Archaeologists excavating parts of the ancient city of Pompeii made public new discoveries on Friday that provide a grim glimpse into the bleak existence of enslaved people two millenniums ago, including the existence of a “bakery-prison.”

The newly excavated area consists of a cramped space where donkeys and enslaved people lived, slept and worked together, milling flour to make bread. The single window that was found there provided dim light: it opened not to the outside world but to another room in the house, and was crossed with iron bars.

The brutality of the working conditions in the mills of the time is graphically described in Book XI of “The Golden Ass” by the second-century author Apuleius, the archaeological site noted in a statement issued Friday.

With their feet chained, and dressed in rags, Apuleius describes the workers as having “eyes so bleary from the scorching heat of that smoke-filled darkness they could barely see, and like wrestlers sprinkled with dust before a fight, they were coarsely whitened with floury ash.”

The donkeys were no better off: “Their flanks were cut to the bone from relentless whipping, their hoofs distorted to strange dimensions from the repetitive circling, and their whole hide blotched by mange and hollowed by starvation.”

Buried by an eruption of Mount Vesuvius in 79 A.D. under tons of lapilli, ash and rock, which would help to preserve it, Pompeii has over the centuries become a powerful symbol of the transience of life, and human impotence, when nature unleashes its power.