Letter from Howard Walter Florey to James C Cain, Technical Divsion, National Research Development Corporation, Tilney Street, London In long run, should be useful for MRC Antibiotics Clinical Trials Committee to have 500 gm of Cephalosporin C - thought it would be better for them to wait until they have results of Oxforc experiments on the promised 100 gms - heard from Glaxo about difficulties of supply of carbon for Cephalosporin C - comments on this. 16 March 1956