The Effect of Composition on the Viscosity of Glass

JSGT 1924 V08 T205-T251

IN a previous paper,* the results of an investigation on the viscosity of several series of glasses at temperatures ranging from the . annealing points upwards for 150° or 200° were presented and
discussed. The means of measurement then used, namely, the determination of the rate of elongation of standard-sized rods under definite loads, cannot be used at higher temperatures than those
already covered. The present investigation, using an entirely different type of apparatus, deals with the same series of glasses, but at temperatures extending from the highest points reached previously up to 1400°.

By S. ENGLISH, M.sc., A.I.C.
(Read at the Sheffield Meeting, May 29th, 1924.)