Hill gave the world a modern postal system. His friends Priestley, Paine and Price helped inspire his radical educational ideas. He was persuaded by Bentham to move his school to London – de Quincey visited it. He joined Mill and Playfair in discussing economics, and declined Owen’s offer of involvement in living communally. An analysis of postal costs by Babbage (whose sons attended Hill’s school) probably informed his ideas, which Martineau supported tirelessly. He met Turner socially, visited Edgeworth in Ireland, knew Leigh Hunt, Roget, Airy, Lyell and Wheatstone, and found Trollope a challenging colleague.