Properties of Soda-Baryta-Silica Glasses and Comparison with Corresponding.....
JSGT 1927 V11 T425-T432
Barium oxide is of much more modern introduction into glasses than lead oxide. Its extensive use for optical glasses was due to Schott, but it was certainly already in use as a constituent of glasses for pressed ware before Schott's work. For example, a glass stated in 1875 as being used at the works of Messrs. E. Moore & Co., South Shields, had the percentage composition: SiO2 74·1, PbO 0·86, CaO 2·88, BaO 5·16, Na2O 17·02, Al2O3,Fe2O3and MnO (combined) 0·58, SO3 0·28.
S. English & W. E. S. Turner