The Florey Archives at London's Royal Society has a Florey letter (HF/1/3/2/1/19 )(previously 98HF.35.1.19) that didn't get shredded but probably was intended to be.
Dated December 4th 1941, it is addressed to Doctor "Cameron" at "Porton" and mentions scientists "Courtice" and "Gaddum".
Florey says ICI penicillin is at Porton and he is glad that Gaddum wants lots and lots of penicillin.
In December 1941, no one had much penicillin - certainly no patients in UK got any - and only Dawson's patients in the USA.
This must be some of the very first ICI penicillin ever produced - not for patients - but for 'Porton' .
One of Florey's very closest of his (very few) friends was Paul Fildes, very near the top of Britain's WWII Germ Warfare effort, which was centred at Porton Down.
That place has been for a century Britain's leading gas and germ warfare centre - in fact one of the top centres in the world for this highly secret activity.
Florey's first biographer, Bickel, indicated that in 1939, Florey had been asked by the War Office if he would be a consultant in 'poison gas research' (probably because of his proven skill in doing lethal experiments on small animals and his middle-aged chickenhawk attitude to the upcoming war.)
Florey had agreed.
I have always wonder if Florey's mystery month , mid July-mid August 1941, was somehow connected with him having informal talks on germ and gas warfare with various American researchers.
Certainly, Florey go top clearance for his trip to America from US and British officials - penicillin ,alone, seemed too unproven to warrant this kind of assistance.
Now Penicillin and Porton is like Jeckyll and Hyde to British audiences - no wonder this letter has never been mentioned in all the hagiography on penicillin and Florey.....
GR - Gordon Roy- Cameron *
FC -Frederick Colin- Courtice *
JH -John Henry- Gaddum
* Part of Florey's power was his cultivation of a network among the sizable Aussie contingent working in the UK - these two are but a tiny part of this group. Florey also cultivated ex pat britons who had taught in Australia.