A method of manufacturing an optical fiber base material having very little impurity which deteriorates the transmission characteristic of an optical fiber is provided. Also disclosed are methods for making a lipid matrix of lysophosphatidylcholine, monoglyceride and fatty acid, and lipid matrices of particular structure. For zooming, the first positive lens unit is stationary, the first negative lens unit moves, and the second positive lens unit moves. The telescoping shaft is mechanically coupled to a water intake. The machine base affords a plurality of mounting points arranged symmetrically on either side of a vertical median plane, passing longitudinally through the base, so that the position of the feed unit can be reversed in mirror image relative to the median plane, as also can the positions of the first folding and closing assembly and the second folding and closing assembly. A set of identifier values are used for identifying signalling links allocated in advance to signalling links between adjacent signalling points.