I've been interested in Pompeii from an early age, ever since I first read about how the Roman town had been buried by an eruption of Vesuvius in 79 AD and that archaeologists were revealing it bit by bit just as it had been thousands of years ago. Images of the macabre body casts of the eruption's victims were terrifying and compelling to me at the same time. The 1972 film Pink Floyd at Pompeii made a perfect soundtrack to my early investigations, and the images of the band set up in the otherwise empty ampitheatre were haunting.

One of the most iconic products of the dig at Pompeii are the human body casts. Each one a three dimensional life size representation of the unfortunate people of Pompeii in their final moments. The pyroclastic surge that blanketed the town of some 20,000 souls came in a cloud of super heated, oxygen-depleted gas and eventually hardened around some of the victims. Not all those killed were preserved in this way, but as the bodies of those that were covered by volcanic ash decayed, "voids" were created in the shape of the original occupants. Since 1863, archaeologists have been creating "body casts" by pouring casting materials into these cavities so that as the ash is removed, the shapes of the victims would remain.

The story of the creation of the first body casts and the development of their status as works of art is presented at length in a wonderfully informative article in the journal Interpreting Ceramics. By 1863, excavation at Pompeii had been going on for almost 100 years and over 600 skeletons had already been exhumed in the normal manner of archaeological work. It wasn't until Giuseppe Fiorelli, then director of excavations, developed a process to capture the impressions on the inside of the voids by pouring them with a kind of plaster that the ghostly forms were revealed as we know them today.

The original casts were made with plaster, but plaster is not ideal for the purpose - introducing air bubbles, and actually shrinking after a time. An article in the New Scientist describes the technique used in 1984 to capture the shade of a girl using epoxy resin.

The Lady from Oplontis was fleeing from a villa near Pompeii, and died wearing her finest jewels and clutching a purseful of coins. The cast is made from more robust epoxy resin, and reveals her skeleton within and replicas of her jewellery in position.

Since the resin is transparent, the technique allows the victim's bones (where preserved) to be seen through the material as well as capturing impressive detail. A more perfect picture of a girl who lived almost 2000 years ago right at her most agonized moment of death. Suddenly the casts were no longer cartoonish, ghostly white, ethereal negative images, they had become surreal, clinical, ghastly, or even grotesque snapshots of someone's death.

The resin cast was a more complicated lost wax process, and only one cast of that type was authorized. In 1991 a newer process (a pressurized mixture of cement and resin) was used to reveal a family of seven. The new process is sufficient to show facial expressions. While much of Pompeii has already been excavated, archaeologists estimate that there are perhaps another 500 or so bodies preserved in the un-excavated sections. The newer techniques may reveal many even more horrible ghosts as the process is further refined, but in recent times there hasn't been much money to continue the work there.

The history of cast making is interesting, but the transformation of these grotesque and horrific ghost images of death into a venerated work of art is as well. The casts are given names like The Sleeping Man, The Watchdog (not all casts are of humans), or The Body of a Young Woman. Many of the most iconic casts were early attempts at the process which were made at a time when photography was still a new technology. Pictures of the bodies were printed around the world and apparently contributed to the subsequent popular acceptance of the "display of human remains in a scientific context" as the Ceramics article put it.

Where are the Images? Can anyone point me to a catalog of all Pompeii body casts? I'm surprised I couldn't find an image database online of all the finds!

Science is allowing us to discover more about Pompeii than we may have wanted to know, but if all you're interested in is a quick virtual tour of the architecture, check out Google's Street View of Pompeii. You can even walk around that ampitheatre.

Watch the PBS show Secrets of the Dead about neighboring Herculaneum.