'"Justified! How could that be?" I asked. I was astonished, as you may imagine, at the answer I had got. The doctor wheeled round his chair and looked steadily at me for a moment before he answered. '"I suppose you are not a man of science yourself? No; then it would be of no use my going into detail. I have always been firmly opposed myself to any partnership between physiology and psychology. I believe that both are bound to suffer. No one recognizes more decidedly than I do the impassable gulf, the fathomless abyss that separates the world of consciousness from the sphere of matter. We know that every change of consciousness is accompanied by a rearrangement of the molecules in the grey matter; and that is all. What the link between them is, or why they occur together, we do not know, and most authorities believe that we never can know. Yet, I will tell you that as I did my work, the knife in my hand, I felt convinced, in spite of all theories, that what lay before me was not the brain of a dead woman--not the brain of a human being at all. Of course I saw the face; but it was quite placid, devoid of all expression. It must have been a beautiful face, no doubt, but I can honestly say that I would not have looked in that face when there was life behind it for a thousand guineas, no, nor for twice that sum." '"My dear sir," I said, "you surprise me extremely. You say that it was not the brain of a human being. What was it then?" '"The brain of a devil." He spoke quite coolly, and never moved a muscle. "The brain of a devil," he repeated, "and I have no doubt that Black found some way of putting an end to it. I don't blame him if he did. Whatever Mrs. Black was, she was not fit to stay in this world. Will you have anything more? No? Good-night, good-night."