Enlarge / An artist’s conception of Ptolemy using an instrument to observe the night sky. (credit: Getty Images)

It was only natural for Alexander Jones to feel thrilled when he saw a sixth century palimpsest at the Ambrosiana library in Milan for the first time. It happened in 1984 when Jones was working on his dissertation using manuscripts in Italy. With the tools at his disposal, including a portable ultraviolet lamp and microfilm, he could only read a few lines. But Jones’ interest was piqued because there were pages of the text that no one had succeeded in reading.

Those pages remained unread until this year when a large part of the text was deciphered by Jones, a professor of History of the Exact Sciences in Antiquity at New York University, who worked with Victor Gysembergh and Emanuel Zingg of the Paris-based Léon Robin Centre. The material they discovered appears to be a copy of Claudius Ptolemy’s treatise on a scientific instrument called the meteoroscope.

Finding Ptolemy

Ptolemy, who was born in 100 CE, was a renowned astronomer and mathematician who authored several important works, including Almagest and Geography. The treatise on the meteoroscope is a description of how to use the instrument for observations, as well as for doing astronomy calculations.