Algernon Blackwood 
Julius LeVallon: An Episode [EPUB ebook] 

A chance meeting between John Mason and Julius Le Vallon sparks a long-forgotten memory of a former life. Le Vallon reminds Mason of the Temple Days – a time hundreds of thousands of years ago when the two of them and a girl conducted a forbidden experiment which went disastrously wrong. The experiment unleashed the elemental powers of Wind and Fire, which Le Vallon has tried ever since to channel back to their domain. These attempts have always failed because the girl was not present. Now, as the story reaches its elemental climax millennia later, the three spirits are united and Le Vallon must face the ultimate challenge.