jigging or moving to-and-fro in or approximately in the direction of conveyance

Full Title

Sieving, screening, sifting, or sorting solid materials using networks, gratings, grids, or the like > Moving screens not otherwise provided for, e.g. swinging, reciprocating, rocking, tilting or wobbling screens > jigging or moving to-and-fro in or approximately in the direction of conveyance