Mr. Davey has also produced raps and materialisations fraudulently. It is necessary to read, in Dr. Hodgson’s paper, the conditions under which he operated to see what ill-placed confidence his co-experimenters had in him (Davey). They do not verify, although they are invited to do so, the contents of a trunk precisely where the material essential to fraud was concealed; they allow Mr. Davey to close the door of the room: he gives two turns of the key, the one locking, the other unlocking the door, which is carelessly sealed with gummed paper; no one thinks of verifying if the door is well closed. The most elementary precautions are neglected by the assistants who, one would really think, had been chosen by Mr. Davey for their very credulity. Frauds as easy to prevent as those from which Dr. Hodgson draws his argument, cannot be considered as being able to take in a prudent, shrewd observer, accustomed to experimentation, and knowing how to preserve a little _sang-froid_. Was it not enough that the medium should have asked one of the observers: ‘What do you want the spirit to write on the slate? In what colour do you want the writing to appear?’ for these very questions alone to suggest imposture? Dr. Hodgson’s argumentation is inoperative, and the faults, accumulated by the deceived observers whose impressions he cites, are excessive. One would think he had had to do with very convinced spiritists, inclined to admit _a priori_ the reality of the forthcoming phenomena without troubling themselves about the precise conditions of their observations; this is what the perusal of the reports of these seances makes one think, for I read textually (p. 296): ‘It may be interesting to compare the reports given by spiritualists of a sitting with Mr. Davey with his account of what really occurred.’ Can one draw an argument from these accounts of spiritists? Some spiritists, convinced of the reality of the facts, appear to care very little indeed about any sort of control. To reason from their methods of observation, to generalise this reasoning and to extend it to all observers, is rather too easy a form of discussion.