Letter from Howard Walter Florey to E Mellanby, Medical Research Council, London Is in contact with a firm which seems the most likely to turn out substantial quantities of penicillin - prepared to supply 200 gals of brew every 10 days, if Florey's lab will process it - can do this - no charge for brew but difficult to send - need milk-churns and petrol - can Mellanby help. 17 September 1942