There is no recipe for the Ancient Tome. It must be obtained as a drop.
The Ancient Tome is a glowing book that’s dropped by raiders (barbarians, pirates, vikings, egyptian raiders, etc) during raids. The Ancient Tome cannot be crafted and is only available as a drop.
Using the Ancient Tome
There are two uses for the Ancient Tome, one use for the player and one for the Enchanter. The player’s use is that if you have the Ancient Tome in your inventory, it will glow when there is going to be a raid that night. The Enchanter’s use is to use the experience they collect from other workers to turn the Ancient Tome into a Book of Enchantment. When they do this, it will use up the Ancient Tome.