The Stress in Magnetised Iron

Abstract

MR. WILBERFORCE'S letter (NATURE p. 462) raises some points I ought to notice. In treating of the stress and strain, my phraseology has, I think, been extremely “unmaterialistic,” in the sense that I have said little or nothing about a magnetic “ether,” and have employed rather the language of action at a distance. Maxwell doubtless would have put things very differently, but my own experience has been that when one wishes to avoid confusing ordinary people on such questions as the sign of a stress or strain, the less one says about “ether” the better. My discussion of Maxwell's electrostatic medium (Proceedings Edinburgh Math. Soc, vol. xi. p. 107) will show, I hope, that his standpoint is not unfamiliar to me. The question really at issue is the existence and sign of certain strains in iron and other gross materials, and I judged Prof. Ewing's mode of presenting the case, which I practically followed, to be as clear as any. If strict Maxwellians object to the association of his name—which I did not originate—with stresses answering to the strains in question, by all means let us use another term, say “Q stresses,” so long as their existence is queried.