It has taken scholars over 500 years to decipher the meaning ‘locked’ within a 2,000-year-old papyrus from ancient Greece.

Covered in mirrored text, it has been located at the University of Basel’s library in Switzerland for hundreds of years, with the team of researchers continually hitting a wall.

However this month they finally announced a major breakthrough. Ultraviolet and infrared images of the papyrus unveiled that it was in fact made up of layers of plant fibre paper that had been glued together.

A manuscript specialist was then called in to assist the team, and managed to meticulously separate each individual page, making the Greek text legible for the first time.

“This is a sensational discovery,” said project leader and ancient history Professor Sabine Huebner.

“The majority of papyri are documents such as letters, contracts and receipts. This is a literary text, however, and they are vastly more valuable.”

After further research they discovered that it is a medical text from late antiquity, which describes “the phenomenon of ‘hysterical apnea'”.

“We therefore assume that it is either a text from the Roman physician Galen, or an unknown commentary on his work,” Professor Huebner said.

One of the most prominent figures in the history of medicine, Galen was a Greek physician who made a name for himself through his work on medicine and philosophy, and his notes and illustrations of the human anatomy.