Abstract: The two stage gravity method of concentration of fine dry materials makes use of the differences in the specific gravity of the materials by using principles fairly similar to those used in wet shaking table. The dry materials are loaded in a continuous series of troughs as they pass successively underneath a loading means as they travel conveyor belt like in a close circuit and, as they travel they are firstly submitted to a series of cyclic directed shaking motions transversal to the troughs and secondly, to a series of similar cyclic shaking motions parallel to the long axis of the troughs, the whole resulting in the production of a concentrate, and of middlings and waste which are unloaded in suitable receivers as the troughs turn downward in their conveyor belt like circuit.

Abstract: A temporary transparent insulating installation is disclosed for mounting on the inside of a window frame. This installation provides for increased insulation of buildings without necessitating an increased number of glazings in a window. The installation comprises a clear plastic sheet with a length greater than the height of the window frame, having a first connecting strip along a top edge. The sheet has side edges with sealing means adapted to seal with two side surfaces of the window frame. The second connecting strip is permanently attached to the top surface of the window frame and is adapted to mate with the first connecting strip along the top edge of the plastic sheet. At least one weight is provided to hold down the plastic sheet on the bottom surface of the window frame. In another installation two or more clear plastic sheets can be hung in a window frame.