Letter from Howard Walter Florey to A H Cook Thought Cook was sending samples of his purified material [penicillin] - seems that Cook was testing Florey's ability to assay material - cannot waste time assaying random samples. On verso is a letter from Florey to John Ryan about penicillin supplies, 19 December 1942 - Florey regrets has no penicillin - had enquiry from Portugese Embassy about same matter - not likely to be of use in this case (endocarditis). 2 December 1942