Abstract: The invention relates generally to rotary hydraulic machines of the kind comprising, in a casing, a rotatably-mounted shaft and a plurality of cylinder-piston units mounted radially in star around the shaft and co-operating with eccentric means so arranged as to impart a relative movement to each of said units in turn, conjointly with the rotation of the shaft, and also with fluid-circulation means so arranged that each of the cylinder-piston units are supplied with fluid in turn. The eccentric means may comprise an eccentric bearing surface provided on said shaft and co-operating with the cylinder-piston units supplied with fluid through conduits formed in the shaft, under the control of a distribution ring engaged on the eccentric surface. The cylinders of the units are oscillatably mounted, and controlled retention means prevent any driving action on the distribution ring by the eccentric surface.

Abstract: Device for winding a cable on a drum in such manner as to form turns each comprising a circular portion extending over the major part of its circumference and connected to an adjacent turn by a short oblique portion, wherein the cable in the course of winding is guided by a cable guide member, means being provided to displace this member step-by-step along the drum in rotation, in such manner as to keep it stationary during the major part of each revolution of the drum and to displace it by one step over a distance equal to the diameter of the cable while the drum is completing its revolution.

Abstract: An apparatus of small dimensions may be used to operate the water contained in the processing baths of automatic processing machines. The solid residue may be collected and sent to silver recovery plants, whereas the evaporated water serves to heat the drying station of the processing machine whereinafter it may be fed to the washing station. In so doing, a considerable amount of wash water is recovered and no chemical compounds are discharged to the sewer through which pollution of surface waters is practically eliminated.

Abstract: Propylene is oligomerised in the presence of a boron trifluoride catalyst and a small amount of a reagent which reduces the activity of the catalyst, thereby resulting in a reduction of the average molecular weight of the oligomerisation product. Butadiene is one said reagent.