Walk down the middle of Broad Street in Oxford, taking care to avoid being hit by a car or, more likely, a bicycle, and you will see a cross of granite setts, exposed like an ulcer in the smooth tarmac of the road.
The Saxon princess-abbess-saint Frideswide was not the founder of Oxford: there was certainly a settlement at the confluence of the Cherwell and the Thames well before her time. But she has a claim to be one of the founders of the idea of Oxford, the notion of the city as a nexus of learning, religion, and occasional miracles.
Among the objects gathered in the collection of the Museum of the History of Science in Oxford are a number of devices coated with the patina of past celebrity. You can find Elizabeth I’s astrolabe, Lewis Carroll’s photographic developing kit, and a blackboard, chalk-inscribed equations intact, used by Albert Einstein.