Doctor Levillier grew more puzzled day by day.  His observation of Valentine taught him only one thing certainly, and beyond possibility of doubt and that was the death of the youth he had once loved, the living presence of a youth whom he could not love, whom he could only shrink from and even fear.  He held to the theory that this radical and ghastly change must be caused by some obscure dementia, some secret overturning of the mind; but he was obliged to confess to himself that he held to it only because, otherwise, he would be floating helpless, and without a spar, upon a tide of perplexity and confusion.  He could not honestly say that he was able to put his finger upon any definite signs of madness exhibited by Valentine, any that would satisfy a mad-doctor.  He could only say that Valentine’s character had been strangely beautiful and was now strangely evil, and that the soul of Julian was following rapidly the soul of Valentine.  The more closely he watched Valentine, the more astounded did he become and the more eager to detach Julian from him.  But the strangest thing of all, as the doctor allowed in one of his frequent self-communings, was, that though formerly he had loved Valentine better than Julian, it never occurred to him that the work of rescue might be undertaken on behalf of the former.  His mind dismissed the new Valentine into a region that was beyond his scope and power.  He felt instinctively that here was a soul, a will, that his soul could not turn from its ends or detach from its pursuits.  The new Valentine was a law to himself.  What moved the doctor to such horror was that the new Valentine was a law to Julian.  And there was something peculiarly dreadful in the idea which he held, that Julian, once under the beautiful influence of Valentine’s sanity, was now under the baneful influence of his insanity.  The doctor had gone the length of deciding, in his own mind, that Valentine’s sane period of life and insane period lay one on each side of a fixed gulf, and that fixed gulf was his long trance succeeding the final sitting of the two young men.  This conclusion was arrived at with ease, once the theory of a subtle lunacy was accepted as a fact.  For, on sending his mind back along the ways of recollection, the doctor was able to recall hints of the new Valentine dating from that very night, but never before it.  The first hint was Rip’s manifested fear, and this led on to others which have been already mentioned.  Having made up his mind that this trance was the motive power of Valentine’s supposed madness, the doctor sought in every direction to increase his knowledge on the subject of simulations of death by the human body.  He looked up again the cases of innumerable hysterical patients whom he had himself treated, sometimes with success, sometimes with failure.  He consulted other doctors, of course without mentioning the object of his research.  He endeavoured to apply to Valentine’s case standards by which he was quickly able to form