Depth absorbed dose distributions for electrons

The communication by Atherton and Coleman (see ibid., vol.20, p.658, of 1975), based on a comparison of the author's depth absorbed dose distributions measured with a liquid ionization chamber (see ibid., vol.20, p.39 of 1975) with their measurements of the distribution of the radiation-induced current in a silicon diode is commented on. It is thought that the comparisons presented in their correspondence are to a great extent misleading both because they have used a different method of dosimetry and because they have compared a clinical microtron beam (with scatterer and applicator etc) with a linear accelerator beam of little clinical use (without scatterer and applicator).