Eu acredito que você está falando sobre Changeling , um 1980 Roger Zelazny romance. Existe uma sequência, Madwand .
In the world of magic, the young Mark Marakson is obsessed with devices, building water wheels and later, steam engines. He does not understand why the people on the farms and villages rely on magicians rather than using the machinery he creates. Young Pol, meanwhile, grows up a poet, musician and singer, marked by the white streak in his dark hair. He is a great disappointment to the man he regards as his father, who is an engineer. From time to time he sees glowing strands in the air which he can touch to make things happen.