Lithium Oxide as a Constituent of Glasses‐its Effect Thermal Expansion*

Winkelmann and Schott give the factors of 10.0 to Na 2 O, 8.5 to K 2 O, and 2.0 to Li 2 O to indicate the effect of these oxides upon thermal expansion. A review of the literature of glasses containing Li 2 O and some measurements made on new glasses indicate that, in respect to thermal expansion, Li 2 O is as effective as Na 2 O in promoting high expansibility.