Jap Herron was a novel written, supposedly, by a deceased Mark Twain from beyond the grave, dictated via the medium of a Ouija board. The scribe (faithfully taking down notes, or perhaps a little more than just that, depending on your view) was Emily Grant Hutchings, a woman who had actually corresponded with Twain 15 years earlier. In their exchange of letters he had given her advice and, interestingly, also marked one of her letters with the words: "Idiot! Must preserve". According to the lengthy introduction by Hutchings, "The Coming of Jap Herron", she and a woman named Lola Hays began receiving messages from Twain in 1915 when playing around with a Ouija board at a spiritualist meeting in St. Louis. Dallying with such occult techniques was not unusual for the time, and it seems receiving literary output from the great beyond was not so unusual either. The Jap Herron book came out at a time when the Ouija board communications of "Patience Worth" via St. Louis writer Pearl Curran, a friend of Hutchings (who was present during the first "communications" with Worth), was also capturing national attention. Indeed, as a New York Times article of the time remarks, Jap Herron was "the third novel in the last few months that has claimed the authorship of some dead and gone being who, unwilling to give up human activities, has appeared to find in the ouija board a material means of expression". This was, however, the most high profile author to be have been involved. Twain's daughter, Clara Clemens, took particular issue with the book, and she, along with the publishers Harper and Brothers, who for 17 years had owned the sole rights to Twain's works, went to court to halt the publication. In response, Hutchings and Hays, with the help of a certain Professor Hyslop, claimed that Clara's father (after more Ouija board activity) was "in a state of intellectual torture because of the difficulty he is having in getting his momentous work into print". The case, however, never went to trial as Hutchings eventually agreed to cease publication, and destroy any copies they could find, meaning surviving copies of the book are extremely rare.

Here is the aforementioned, subtly scathing, New York Times article on the book from 1917, the year it came out:

The ouija board seems to have come to stay as a competitor of the typewriter in the production of fiction. For this is the third novel in the last few months that has claimed the authorship of some dead and gone being who, unwilling to give up human activities, has appeared to find in the ouija board a material means of expression. This last story is unequivocal in its claim of origin. For those who are responsible for it appear to be convinced beyond doubt that no less a spirit than that of Mark Twain guided their hands as the story was spelled out on the board. Emily Grant Hutchings and Lola V. Hays are the sponsors of the tale. Mrs. Hays being the passive recipient whose hands upon the pointer were especially necessary. St. Louis is the scene of the exploit, as it is also of the literary labors of that ouija board that writes the "Patience Worth" stories. Emily Grant Hutchings, who writes the introductory account of how it all happened is from Hannibal, Mo., the home of Mark Twain's boyhood, and in her the alleged spirit of the author seems to have put much confidence. Her long description of how the story was written and of the many conversations they had with Mark Twain through the ouija board contains many quotations of his remarks that sometimes have a reminiscent flavor of the humorist's characteristic conversation.

The story itself, a long novelette, is scened in a Missouri town and tells how a lad born to poverty and shiftlessness, by the help of a fine-souled and high-minded man and woman, grew into a noble and useful manhood and helped to regenerate his town. There is evident a rather striking knowledge of the conditions of life and the peculiarities of character in a Missouri town, the dialect is true, and the picture has, in general, many features that will seem familiar to those who know their "Tom Sawyer" and "Huckleberry Finn." A country paper fills an important place in the tale, and there is constant proof of familiarity with the life and work of the editor of such a sheet. The humor impresses as a feeble attempt at imitation and, while there is now and then a strong sure touch of pathos or a swift and true revelation of human nature, the "sob stuff" that oozes through many of the scenes, and the overdrawn emotions are too much for credulity. If this is the best that "Mark Twain" can do by reaching across the barrier, the army of admirers that his works have won for him will all hope that he will hereafter respect that boundary.

Read Twain's own experience with the occult, from the living side this time, in his short piece about a seance he attended in 1866.