Abstract: The land mine, comprises a flat mine housing having top and bottom flat broad surfaces and a side edge which is at least partly cylindrical. A tubular bushing extends in the housing between the top and bottom and it is closed on one of the surfaces by a cover. A firing system is located in the bushing for igniting an explosive charge which is contained in the remaining portion of the housing. Either or both of the top and bottom surfaces contain one or more projectile-forming hollow charge covers which engage directly over the explosive charge located within the housing. The mine may be formed with a half-cylindrical surface and a flat edge having a notch for engagement over a central mounting rod, or the mine may be made as a complete cylinder or disc. The hollow-charge liners are advantageously made circular and are arranged at one or more equally spaced locations around the surface of the top and bottom of the mine housing.

Abstract: Device for determining variations within an indicator tube having a material which varies in light intensity or color in the presence of particular gases, comprises a first set of light barrier devices as light sources and photoelectric cells on respective sides of the tube. A reference set of light barrier means is provided for sensing a reference value of light through the tube and is connected to a comparator for sensing the variations between it and the first set of light barrier tubes and for recording this information on a counter. The counters are connected to a time signal transmitter and time signal receiver and the predetermined variations which occur at various time intervals are picked up by an indicator or alarm circuit designed to show the variations and indications which are sensed in a particular time period.

Abstract: Direct cooling of melted thermoplastic resins, while in a continuous extruding operation, can be achieved, by pouring into them a coolant such as pure water, liquid nitrogen or the like in the cooling region of the continuous extruder so that the resins are directly cooled by the latent heat of the coolant or the temperature difference between the resins and the coolant.

Abstract: A fluid cooled rocket, comprises a tubular housing which forms an interior combustion chamber which has a closed end formed by a head containing a propellant component injector, and an opposite opened end forming a thrust gas discharge. The housing side walls define an interior combustion chamber of uniform diameter, adjacent the closed head, is formed into an inwardly converging portion, a nozzle neck portion of smallest diameter, and an outwardly diverging portion, all proceed in a direction from the closed end toward the opposite gas discharge open end.