ABSTRACT
Lecture demonstrations are held by most physicists to be good in principle but too much trouble in practice. Eric Rogers was one of the relatively few physicists prepared to take the time and trouble to demonstrate often and well. Sir Lawrence Bragg, writing about the famous Christmas Lectures at the Royal Institution in London, says:
It is surprising how often people in all walks of life own that their interest in science was first aroused by attending one of these courses when they were young, and in recalling their impressions they almost invariably say not ‘we were told' but ‘we were shown this or that.
