“I had almost forgotten those things, for the war of the Rebellion broke out the next spring, and I was appointed surgeon in one of the new regiments, and was on my way to the seat of war.  But I had to pass through the city where the Professor lived, and there I met him.  My first question was about Rupert.  The Professor shook his head sadly.  ‘He’s not so well,’ he said; ’he has been declining since last Christmas, when you saw him.  A very strange case,’ he added, giving it a long Latin name,—­’a very singular case.  But go and see him yourself,’ he urged; ‘it may distract his mind and do him good?’

“I went accordingly to the Professor’s house, and found Rupert lying on a sofa, propped up with pillows.  Around him were scattered his books, and, what seemed in singular contrast, that drum I told you about was hanging on a nail, just above his head.  His face was thin and wasted; there was a red spot on either cheek, and his eyes were very bright and widely opened.  He was glad to see me, and when I told him where I was going, he asked a thousand questions about the war.  I thought I had thoroughly diverted his mind from its sick and languid fancies, when he suddenly grasped my hand and drew me toward him.

“‘Doctor,’ said he, in a low whisper, ’you won’t laugh at me if I tell you something?’

“‘No, certainly not,’ I said.

“‘You remember that drum?’ he said, pointing to the glittering toy that hung against the wall.  ’You know, too, how it came to me.  A few weeks after Christmas, I was lying half asleep here, and the drum was hanging on the wall, when suddenly I heard it beaten; at first, low and slowly, then faster and louder, until its rolling filled the house.  In the middle of the night, I heard it again.  I did not dare to tell anybody about it, but I have heard it every night ever since.’

“He paused and looked anxiously in my face.  ‘Sometimes,’ he continued, ’it is played softly, sometimes loudly, but always quickening to a long-roll, so loud and alarming that I have looked to see people coming into my room to ask what was the matter.  But I think, Doctor,—­I think,’ he repeated slowly, looking up with painful interest into my face, ’that no one hears it but myself.’

“I thought so, too, but I asked him if he had heard it at any other time.

“‘Once or twice in the daytime,’ he replied, ’when I have been reading or writing; then very loudly, as though it were angry, and tried in that way to attract my attention away from my books.’

“I looked into his face, and placed my hand upon his pulse.  His eyes were very bright, and his pulse a little flurried and quick.  I then tried to explain to him that he was very weak, and that his senses were very acute, as most weak people’s are; and how that when he read, or grew interested and excited, or when he was tired at night, the throbbing of a big artery made the beating sound he heard.  He listened to me with a sad smile of unbelief, but thanked me, and in a little while I went away.  But as I was going down stairs, I met the Professor.  I gave him my opinion of the case,—­well, no matter what it was.