How can medicine that tastes like bubble gum make you feel better so quickly? It has penicillin in it--an antibiotic that helps treat bacterial infections. But we wouldn't have the drug without the work of Alexander Fleming. With historical images and details about key events before and after his discovery, this book will help kids understand the lifesaving impact of penicillin on the practice of medicine. Uncover the details of events that changed your world in this Pebble Explore series.