This is not a novel, it is an attempt to turn the reader into a spiritualist

http://www.susanhatedliterature.net/2019/02/the-land-of-mist/ ( )

. . . in which the author defends the concept of spiritualism and attempts to convince the reader of the authenticity of mediums, ectoplasm, spirits and so forth. For those whose only acquaintance with Doyle has been the Sherlock Holmes mysteries, this short book provides a different perspective on the writer. ( )