The ritual involves carefully removing the bark of a canticle tree with a traditional tool called a draw knife which in turn attracts the Ancestor Moth. Once enough moths are in the vicinity, they grant the reader with the second sight needed to decipher the scroll.
The voice of the Ancestor Moth has always been an integral part of reading an Elder Scroll. They maintain a connection to the ancient magic that allows a Moth Priest to decipher them. Moths within an Ancestor Glade emanate a soft harmonious trilling that when amplified tap into a form of primal augur. The allows the moths themselves to become a conduit for deciphering the scrolls. By having the moths close to the Moth Priest, they can utilize the conduit and share the moth's augury.
Every Moth Priest is taught this ritual, but only the most resilient can read the scrolls in this manner as it takes years of practice to interpret the harmony. As such, few ever get the chance to perform it.
- The Elder Scrolls V: Dawnguard (First appearance)