Abstract: Monolithic glass members are prepared by first hydrolyzing a solution of tetraethoxysilane in alcohol with an acid medium, and then gelating in a basic medium while using acid and base mediums to form compounds that volatilize during drying and sintering the gel. Substances, if any, which in the form of oxides can form a glass with SiO.sub.2, are added after hydrolyzing and prior to gelation.

Abstract: The invention provides a method of manufacturing a hollow metal light conductor in which at least one metal layer is provided on a core of a synthetic resin material, for example, polymethylmethacrylate, after which the core is removed, and a metal tube is formed. The core is preferably removed by slightly elongating the core so that the cross-section is reduced, after which the metal light conductor can be pulled from the core. The reflecting metal layer on the inside surface of the light conductor preferably is of aluminium. The invention provides a hollow metal light conductor, for example, for use in an optical spectrometer, which is also suitable in particular to be used for light having a short wavelength, to less than 200 nm.