Dayton (The Eternal Rose
) never quite makes good on the engrossing buildup of this lengthy tale set in an alternate 19th-century Europe. The Imperial Council of Magicians forbids women to practice magic, so hapless servant Jax has spent 200 years searching for an heir to the last blood sorceress; at last he finds her in hedge witch Amanusa Whitcomb. Reluctant and afraid, Amanusa lets Jax teach her about blood magic. When she finally uses her powers, she and Jax flee from the Inquisitors, encountering disturbing “dead zones” devoid of life and magic. The burgeoning love between Amanusa and Jax is well-crafted and honest, but Dayton allows it to overwhelm the complex plot and world-building, leaving hundreds of pages of foundation crumbling without a suitable capstone. (Mar.)