, so arranged that the ore raised to the upper story is dealt with as it descends, by crushing, stamping, grading, washing, and otherwise, as set forth, so as to separate the rich or metalliferous portions for subsequent treatment. " Dated this 16th day of October, 1890. " Carl Luhrig. " John Charles Cunninghame." " Certified to be a true copy.—Whitaker and Russell, solicitors in New Zealand for the applicants."

" Specification.—Concentrating Machinery. " Improvements in Apparatus for Washing, Separating, and Concentrating Ores of different Specific Gravities. " We, Carl Luhrig, of Dresden, Saxony, German Empire, Engineer, and John Charles Cunninghame, of 127, St. Vincent Street, Glasgow, Scotland, Iron and Coal Master, do hereby declare the nature of our invention for improvements in apparatus for washing, separating, and concentrating ores of different specific gravities, and in what manner the same is to be performed, to be particularly described and ascertained in and by the following statement : — " This invention has for its object improvements in apparatus known as percussion-tables for treating ores and similar substances in a pulverised state, by which the ore is separated or classified according to specific gravity, and each class is caused to pass into a separate trough as it leaves the table. " This invention also relates to an arrangement of several sets of the apparatus in such a manner that the pulverised ore washed from one table, or from one set of tables, in a partially separated or classified condition, can be passed over another table or another set of tables to be similarly operated upon for more complete separation or classification, and finally delivered into receptacles without requiring manual labour. " The improvements are illustrated by the accompanying drawings. Figs. 1, 2, 3, and 4 represent respectively a plan, a side sectional elevation, an end sectional elevation, and an end elevation of a single percussion table. Fig. 5, sheet 2, is a part sectional end elevation showing an arrangement of several percussion-tables in combination. " Referring first to Figs. 1, 2, 3, and 4, the liquid holding the minerals in suspension is supplied to the feeding-box A, which, according to this invention, instead of being stationary, as attached to the movable frame so as to move to and fro with it. From A the liquid passes over the distributingtable Bon to the indiarubber band C. In order to cause the liquid to flow gradually on to Git is preferred to fix to the edge of B a strip of calico or other fabric, which rests loosely on, but in contact with G. To insure that the rubber band C shall retain its position upon the roller D, short strips of wood E are attached to its outer surface and placed in a row, so that as the band travels they pass along an inverted channel iron F, which is fixed above the table. The guide-rollers G under the table are recessed to allow passage of the strips E. The friction of the band Con the table may be reduced by making a number of diagonal cuts across the table 4H"for the free passage of water supplied by a spout I and gutter J, so that there is a film of water interposed between band C and the table. Water flows on to the band C from the trough Kby a pipe L extending diagonally across the table with a series of nozzles 1, 2, 3, 4, 5 for jets of water to remove adhesive matter from the rubber. The percussion action imparted in the usual way to the table separates the particles of mineral into several —usually three—different classes according to their respective gravities. The lightest collect on the band C, and are delivered by the hopper M into the receptical N, an intermediate product is delivered by P into Q, and the heavier by B into S. " As shown by Fig. 5, six single tables are combined so as to constitute a compound machine, so arranged that the lower sets of the apparatus can be fed by gravity from the upper sets without requiring any manipulation of the material treated. * Although six tables are shown in Fig. 5, obviously a greater or less number might be thus arranged. " Assuming that there are only three—namely, the uppermost three as shown in Fig. 5, they may be worked as follows : The material fed to the uppermost table is separated into three classes, according to gravity as above described. The lightest may be allowed to flow to the table on the right, the intermediate quality to the table on the left, while the heaviest may be discharged as final products, or the products from each table may be discharged or treated in others of the table according to their character. The three tables are all connected to one motor, so as to work together.