The history of medicine in Britain is full of the most bizarre cures for all manner of ailments, from the plague to the pox. A 16th century cure for dizziness was: "Take a young swallow from her nest when the crescent moon is in Virgo; cut off the head and let the blood run into a vessel containing frankincense; then give it to the patient when the moon is waning…" But amidst all the eccentric – and sometimes lethal! – treatments there were some that, incredibly, seemed to work; and they form the basis of many of the medicines we know today.