Dragons, Wyrms, and Wyverns: Their Unnatural History
Dragons, Wyrms, and Wyverns: Their Unnatural History, also known as Unnatural History, is an important corpus about dragons, wyrms, and wyverns, by Septon Barth, the Hand of the King of Jaehaerys I Targaryen. He was considered more of a sorcerer than a septon by his enemies. Because of this, copies of the book were burnt during the reign of Baelor I and it is hard to find. It claims that dragons are neither female nor male.
In the book Septon Barth also dispels the myth that a dragon can be slain by attacking down its gullet:
|“||Death comes out of a dragon's mouth, but death does not go in that way.||”|
A Dance with Dragons
While writing his dragonlore, Tyrion Lannister recalls that ten years ago he managed to get his hands on a fragment of Unnatural History by Septon Barth that had eluded the Blessed Baelor. He doubts any of Barth's work had found its way across the narrow sea.
While enslaved outside of Meereen Tyrion watches the Yunkish defensive preparations in the eventuality the black dragon should return. They are angling their scorpions and mangonels upward at the sky. Tyrion knows that they are wasting their time, and his thoughts turn to Barth’s words about the futility of attempting to slay a dragon via its gullet.