The change in intensity of fluorescence of ZnSiO3, CaWO4, CdB2O5, was measured at various temperatures between room temperature and the temperature of liquid oxygen. The fluorescence was excited by means of the 2537 Å line of a mercury arc. Microphotometric measurements were made on photographs of the fluorescent spectra. The results indicate a decrease in intensity with decrease in temperature of the CdB2O5 and the fluorescence of ZnSiO3 passes through a maximum of intensity between room temperature and liquid oxygen temperature
