In embalming, the mortician dunks a corpse in a casket-size vat of pungent chemical preservatives, usually glycerol and potassium acetate, then immediately wraps it in a shroud. Before the popularization of embalming, corpses were usually placed on ice to keep them fresh for funerals. (Embalming differs from embalment, in which a corpse is stripped of its innards and dehydrated.) Embalming preserves stunningly well. For instance, in the 1970s, archaeologists discovered the embalmed corpse of a Chinese noblewoman, who had died in 167 B.C., with her flesh moist, her hair firmly in her scalp, and her joints lithe.

As far as archaeologists and anthropologists can tell, embalming began with the ancient Egyptians in about 3200 B.C. Other cultures simultaneously developed methods for cleansing the dead, but few focused as intently on preserving their corpses. The tradition gained popularity in the United States, where Catholics and Protestants have ritualized the display of the corpse for extended periods of time. Embalming reached new levels of sophistication in the Soviet Union: Lenin's corpse has been on display in a Moscow mausoleum for almost 75 years. But every 18 months, technicians unbind the rubber bandages on the corpse and bathe it in chemicals. Every two weeks, they massage fluids into its exposed hands and head.