Abstract: A process and product therefrom for making a waterproof, durable and easily printed book with a plurality of pages of synthetic paper bound by water-insoluble adhesive or glue and/or water-resistant thread. A preferred embodiment is prepared with a series of depressions or wells into which water-insoluble adhesive or glue is introduced before the insertion of the pages therein, the pages being tightly bound together and to the cover backing by a combination of adhesive or glue and water-insoluble thread.

Abstract: An improved straight flow check valve construction is disclosed for use as intake and discharge valves in fluid compressors and other similar applications. The valve includes a valve inlet block and a valve outlet block which are attached together at generally planar abutting surfaces. A valve stop insert is positioned therebetween in a recess formed in the inlet block. At least one pair of valve ports extends through the inlet block, the valve stop insert and the outlet block and such ports are shaped to have elongated parallel cross sections in a plane perpendicular to the ports. Each port is closed by a separate valve plate. The valve plates for each pair of ports are mounted in the inlet block between the two ports for pivoting between closed and open positions and a single elongated V-shaped spring extends between the two valve plates for simultaneously biasing both valve plates to the closed positions. When the valve plates are in the open positions, the ports are streamlined.