Crotch-high waders with tungsten-studded soles that will grip but won’t spark. A hard hat with a miner’s light. Heavy rubber gloves, oversized. A “turtle”—a curved metal box containing an emergency breathing apparatus—to strap around my waist, along with a backup battery. Finally, a safety harness that Happy helps me buckle with delicacy, as it loops through my legs near my groin. It’s tight but comfortable, and has the side benefit for male wearers of making all men seem rather well endowed. The harness will be the only means of dragging me out from the sewer into which I am about to descend, where the hazards include bacteria and viruses such as hepatitis A, B, and C; rabies and typhoid; and leptospirosis (“sewer workers’ disease”) that can be caught from rat urine, and in its severe form causes vomiting, jaundice, and death. There are also the gases. Methane, obviously. Hydrogen sulphide, known as sewer gas, which forms when organic matter decomposes in sewage, smells like rotten eggs and kills by asphyxiation.