Letter from W W C [William Whiteman Carlton] Topley to the Royal Society, regarding two papers, 'The action of radiations on bacteria. IV - the lethal action of soft X-rays' and 'The action of radiations on bacteria. V - the target theory', by R B Haines and D E Lea Paper reference code: B.68 and B.69 Unable to provide a full report on the two papers. His only comment is that the methods of counting used by the authors are subject to large margins of error and it seems unreasonable to base conclusions on these. A more accurate method of counting ought to have been devised. [Not published]. Received 7 December 1938 6 December 1938