Book Test(religion, spiritualism, and occult)
A book test is an experiment designed to ensure that telepathy is not the explanation of particular Spiritualist phenomena. The idea of book tests was started by Sir William Crookes, when he tried to devise a way of ensuring that a medium working with a planchette was not picking up any information through extrasensory perception. He asked the spirit if it could see the contents of the room and, on getting an affirmative answer, he reached back to the table behind him and picked up a copy of The Times that was lying there. Without looking, he placed a finger haphazardly on the open page. He then asked the spirit to give the word that was covered by his finger. In this instance the spirit spelled out “however.” Crookes found it to be the correct word. This result was published in the Quarterly Journal of Science for January, 1874.
In some book tests, the spirit communicates through the medium to give correct quotes from a book placed in a locked box, a book selected haphazardly by a bookseller and wrapped with others, and from a book sealed and given to a third party. Usually the book selected is one that the spirit knew and enjoyed when alive. The spirit is asked to give the passage from a particular randomly selected page and paragraph of the book, found on a particular shelf of a bookcase in the home of the sitter at the séance. Mediums through whom the spirits were particularly accurate included William Stainton Moses and William Eglinton.
One very striking example of a book test is given in Mysteries of the Unknown: Spirit Summonings (1989). The medium was Gladys Leonard and the sitter Lord Glenconner, whose son Edward—known to the family as “Bim”—had been killed in the battle of the Somme in 1916. The séance took place in December, 1917. The spirit of Bim directed his father to look at “the ninth book on the third shelf, counting from the left to the right, in the bookcase on the right of the door in the drawing room as you enter; take the title and look at page 37.” Lord Glenconner had a passion for forestry and a particular concern about wood-destroying beetles. This was such a strong passion that Bim and the rest of the family frequently joked about it. When he went to the designated book he found that it was titled Trees. On page 37 he found the sentence, “Sometimes you will see curious marks in the wood; these are caused by a tunneling beetle, very injurious to the trees.”