Letter from Howard Walter Florey to N G Heatley, Peoria Says that penicillin yields are looking better - gives details of brewing process and results - substance has been purified a good deal further - American visit seems to have given English firms more interest - vague talk of firms combining resources - understands that Squibbs and Pfizer have some business arrangement - feels that any firm outside those pooling resources should contact the National Research Council Washington, about information - discusses experiments with steep liquor - would like to know how the commercial firms are doing. Added note: 4 November suggests that Heatley goes to Merck for a while - will be able to see Florey gets penicillin as soon as possible - discusses the oxidation of penicillin. 3 November 1941