The Magic Engineer - The Saga of Recluce, Book 3

The saga of Recluce continues! In L. E. Modesitt's The Magic Engineer, we return to the magical island of Recluce, where Dorrin, a young scion of the Order magicians, is interested in forbidden knowledge, in the working of machines. Promising, intelligent, but determined to follow his passion for scientific knowledge, Dorrin can invent machines. He is the Leonardo da Vinci of his age, but his insights violate the rules of the Order magic of Recluce. Now he must go into exile in the lands of Chaos to pursue his dangerous inventions.
Yet Darrin remains loyal to the idea of Order, and is tortured by the knowledge that to preserve it he must constantly create new devices for war. For the forces of the Chaos wizards are moving across the land, devouring whole countries and creating an empire--and their ultimate goal is the destruction of Recluce