In the Furness district, the iron-ore produced is, except as to a small percentage, sufficiently clean when sent out of the mines to permit of its being taken direct from the pits to the smelting-furnaces, with no other dressing than the picking out of any lumps of clay or stone that may be seen when the ore is tipped from the small mine-waggons into the railway-waggons. In some of the deposits of the district, however, a small proportion of the ore is so mixed with sand and clay as to make it necessary to submit it to a process of washing before sending it to the furnaces, and certain portions of the Park deposit are of this description. The writer proposes to describe briefly the process adopted for washing such ore.

The separation of the impure portions of the ore, from the good, takes place in the underground workings, and the impure ore is sent out of the pit as "washer-ore," and carried direct to a common depot near the washer. This depot consists of a series of hoppers into which the ore is tipped, and whence it is run into small waggons or bogeys which are taken up an incline-tramway to the uppermost floor of the washing shed by means of an endless wire-rope.

At this point, the process of disintegrating and washing the ore begins. The ore is tipped slowly into a Blake stone-breaker, and a stream of water is passed with the ore between the jaws to assist it through. The action of the stone-breaker is to crush the clayey lumps and make their after-disintegration easier.

From the breaker, the ore, along with a stream of water, drops into a trough in which revolves a shaft furnished with cast-steel blades or cutters, which help to break up the clayey lumps and secure a regular feed to the revolving-drum, into which the ore next passes by means of a feeding-chute. The revolving-drum is the essential part of the washing machinery. It is a tube made of boiler-plate, 19 feet long and 4½ feet in diameter, furnished on the inside with a double-threaded screw or worm made of 3 inches angle-iron, riveted to the drum at a pitch of 20 inches. The spaces between the threads of the screw are furnished with spikes, also riveted to the drum. The intake-end of the drum is narrowed by means of an end-plate to 2 feet 4 inches in diameter, and the last 4 feet of the discharge-end of the drum is perforated with inch holes. The drum is carried on two sets of rollers travelling in steel rings riveted on to the body of the drum, which is made to revolve by cogwheel gearing at a speed of 9 revolutions per minute. The drum is placed slightly on an incline, the discharge-end being elevated 19 inches above the intake-end. A powerful stream of water is supplied near the discharge-end, and flows out underneath the feeding-chute at the intake end. The action of the drum is to roll, disintegrate, and travel the material forward in the midst of the flowing water, which, passing out of the narrowed end of the drum, carries along with it the finer portions of the sand and clay which have now become reduced to a slime.

As the washed ore approaches the discharge-end of the drum, it traverses the perforated space, and is there subjected to a riddling process. What passes through the holes goes off to the jiggers, and the rougher portion is discharged on to a reciprocating picking-table, where any stones and unreduced clayey lumps are picked out, and the cleaned ore drops from the picking-table into railway-waggons. The unreduced clayey lumps are dropped into a disintegrator, which is placed underneath the picking-table, and the discharge of this disintegrator is elevated to the intake-end of the revolving-drum to go again through the washing process.

The material to be jigged is a mixed mass consisting of good ore and numerous pieces of quartz containing a percentage of iron, but far too high in silica to be of any value for smelting, and the object of jigging is to throw off these particles of quartz and other impurities. For jigging purposes the material is classified into seven different sizes, and each size is dealt with by a separate jigger. The separation into the first four sizes is effected by means of revolving trommels or perforated drums, 4 feet lung and 23 inches in diameter with 3/8, ¼ 3/16, and inch holes respectively the finer sizes are separated out by means of pointed boxes supplied with a jet of water, and attached to the bottom of a trough along which the fine material is made to flow.

The jiggers are of the ordinary piston or pulsating type and have three compartments in each. The jigger-sieves are made of perforated plates, the holes in the plates supplied to each jigger corresponding with the different sizes of the material that has to be dealt with. The good ore from the jiggers is made to discharge into tanks, and is then raised by elevators to a sufficient height to fall into the railway-waggons.

The very fine material which passes beyond the jiggers is conveyed to a propeller-buddle, which consists of a revolving shaft furnished with iron arms, at the end of which are fixed thin iron blades which traverse the material sideways along a sloping surface, down which flows a stream of water carrying off the impurities.

The whole of the machinery is operated by a semi-portable Roby engine with a cylinder 11 inches in diameter and 16 inches stroke. The several parts of the machinery are brought into connexion by means of belts and pulley-wheels and cog-wheel gearing. The quantity of material that can be dealt with in a day of 9 working hours is about 110 tons.

The quantity of water supplied to the different parts of the machinery amounts to about 400 gallons per minute.

The waste from the washer is all concentrated in a discharge-trough, the rougher portions are extracted by passing the water through watertight bogeys, which, when full, are tipped on to a waste-heap, and the finer portion of the waste is taken to the sea along a line of troughs.

The photographs supplied will help to illustrate the principal parts of the machinery,

The average working cost (excluding renewals to machinery) is 10.81d. per ton of clean ore delivered.

The average percentage of clean ore is 64.42 per cent. of the "washer-ore" put in, showing that there is 35.58 per cent. of waste stone removed in the washing process.

The Chairman (Mr. J. L. Hedley) proposed a vote of thanks to Mr. Kellett for his description of the ore-washing plant, which the members were to inspect.

The vote of thanks was cordially adopted.