Demonism Verified and Analyzed: Now Available!
This work is an excellent look at some of the christian conceptions of demonology from its era, in the roaring twenties. Based on field work in China and India, mostly by the author but referencing other missionaries as well, it purports to prove that demons exist, that evil is the agency of Satan, and that mesmerism and psychology play a role in possession.
It contains several hundred of these anecdotes and speaks of strange idolatrous practices in typical early 20th century form, while listing polytheism and similar things as spiritually hazardous. Oddly, while proposing government moralism, it decries literal suppression of such beliefs in favor of mere coercion and education. It also attacks spiritualism.