Letter from Howard Walter Florey to J A H Giffard, 3rd Earl of Halsbury, National Research Development Corporation, Tilney Street, London Worthwhile investigating Cephalosporin P on man - not particularly toxic to animals - 250 gm would be sufficient for trials - cannot organise clinical tests but Medical Research Council might be able to do so - is enclosing reprints on isolation of Cephalosporin P - E P Abraham is not willing to act as development chemist for firm undertaking production - comments on this - advisable for firm undertaking production of Cephalosporin P to secure the cooperation of Mr Kelly at the MRC Antibiotics Research Station, Clevedon - says Clevedon people were able to send them a partially purified product. 28 May 1955