Intersecting Rib-marks on Glass

JSGT 1951 V35 T041-T042

This is a brief note to indicate our concurrence in the view that “Wallner's lines” are an effect of the passage of transverse (“shake”) wave across the head of an advancing fissure. This interpretation was first called to my attention, I believe, by E. F. Poncelet about 1945, when he was working at this laboratory on these phenomena. The details have been elegantly worked out by Prof. Adolf Smekal, who showed us much of his work on his visit here in 1949, and some of it has since been published in the Glastechnische Berichte.

F. W. Preston