The Mathematics of Sewers.

Photo: Siologen

From the Bldgblog, a story about the mathematics of sewers:

Rumor has it that a university outside Manchester teaches courses in mathematics and knot theory not inside comfortable, well-lit classrooms – the university has none – but down in the sewers, drains, valves, and storm tunnels built long ago beneath the city. That subterranean world of old Victorian brickwork is measured, sketched, and catalogued every year by new students; they spend whole weeks at a time mapping the curvature of spillway walls, graphing intersections of unexplored side-channels.
The results are then compared to diagrams of Euclidean geometry.

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