A Note on Stress Systems and Photo-elastic Phenomena

JSGT 1927 V11_T023-T029

This note does not contain any material new to science: it frequently appears, however, that the subject is one of peculiar difficulty to most of those who would like to take an interest on the subject or to make use of photo-elastic phenomena in solving definite technical problems. The difficulty is apparently a composite of two difficulties: first, the difficulty of comprehending the exact relation between double-refraction and stress, which may be called the physics of the photo-elastic problem, and, secondly, the difficulty, more serious with most people, of visualising a whole stress system and recognising what is and what is not possible in such a system.

F. W. Preston