Then I noticed that this man was leading my brother rather than walking arm-in-arm with him; he was a tall man, dressed in quite ordinary fashion. He wore a high bowler hat, and, in spite of the warmth of the day, a plain black overcoat, tightly buttoned, and I noticed his trousers, of a quiet black and gray stripe. The face was commonplace too, and indeed I cannot recall any special features, or any trick of expression; for though I looked at him as he came near, curiously enough his face made no impression on me, it was as though I had seen a well-made mask. They passed in front of me, and to my unutterable astonishment I heard my brother's voice speaking to me, though his lips did not move, nor his eyes look into mine. It was a voice I cannot describe, though I knew it, but the words came to my ears as if mingled with plashing water and the sound of a shallow brook flowing amidst stones. I heard, then, the words, 'I cannot stay,' and for a moment the heavens and the earth seemed to rush together with the sound of thunder, and I was thrust forth from the world into a black void without beginning and without end. For, as my brother passed me, I saw the hand that held him by the arm, and seemed to guide him, and in one moment of horror I realized that it was as a formless thing that has mouldered for many years in the grave. The flesh was peeled in strips from the bones, and hung apart dry and granulated, and the fingers that encircled my brother's arm were all unshapen, claw-like things, and one was but a stump from which the end had rotted off. When I recovered my senses I saw the two passing out by that gate. I paused for a moment, and then with a rush as of fire to my heart I knew that no horror could, stay me, but that I must follow my brother and save him, even though all hell rose up against me. I ran out and looked up the pavement, and saw the two figures walking amidst the crowd. I ran across the road, and saw them turn up that side street, and I reached the corner a moment later. In vain I looked to right and left, for neither my brother nor his strange guardian was in sight; two elderly men were coming down arm-in-arm, and a telegraph boy was walking lustily along whistling. I remained there a moment horror-struck, and then I bowed my head and returned to this seat, where you found me. Now, sir, do you wonder at my grief? Oh, tell me what has happened to my brother, or I feel I shall go mad."

Mr. Phillipps, who had listened with exemplary patience to this tale, hesitated a moment before he spoke.

"My dear madam," he said at length, "you have known how to engage me in your service, not only as a man, but as a student of science. As a fellow-creature I pity you most profoundly; you must have suffered extremely from what you saw, or rather from what you fancied you saw. For, as a scientific observer, it is my duty to tell you the plain truth, which, indeed, besides being true, must also console you. Allow me to ask you then to describe your brother."

"Certainly," said the lady, eagerly; "I can describe him accurately. My brother is a somewhat young-looking man; he is pale, has small black whiskers, and wears spectacles. He has rather a timid, almost a frightened expression, and looks about him nervously from side to side. Think, think! Surely you must have seen him. Perhaps you are an habitué of this engaging quarter; you may have met him on some previous Saturday. I may have been mistaken in supposing that he turned up that side street; he may have gone on, and you may have passed each other. Oh, tell me, sir, whether you have not seen him?"

"I am afraid I do not keep a very sharp lookout when I am walking," said Phillipps, who would have passed his mother unnoticed; "but I am sure your description is admirable. And now will you describe the person, who, you say, held your brother by the arm?"

"I cannot do so. I told you, his face seemed devoid of expression or salient feature. It was like a mask."

"Exactly; you cannot describe what you have never seen. I need hardly point out to you the conclusion to be drawn; you have been the victim of an hallucination. You expected to see your brother, you were alarmed because you did not see him, and unconsciously, no doubt, your brain went to work, and finally you saw a mere projection of your own morbid thoughts; a vision of your absent brother, and a mere confusion of terrors incorporated in a figure which you can't describe.