In addition to the formation of the sheet, the production of multi-coloured calendered linoleum of desired pattern is dependent on the plastic flow of the unseasoned material. By extruding the unseasoned linoleum mix in the apparatus described, its behaviour under calendering conditions and the effect exerted by the conventional fillers (cork, wood flour, and whiting) can be demonstrated with curves showing extrusion rates at different temperatures. A relationship is derived between the volumes of the different fillers required to give linoleum mixes of the same flow characteristics, and this relationship holds over a wide range of temperature and rate of extrusion. A few curves obtained with the apparatus for allied floorcoverings, e.g. asphalt tile and P.V.C. flooring are also given.