Hollows in the ash
Visitors to Pompeii often remember the casts more than any building: figures curled on their sides, a person with hands over the face, a small child. These are not preserved bodies. They are plaster fillings of empty spaces that bodies once occupied. The method that produced them was devised in the 1860s by Giuseppe Fiorelli, an Italian archaeologist who directed the excavations after the unification of Italy.
To understand why it worked, it helps to recall how the town was buried. The eruption of 79 CE covered Pompeii first in pumice and ash, and the final surges laid fine, damp ash over everything. People who died were gradually surrounded by that fine material, which hardened around them. Over the following centuries the soft tissue and clothing decayed. The bones usually remained inside, but the ash around them kept the outline of the body as a cavity. Details of the phases are set out in the account of the Vesuvius eruption.
How Fiorelli’s method worked
Excavators had long noticed these hollows and sometimes found bones in them. In 1863 workers digging under Fiorelli’s direction encountered a cavity and he is reported to have had the idea of pouring liquid plaster into it. After the plaster had set, the surrounding ash was carefully removed. What emerged was a solid copy of the space, often including the folds of clothing and the form of a face or hand.
The process generally followed a few steps:
- Locating a void by probing or by noticing bones within the deposit.
- Making an opening, usually from above, and pouring in plaster mixed to a suitable consistency.
- Waiting for the plaster to harden, which could take some time.
- Removing the ash around it to reveal the cast, with the bones sometimes remaining embedded inside.
Fiorelli applied the technique to people and also to other organic things that had decayed, such as doors, furniture and plants. Later excavators used the same principle for tree roots and for animals, and it still informs how voids are treated today. Fiorelli is also known for dividing the town into numbered regions and insulae, and for pushing for more careful, systematic digging than his predecessors, a shift discussed in the history of the rediscovery of Pompeii.
What the casts show
Casts capture posture, not personality. Some figures appear to be covering their mouths with cloth, which suggests an attempt to filter the air. Others lie in positions that suggest sudden collapse. Their placement also tells researchers something about the timing of death: people found in the pumice layer died after the fall had begun, while those found within the later ash had remained in the town until the surges.
It is easy to read too much into the poses. Groups of casts found together are sometimes described as families, but such interpretations often rest only on proximity. Genetic work on remains from the site, an application of ancient DNA methods, has in some cases suggested that people who looked like relatives were not related. Scholars therefore treat popular captions with caution.
The poses are also affected by decay and by the way bodies were covered. The common impression of a person “frozen” at the instant of death should be handled carefully. The pose records the position in which the body came to rest, not a split second of suffering.
Restoration, loss and reconstruction
Casts made in the nineteenth century were sometimes repaired, and plaster was added to make them more complete or stable. Modern conservation work has examined them with CT scanning and X-rays, which can show the bones inside and the condition of teeth. Results have been used to estimate age, health and sometimes sex, though such estimates come with limits and have been revised by newer work.
Not every cavity yielded a good cast. Plaster could fill the void unevenly, and in some cases remains were disturbed during the process. The casts that visitors see therefore represent a selection of the most successful ones, not a full record of all the dead.
Ethical questions
The casts raise questions about how the dead are displayed. They are human remains, in the sense that the bones lie inside many of them, and they were made without any consent from the people involved or their descendants, who are long gone. Some archaeologists and museum professionals argue that putting them in public view risks turning a mass death into spectacle. Others hold that they are among the most effective ways to remind visitors that Pompeii was a town of real people.
The same debates occur around other collections of human remains, including the mummy scientific study carried out on Egyptian remains. Practical answers vary. Many sites choose to present casts with careful labelling, avoid dramatic lighting, and keep some in storage rather than on display. Where the site draws crowds, as Pompeii does, the choice is not simple, and reasonable people disagree.
What remains
Fiorelli’s casts transformed how the public imagines the city. They also helped establish that the site could yield information about the people, not just the buildings and paintings. Today the technique is used selectively, and researchers rely on other, less invasive methods when they can. The casts remain a powerful but incomplete record, and their meaning depends on the care taken in explaining them.