[1746]. Tub and paddle washer.

[Larger plate.]

[1747]. Coal washer. The water is kept in motion up and down through the screen A by a cylinder and piston B; the mud sinks to C and the washed coal passes over to D. Both are removed continuously by elevators or worms. See [Section 57].

For washing ores sloping screens either plain or perforated are often used, a stream of water being kept flowing over the ore, which is kept in motion. See [Nos. 1266] and [477], also Cylindrical Revolving Screens, as [No. 1262].

[1748]. Cylindrical perforated drum, with internal fixed spiral flange which causes the material to travel at a fixed rate of motion. The cylinder may be revolved in a water trough as [No. 1745], or water may be fed in with the material and the casing be unperforated.

[1749]. A contrivance to keep a continuous circulation in a boiling tub or copper in which clothes, &c., are washed. The hot water from the bottom rises up the tin tube, and is discharged on the surface.

[1750]. Corrugated rollers washing device, for fabrics.

[1751]. Water trough and dipping band, for washing cloths, wool, paper, &c.

Domestic washers comprise, besides the ordinary tub and dolly, washing boards, having corrugated surfaces; rocking and revolving boxes, having a churn-like motion. Brushes also are sometimes used.