Abstract: A separation vessel (10) for separating materials of different densities comprising a chamber (14) having an external periphery (20A) at least part thereof which progressively increases from one section to another section. A mixture of materials of different densities enters the chamber (14) through an inlet (13) and travels in a spiralling vortex progressively outwardly to the widest section of the chamber (14). A primary exit (17) for material of greater density is provided closely adjacent to the widest section. A secondary exit (16) for material of lesser density is also provided.

Abstract: A seed sower is provided having an apertured driven pick-up member which has spaced apertures in its periphery in communication with a suction member. The apertures are moved through seed storage means so that single seeds are picked up by the pick-up member by suction and held over each aperture. The seeds are carried to a discharge locality and released for planting. The pick-up member is hollow and has an internal sealing member which contacts each spaced aperture adjacent to the discharge locality thereby sealing off the suction and allowing each seed to travel to the discharge locality.