PROF. SODDY has directed the attention of readers of NATURE (November 4, p. 310) to the issue on the part of the War Office of a letter in which the active co-operation of men of science is invited towards the intensive development of chemical warfare. The list of ordinary associate members embraces more than sixty names of chemists, physicists, and medical men—a list apparently drawn up without consultation with the various members concerned. On receipt of the letter referred to, I replied at once with the request that my name should be removed from the list of associate members, and in this refusal to serve I was actuated by the following considerations: