The Magic Engineer Saga of Recluce #3 L. E. Modesitt Jr. 1994
He is the Leonardo da Vinci of his age, but his insights violate the rules of the Order magic of Recluce, and in order to pursue his invention he must go into exile in the lands of Chaos.
Tortured by the knowledge that to preserve Order he must create new devices for war, Dorrin stands between Recluce and the forces of the Chaos that seek to destroy it.
