“My first feeling, as I have just said, was one of pity and horror. My second, I fear, was rather one of professional satisfaction. I made notes of my patient’s pulse and temperature, tested the rigidity of his muscles, and examined his reflexes. There was nothing markedly abnormal in any of these conditions, which harmonized with my former experiences. I had obtained good results in such cases by the inhalation of nitrite of amyl, and the present seemed an admirable opportunity of testing its virtues. The bottle was downstairs in my laboratory, so, leaving my patient seated in his chair, I ran down to get it. There was some little delay in finding it - five minutes, let us say - and then I returned. Imagine my amazement to find the room empty and the patient gone.

“Of course, my first act was to run into the waiting-room. The son had gone also. The hall door had been closed, but not shut. My page who admits patients is a new boy and by no means quick. He waits downstairs and runs up to show patients out when I ring the consulting-room bell. He had heard nothing, and the affair remained a complete mystery. Mr. Blessington came in from his walk shortly afterwards, but I did not say anything to him upon the subject, for, to tell the truth, I have got in the way of late of holding as little communication with him as possible.

“Well, I never thought that I should see anything more of the Russian and his son, so you can imagine my amazement when, at the very same hour this evening, they both came marching into my consulting-room, just as they had done before.

“ ‘I feel that I owe you a great many apologies for my abrupt departure yesterday, Doctor,’ said my patient.

“ ‘I confess that I was very much surprised at it,’ said I.

“ ‘Well, the fact is,’ he remarked, ‘that when I recover from these attacks my mind is always very clouded as to all that has gone before. I woke up in a strange room, as it seemed to me, and made my way out into the street in a sort of dazed way when you were absent.’

“ ‘And I,’ said the son, ‘seeing my father pass the door of the waiting-room, naturally thought that the consultation had come to an end. It was not until we had reached home that I began to realize the true state of affairs.’

“ ‘Well,’ said I, laughing, ‘there is no harm done except that you puzzled me terribly; so if you, sir, would kindly step into the waiting-room I shall be happy to continue our consultation which was brought to so abrupt an ending.’

“For half an hour or so I discussed the old gentleman’s symptoms with him, and then, having prescribed for him, I saw him go off upon the arm of his son.

“I have told you that Mr. Blessington generally chose this hour of the day for his exercise. He came in shortly afterwards and passed upstairs. An instant later I heard him running down, and he burst into my consulting-room like a man who is mad with panic.

“ ‘Who has been in my room?’ he cried.

“ ‘No one,’ said I.

“ ‘It’s a lie!’ he resied. ‘Come up and look!’

“I passed over the grossness of his language, as he seemed half out of his mind with fear. When I went upstairs with him he pointed to several footprints upon the light carpet.

“ ‘Do you mean to say those are mine?’ he cried.