Abstract: There is disclosed an internal combustion engine within which is defined at least one cylinder accommodating a reciprocable piston, and within which is disposed a valve rotor mounted at the compression end of the or each said cylinder for rotation about the longitudinal axis of the cylinder and having a number of passages therethrough each extending between the cylinder interior and a portion of the structure having inlet and exhaust ports, to allow for conventional fourstroke operation with said valve rotor rotating at an appropriate fraction of crank-shaft speed, the construction being such that at top dead center following a compression stroke each passage forms a substantially independently enclosed combustion space at the compression end of the cylinder adjacent the crown of the piston.

Abstract: There is disclosed apparatus for the treatment of films of plastics material which comprises at least a basic unit having, in one section, grooved and heated roll means, and in another, following section, godet rolls. In use, films of fibrillatable plastics material, such as of polypropylene, which have been profiled to exhibit a plurality of parallel longitudinal enlarged portions, can be conveniently heated and hot-stretched, the grooved roll means being very effective for heating and traction purposes. The apparatus may include other units, and there may be additional sections in the basic unit, all preferably constructed on a modular system for cheapness and ease of assembly.

Abstract: Disclosed is a roll assembly for use in the profiling of film of plastics material. The assembly is characterized by conduits, passageways, and spaces, by means of which heating fluid may be fed to and removed from the assembly in a selective manner along the length of the assembly to facilitate differential heating. This is a very advantageous facility where, for any reason, operating conditions would otherwise give rise to uneven profiling.