Abstract: A chair comprises a seat portion for enabling a user to sit on the chair and support means for supporting the seat portion. The seat portion is movable between a plurality of different height positions on the support means, and includes locking means adapted for engagement with and disengagement from the support means at each height position, by rocking the seat portion relative to the support means, wherein the seat portion is locked relative to the support means when the locking means is in the engaged position and free to move relative to the support means between different height positions when the locking means is disengaged.

Abstract: Furniture includes structure for supporting the furniture on a floor or like surface and includes structure for rotating the furniture about a predetermined vertical axis so as to prescribe a circular path. The furniture preferably includes rollers arranged at a predetermined orientation so that the furniture prescribes a predetermined circular path, on rotation of the furniture about the vertical axis.

Abstract: A floating platform is assembled from a number of square or rectangular modules. In the corner edges of the modules are slots adapted to receive link plates. Keys lock the plates to the modules by passing through bores in the modules and holes in the plates. The holes in the plates are shaped so that rotation of a key within a hole towards a locking position cams the plate further into its slot. Recesses are provided in walls of the modules to prevent water from spurting onto the surface of the platform when the modules are brought into abutment. Apparatus is provided around the edge of the platform for attaching posts and hinged ramps.