Penicillin, Past, Present And Future -- Every stage of Penicillin's development is tested minutely. The Brown liquid, obtained from the flasks in which Penicillium mould has been grown, is checked for its activity. Laboratory workers dilute the liquid from the flasks, sterilize it, filter it through bacteria proof filters which gives a sterile solution. Fourteen years ago, Professor Fleming of the Chair, of Bacteriology at London University discovered that the mould Penicillium Notatum produced