No storm. No rocks. Just a calm September evening — and 650 people gone in four minutes. On 3 September 1878, the pleasure steamer Princess Alice was bringing hundreds of families home from a day at the Kent coast when she was struck on the Thames by a collier many times her size and cut almost in two. She sank in under four minutes. But the water itself was a second death: shortly before the collision, London’s sewers had discharged into the river, and the families went into a tide thick with the city’s filth. Around 650 died — so many that the true number was never known, because no one had counted the passengers. One man lost his wife and all seven of his children. The steamer company’s own manager lost his wife and four. An inquiry argued over which vessel had turned the wrong way. No one was punished. The company kept sailing, and the river kept taking London’s sewage. When hundreds of families drown in filth their own city poured into the water, is that an accident — or the p...