Second: Why does the four-dimensional vehicle present the exact appearance of the three-dimensional body--clothes and all? Third: How can it speak, _i.e._, set up vibrations in three-dimensional matter, as it is sometimes recorded as doing? It is admittedly far from easy to answer these questions, in the light of our present knowledge. As regards the first, I should feel disposed to say that such apparitions would be the rule rather than the exception, were it not for the fact that only those whose four-dimensional organs are fairly well developed can see them. Even so it may be that they are only called into activity as a result of some special "rapport" existing between the agent and the percipient. Professor Joire, in his book "Psychical and Supernormal Phenomena" points out that in nearly every case the percipient is in a state which he describes as "superficial somnambulism or passive mediumship" _i.e._, in some condition which from the facts of Hypnosis we may consider to be especially favourable to the receiving of supernormal impressions of any kind. This observation appears highly relevant and important. The second difficulty may be met, though not, I must admit, in a particularly convincing manner, by supposing that the four-dimensional vehicle is so mobile and plastic, in respect to appropriate forces, that it is capable of being moulded by the mere power of will. It would thus take the form which the agent commonly associated with himself, or which he observed his physical body to have after he had left it. It would be possible to adduce a number of considerations in support of this view, but none of them are in any way conclusive and I therefore leave the reader to form his own opinion on the matter. As regards the third point, there are two possible answers which might be offered. On the one hand it might be suggested that the words heard are really objective; the result, that is to say of actual vibrations in the atmosphere, and that this result is produced because, in all such cases, the percipient is sufficiently mediumistic to provide the necessary material for the agent to "work up" some form of speaking apparatus. This is very difficult to conceive as possible, and yet we must suppose some such process to be involved in the production of the "Direct Voice," a phenomenon which, though baffling, seems well authenticated. But this is rendered improbable by the cases where the speaking agent has been a living person, who records no such process as having taken place. Besides, it is grossly improbable that a living person, or for that matter a newly 'dead' person, would know how to perform this operation. The most probable explanation seems to be a combination of telepathic communication between the agent and the percipient accompanied by an auditory hallucination on the part of the latter. This would be, I think, quite natural.