Iron-Ore Concentration, No. 5. [Volume: 8, Issue: 6, 1890, pp. 349-353]

350

UNITED STATES ASSOCIATION OF

[VOL. 8,

sockets secured to the shaft, in place of securing the blades directly
to the shaft. The accompanying illustration shows an arrangement
of washer of which a number have been erected in central Pennsylvania, in Virginia, Tennessee, and Alabama, by the Gaysport
foundry, of Hollidaysburg, Pa. The ore as brought from the
workings is discharged from mine cars on a " grizzly " through which
all but the lumps pass into the trough. These lumps are fed into
a crusher and from this also drop into the trough, unless it is desired to ship them without washing. As, however, considerable
clay adheres to or is enclosed in the nodules of brown hematite
ore, the washing of the broken lumps is advisable. As the blades
cut or push the ore forward in the trough, it is met by a stream of
water and the clay is washed away, the ore passing out at the upper
end of the trough into a revolving screen in which a final rinsing
by water takes place, and in which the finer ore or sand is separated,
the coarse ore passing on to an inclined conveyor which serves as
a table from which any foreign material may be hand-picked.
In some instances all the fine ore which will pass through oneinch round holes is, after washing, treated in jigs, as described in
the JOURNAL, vol. viii., p. 42, when discussing the process used at
Iron Mountain, Missouri.
An advantage claimed for this washer is, that it embraces the principal feature of the submerged log-washers, logs being placed on an
incline of from two to three feet in their length, thus practically submerging the logs nearly one-half their length, the back-end of the
washer-box being 4 feet high. The logs are 17 to 18 inches in
diameter, and generally 30 feet long, covered with iron their entire
length. The teeth are made with detached bases, the bases being
secured to the logs so that the chilled teeth may be renewed without disturbing the bases. The logs are provided with flanged gudgeons, the back or lower gudgeon being protected with a chilled
thimble, which runs in a chill step or bearing.
The logs are both driven from the front or discharge-end by
spur and bevel-gearing. Two or more washers may be set side by
side, all driven by the same main-line shaft, with countershafts to
each washer, this countershaft being fitted with a shifting-clutch
so that any one machine may be readily stopped without interfering with the operation of the others.