Books like Le Livre des Médiums
Allan Kardec
Le Livre des Médiums is 459 pages, about 8 hours 25 minutes at 250 words a minute.
8 books to read next
How long each takes
Satan Is Alive and Well on Planet Earth 4.7 h 
The Ra Material 4.2 h 
The Occult Sciences 5.4 h 
Magick Without Tears 9.7 h 
Madame Blavatsky's Baboon 8.6 h 
The Unobstructed Universe 5.9 h 
Life and Teaching of the Masters of the Far East 4.7 h 
Occultism 1.5 h Bar height shows length. Estimated at 250 words a minute.