The first mistake was understandable.

The men tunneling through Herculaneum in 1752 were looking at black cylinders dug out of a villa buried beneath volcanic debris. They did not look much like books. The Biblioteca Nazionale di Napoli records that some were initially mistaken for pieces of charcoal and thrown away.

The error is a useful way into the story because almost everything about these books works backward from what we expect. Vesuvius damaged them and helped preserve them. Methods invented to read them destroyed some of what they revealed. Eighteenth-century drawings occasionally preserve letters that have since vanished from the originals. And now, nearly two thousand years after the eruption, the most promising way to open the books is to leave them physically closed.

The room underground

The Villa of the Papyri was enormous. Bourbon excavators reached it through tunnels because the building lay too deeply buried to expose conventionally. Roughly 1,800 papyrus fragments were recovered, probably representing around 800 original books. The collection is the only substantial library to survive from the classical Greco-Roman world.

The villa is often associated with Lucius Calpurnius Piso Caesoninus, Julius Caesar’s father-in-law and a patron of the Epicurean philosopher Philodemus. That remains an attribution rather than a nameplate recovered from the building. The distinction is worth keeping because the library has acquired enough mythology without our adding certainty where the archaeology does not provide it.

Heat from the AD 79 eruption carbonized the papyrus. Burial then isolated much of it from the ordinary cycles of oxygen, moisture and biological decay. The books survived as brittle carbonized objects.

Survived is a slightly generous word. A book nobody can open is only partly available to the living.

They cut them in half

The earliest attempts were destructive because the problem seemed insoluble in any other way. Camillo Paderni used a process later called scorzatura: a roll could be cut lengthwise, material removed from the center, and successive layers peeled away and copied. Reading the next layer could require sacrificing the one before it.

Other experiments were worse. The Naples library records scrolls treated with mercury, a papyrus whose writing disappeared after exposure beneath glass in sunlight, and an entire roll destroyed during an unsuccessful French unrolling attempt.

Piaggio’s machine

Antonio Piaggio arrived at Portici in 1753. He was a Piarist priest with experience handling ancient material and, more importantly, enough patience to build a machine around the fragility of the object rather than around the impatience of the reader.

Silk threads maintained tension while tiny sections were lifted and reinforced. It was painfully slow. That was the point. In 1754 Piaggio obtained an important success with PHerc. 1497, containing Book IV of Philodemus’ On Music. Modified versions of his method remained in use for generations.

Enough material emerged to establish that the villa contained works absent from the medieval manuscript tradition, including Epicurean philosophy by Epicurus, Philodemus and other writers. A smaller number of Latin works also survives.

The old facsimile drawings became historical objects in their own right. Naples notes that some preserve letters or portions of text that have since deteriorated on the originals. In a few cases, the copy is now the only witness to writing that the act of opening helped destroy.

The books that stayed shut

Hundreds of rolls remained unopened because physical access had reached the point where curiosity could become vandalism simply by succeeding. For a long time the choice was uncomfortable: preserve the book, or read it.

Imaging technology changed the terms. A high-resolution X-ray CT scan does not produce a hidden Greek page waiting to be opened in Photoshop. It produces a three-dimensional volume containing tightly compressed, warped, cracked and overlapping papyrus layers. Researchers must identify a surface, reconstruct it, flatten it digitally and then try to distinguish ink from carbonized papyrus.

That last step is ugly because both ink and papyrus are largely carbon-based. Machine-learning models can amplify subtle signals that may correspond to ink, but the 2026 research team is explicit that the models are not trained on letters, words, vocabulary or OCR targets. Papyrologists still have to read the Greek.

The inside of the scroll

The Vesuvius Challenge accelerated the work from 2023 onward. By early 2024, researchers had recovered more than 2,000 Greek characters from a still-rolled Herculaneum papyrus. In 2025, Oxford announced substantial internal images from PHerc. 172.

Then came PHerc. 1667. The surviving object is only a small fraction of the roll it once was and had already suffered from earlier attempts to open it. In June 2026, researchers announced that they had virtually reconstructed and read the surviving recoverable surface across roughly twenty columns. The accompanying technical preprint describes 22 column-equivalents over about 860 square centimeters.

That qualification needs to stay. “Complete” does not mean an intact ancient book has magically returned. The eruption damaged it. Later handling damaged it again. Virtual unwrapping cannot recover papyrus that no longer exists.

Nobody knows who wrote it

PHerc. 1667 has not supplied the convenient ending. Its author and title remain unknown. Handwriting and internal evidence suggest a date in the second century BC, perhaps earlier. The text concerns ethics, behavior, impulse and practical wisdom. Its vocabulary has invited discussion of Stoic philosophy and even Chrysippus, but the scholars have not attributed the work to him.

Another virtually recovered scroll, PHerc. 139, produced something more definite: enough of its closing title to identify Philodemus’ On Gods, Book 8. Until this work, only Book I of that treatise was known. One small title changed the known architecture of a philosophical work that had been fragmentary for two millennia.

The black object

Somewhere in the history of this collection, an excavator looked at one of these things and saw charcoal. I cannot really fault him. A carbonized Herculaneum roll does not look like the kind of object that contains an argument about virtue, music, gods or human behavior. It looks finished.

For more than two centuries, opening the scroll and damaging the scroll remained awkwardly close to the same operation. PHerc. 1667 is still physically what it was before the latest breakthrough: a small black roll, badly damaged, missing parts of the book it once contained.

Nobody had to peel away another layer to recover the new text.

Sources & Further Reading

The article relies primarily on the institutions that preserve, study and virtually reconstruct the Herculaneum papyri.

• Biblioteca Nazionale di Napoli, “Papirologia” — discovery history and destructive early opening methods.
• Biblioteca Nazionale di Napoli, “Officina dei Papiri Ercolanesi” — Piaggio’s workshop, drawings and collection history.
• The Herculaneum Society, “Papyri” — scholarly overview of the collection and preservation environment.
• “Complete virtual unwrapping and reading of a rolled Herculaneum papyrus” — 2026 technical preprint on PHerc. 1667.
• University of Kentucky, “The day the Herculaneum scrolls began speaking again” — institutional account of the 2026 PHerc. 1667 milestone.