M Francon, N Krauzman, J P Mathieu and M May London: Gordon and Breach 1970 pp xii + 211 price £5 The field of physical optics lends itself to demonstration experiments more readily than perhaps any other branch of science. In view of the current tendency to stress mathematical formalisms at the expense of observation of phenomena in our physics courses, it is to be specially welcomed that a group of distinguished workers in the field of physical optics have taken the trouble to collect in book form their experience in setting up class and lecture demonstrations.