Newton's Apple Tree

Isaac Newton studied and later worked at Trinity College, and the story that a falling apple set him thinking about gravity dates to accounts he gave late in life, describing a tree at his family home, Woolsthorpe Manor in Lincolnshire, not anything in Cambridge itself. That original tree is thought to have died around 1815 to 1820, but not before cuttings and grafts had been taken from it and propagated onward as a genetically identical line. In 1954, Trinity College planted one of those grafts outside its main gate, directly below the room where Newton lived as a student. Being a 'Flower of Kent', an old English cooking apple variety, the tree produces fruit that is edible but unremarkable, tart and disease-prone rather than a variety anyone would choose for flavour alone. What makes it worth the stop is not the apples: it is standing in front of living plant tissue that traces back, graft by graft, to the actual tree behind one of science's most famous stories, fenced for protection but visible from the street outside Trinity's gate at any hour.