§ 23. Mr. Zilliacusasked the Secretary of State for the Home Department whether the civil defence exercises conducted on 11th May in Preston, Birmingham and Leeds, entitled Four Horsemen, on the theme that 50 hydrogen bombs had struck this country, were conducted with his authority; and what was the supposed explosive power, in megatons, of these putative bombs.
§ Mr. R. A. ButlerThis was an official exercise designed to test the system for handling reports of radio-active fall-out. Some 7,500 members of the Royal Observer Corps, 2,000 members of the Civil Defence Corps and nearly 400 members of the National Warning and Monitoring Organisation took part. In order to provide a full test for the system the bombs assumed to have been dropped varied in power from 20 kilotons to 13 megatons.
§ Mr. ZilliacusIs not it a fact that it is suggested by all the authorities which have pronounced themselves in this field that from six to a dozen 10-megaton bombs would obliterate all life in this island? Is not an exercise based on the assumption that 50 such bombs have fallen on this country fantastically unreal, and a piece of sinister make-believe?
§ Mr. ButlerNo, Sir. I am informed that the exercise was practical, and that in any case it provided a thorough test under the conditions which might arise.