Clock and Steam (2007)

From the introduction of the book:

Welcome to Clock and Steam, the sourcebook for clockwork and steam-powered technology for use in Dave Arneson’s Blackmoor. While the corebook for the setting mentioned some of the ways that these technologies have affected the world, this book fully illustrates just how much the world is changing because of it. The introduction of complex technology is not only a threat to arcane and divine spellcasters, but also helps to empower those without a natural aptitude for magic. As a result, new heroes and villains are on the rise - not because of arcane rituals, or the backing of powerful gods, but as a result of ingenuity and research. The solutions to many adventurers’ problems no longer lie solely within the province of the masters of esoteric lore; in recent times, students of scientific and technological advancement have come to the forefront, and are now making a name for themselves alongside their magically-inclined forebears.