In 1943 concern still existed that the Germans might have prepared extensively for bacteriological warfare; had they, for example, already inoculated their troops against any specific virus?
In August 1943 George Merck, director of the War Research Service (the controlling body for bacteriological warfare in the United States) had proposed to the British experts at Porton that RAMC medics and American medical officers collaborate in sampling the blood of German prisoners of war.
Dr Paul Fildes, the head of the Biology Section, Experimental Station, Porton, near Salisbury, who was almost entirely responsible for the work, replied on September 8 that he thought nothing useful would come of such an investigation.
On May 21, 1944 Churchill wrote to Ismay reminding him that great progress had been made in bacteriological warfare, and Britain had ordered half a million bombs from American for use should this mode of warfare be employed by the Germans.
'I think we should be in a position to make and fill these bombs here,' he suggested, but was concerned that putting this before the chiefs of staff would widen the circle of those in the know.
On April 21, 1944 Fildes submitted a report on the operational tests with the four-pound 'N' bomb. These trials had produced in part catastrophic results - 'Even in our operations with N,' he would report some months later, 'we did not succeed in keeping our agents within bounds and have created conditions which will require consideration after the war.'
The bomb would be scattered in clusters over a two hundred yard square patch releasing their toxin as an odourless aerosol cloud which would cause death by inhalation of half the human beings up to a mile downwind from it, or up to two miles if they were running (the risk increasing with exertion).
Taking the city of Stuttgart as an example, the scientist assessed that a BW raid would need nearly two thousand clustered projectiles (each one being a five hundred pound container of the four-pound anthrax bombs); these could be carried by 83 Stirlings, 142 Lancasters, or 166 American B-17s and B-24s, and ideally be released simultaneously at the end of a conventional HE attack.
'An operation of this short,' promised Fildes, 'should kill a considerable number of people, either rapidly by inhalation or ore slowly by skin infection.'
In June 1944, the War Cabinet appointed an inter-Service sub-committee on Biological Warfare. They learned that no definite order had yet been placed in the United States for the manufacture of 'N' bombs; further trials were still being conducted on these frightful weapons. Churchill had however authorised top priority for all counter-measures to BW, and possible collaboration with SOE on BW operations.
Fildes now (July 21) reported again on BW. On August 14, he re-evaluated the half-million bomb order, and decided that the saturation figures needed revising.
At that time (January 6, 1944) they had believed that ten clusters would saturate one square mile, and that the six cities selected - Aachen, Wilhelmshaven, Stuttgart, Frankfurt, Hamburg and Berlin - would have 538 square miles of built up territories. This would require 570,280 anthrax bombs.
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