As I turned the matter over in my mind, I half unconsciously scrutinized my visitor—­somewhat to his embarrassment—­and I liked his appearance as little as I liked his mission.  He kept his station near the door, where the light was dim—­for the illumination was concentrated on the table and the patient’s chair—­but I could see that he had a somewhat sly, unprepossessing face and a greasy, red moustache that seemed out of character with his rather perfunctory livery; though this was mere prejudice.  He wore a wig, too—­not that there was anything discreditable in that—­and the thumb-nail of the hand that held his hat bore disfiguring traces of some injury—­which, again, though unsightly, in no wise reflected on his moral character.  Lastly, he watched me keenly with a mixture of anxiety and sly complacency that I found distinctly unpleasant.  In a general way, he impressed me disagreeably.  I did not like the look of him at all; but nevertheless I decided to undertake the case.

“I suppose,” I answered, at length, “it is no affair of mine who the patient is or where he lives.  But how do you propose to manage the business?  Am I to be led to the house blindfolded, like the visitor to the bandit’s cave?”

The man grinned slightly and looked very decidedly relieved.

“No, sir,” he answered; “we ain’t going to blindfold you.  I’ve got a carriage outside.  I don’t think you’ll see much out of that.”

“Very well,” I rejoined, opening the door to let him out, “I’ll be with you in a minute.  I suppose you can’t give me any idea as to what is the matter with the patient?”

“No, sir, I can’t,” he replied; and he went out to see to the carriage.

I slipped into a bag an assortment of emergency drugs and a few diagnostic instruments, turned down the gas and passed out through the surgery.  The carriage was standing at the kerb, guarded by the coachman and watched with deep interest by the bottle-boy.  I viewed it with mingled curiosity and disfavour.  It was a kind of large brougham, such as is used by some commercial travellers, the usual glass windows being replaced by wooden shutters intended to conceal the piles of sample-boxes, and the doors capable of being locked from outside with a railway key.

As I emerged from the house, the coachman unlocked the door and held it open.

“How long will the journey take?” I asked, pausing with my foot on the step.

The coachman considered a moment or two and replied: 

“It took me, I should say, nigh upon half an hour to get here.”

This was pleasant hearing.  A half an hour each way and a half an hour at the patient’s house.  At that rate it would be half-past ten before I was home again, and then it was quite probable that I should find some other untimely messenger waiting on the doorstep.  With a muttered anathema on the unknown Mr. Graves and the unrestful life of a locum tenens, I stepped into the uninviting vehicle.  Instantly the coachman slammed the door and turned the key, leaving me in total darkness.