'In 1934, the British journalist Wickham Steed, wrote a highly sensational article based on documents in his possession which he claimed had been extracted from the files of the German General Staff. These concerned experiments by German agents with non-pathogenic organisms in the ventilating systems of the London Underground and the Paris Metro designed to prove the feasibility of introducing bacteria and viruses for mass inhalation, thus producing a large scale civilian epidemic. Although this article produced a prompt and vehement denial from German quarters, it is believed possible that the Stead documents were genuine.' (f. 12)