These few inquiries proved, however, to be a more lengthy proceeding than Holmes had imagined, for he did not return to the inn until nearly nine o’clock.  He was pale and dejected, stained with dust, and exhausted with hunger and fatigue.  A cold supper was ready upon the table, and when his needs were satisfied and his pipe alight he was ready to take that half comic and wholly philosophic view which was natural to him when his affairs were going awry.  The sound of carriage wheels caused him to rise and glance out of the window.  A brougham and pair of grays, under the glare of a gas-lamp, stood before the doctor’s door.

“It’s been out three hours,” said Holmes; “started at half-past six, and here it is back again.  That gives a radius of ten or twelve miles, and he does it once, or sometimes twice, a day.”

“No unusual thing for a doctor in practice.”

“But Armstrong is not really a doctor in practice.  He is a lecturer and a consultant, but he does not care for general practice, which distracts him from his literary work.  Why, then, does he make these long journeys, which must be exceedingly irksome to him, and who is it that he visits?”

“His coachman——­”

“My dear Watson, can you doubt that it was to him that I first applied?  I do not know whether it came from his own innate depravity or from the promptings of his master, but he was rude enough to set a dog at me.  Neither dog nor man liked the look of my stick, however, and the matter fell through.  Relations were strained after that, and further inquiries out of the question.  All that I have learned I got from a friendly native in the yard of our own inn.  It was he who told me of the doctor’s habits and of his daily journey.  At that instant, to give point to his words, the carriage came round to the door.”

“Could you not follow it?”

“Excellent, Watson!  You are scintillating this evening.  The idea did cross my mind.  There is, as you may have observed, a bicycle shop next to our inn.  Into this I rushed, engaged a bicycle, and was able to get started before the carriage was quite out of sight.  I rapidly overtook it, and then, keeping at a discreet distance of a hundred yards or so, I followed its lights until we were clear of the town.  We had got well out on the country road, when a somewhat mortifying incident occurred.  The carriage stopped, the doctor alighted, walked swiftly back to where I had also halted, and told me in an excellent sardonic fashion that he feared the road was narrow, and that he hoped his carriage did not impede the passage of my bicycle.  Nothing could have been more admirable than his way of putting it.  I at once rode past the carriage, and, keeping to the main road, I went on for a few miles, and then halted in a convenient place to see if the carriage passed.  There was no sign of it, however, and so it became evident that it had turned down one of several side roads which I had observed.  I rode