A group of Italian scientists set out to study the black stains that had been appearing on Leonardo da Vinci’s Codex Atlanticus—one of the world’s most valuable manuscripts. The Codex is a collection of 1,119 pages of notes and drawings by the Renaissance artist, and it is housed in the Biblioteca Ambrosiana in Milan.
The scientists used a form of microscopy called ultraviolet-visible spectroscopy, and they found that the black stains were made of carbon black—a type of pigment that was commonly used in Renaissance painting. But the source of the carbon black was a mystery.
The most likely explanation is that the carbon black came from soot that was produced by the candles that were used to light the room where Leonardo worked. In the 16th century, candles were made of tallow, which is a type of animal fat. When tallow candles are burned, they produce soot.
The scientists believe that the soot from the candles settled on the Codex Atlanticus over time, and that the black stains are the result of that process.
This is an interesting discovery because it provides a glimpse into the working habits of one of history’s greatest artists. Leonardo was known for his love of experimentation, and it seems that he was willing to try new things even when it came to lighting his workspace.