All day I turned these facts over in my mind, endeavouring to hit upon some theory which could reconcile them all, and to find that line of least resistance which my poor friend had declared to be the starting-point of every investigation. I confess that I made little progress. In the evening I strolled across the Park, and found myself about six o'clock at the Oxford Street end of Park Lane. A group of loafers upon the pavements, all staring up at a particular window, directed me to the house which I had come to see. A tall, thin man with coloured glasses, whom I strongly suspected of being a plain-clothes detective, was pointing out some theory of his own, while the others crowded round to listen to what he said. I got as near him as I could, but his observations seemed to me to be absurd, so I withdrew again in some disgust.
As I did so I struck against an elderly deformed man, who had been behind me, and I knocked down several books which he was carrying. I remember that as I picked them up I observed the title of one of them, "The Origin of Tree Worship," and it struck me that the fellow must be some poor bibliophile who, either as a trade or as a hobby, was a collector of obscure volumes. I endeavoured to apologise for the accident, but it was evident that these books which I had so unfortunately maltreated were very precious objects in the eyes of their owner. With a snarl of contempt he turned upon his heel, and I saw his curved back and white side-whiskers disappear among the throng.
My observations of No.427, Park Lane did little to clear up the problem in which I was interested. The house was separated from the street by a low wall and railing, the whole not more than five feet high. It was perfectly easy, therefore, for anyone to get into the garden, but the window was entirely inaccessible, since there was no water-pipe or anything which could help the most active man to climb it. More puzzled than ever I retraced my steps to Kensington. I had not been in my study five minutes when the maid entered to say that a person desired to see me. To my astonishment it was none other than my strange old book-collector, his sharp, wizened face peering out from a frame of white hair, and his precious volumes, a dozen of them at least, wedged under his right arm.
"You're surprised to see me, sir," said he, in a strange, croaking voice.
I acknowledged that I was.
"Well, I've a conscience, sir, and when I chanced to see you go into this house, as I came hobbling after you, I thought to myself, I'll just step in and see that kind gentleman, and tell him that if I was a bit gruff in my manner there was not any harm meant, and that I am much obliged to him for picking up my books."
"You make too much of a trifle," said I. "May I ask how you knew who I was?"
"Well, sir, if it isn't too great a liberty, I am a neighbour of yours, for you'll find my little bookshop at the corner of Church Street, and very happy to see you, I am sure. Maybe you collect yourself, sir; here's 'British Birds,' and 'Catullus,' and 'The Holy War'—a bargain every one of them. With five volumes you could just fill that gap on that second shelf. It looks untidy, does it not, sir?"
I moved my head to look at the cabinet behind me. When I turned again Sherlock Holmes was standing smiling at me across my study table.
I rose to my feet, stared at him for some seconds in utter amazement, and then it appears that I must have fainted for the first and the last time in my life. Certainly a grey mist swirled before my eyes, and when it cleared I found my collar-ends undone and the tingling after-taste of brandy upon my lips. Holmes was bending over my chair, his flask in his hand.
"My dear Watson," said the well-remembered voice, "I owe you a thousand apologies. I had no idea that you would be so affected."
I gripped him by the arm.
"Holmes!" I cried. "Is it really you? Can it indeed be that you are alive? Is it possible that you succeeded in climbing out of that awful abyss?"
"Wait a moment," said he. "Are you sure that you are really fit to discuss things? I have given you a serious shock by my unnecessarily dramatic reappearance."
"I am all right, but indeed, Holmes, I can hardly believe my eyes. Good heavens, to think that you—you of all men—should be standing in my study!" Again I gripped him by the sleeve and felt the thin, sinewy arm beneath it. "Well, you're not a spirit, anyhow," said I. "My dear chap, I am overjoyed to see you. Sit down and tell me how you came alive out of that dreadful chasm."
He sat opposite to me and lit a cigarette in his old nonchalant manner. He was dressed in the seedy frock-coat of the book merchant, but the rest of that individual lay in a pile of white hair and old books upon the table. Holmes looked even thinner and keener than of old, but there was a dead-white tinge in his aquiline face which told me that his life recently had not been a healthy one.
"I am glad to stretch myself, Watson," said he. "It is no joke when a tall man has to take a foot off his stature for several hours on end. Now, my dear fellow, in the matter of these explanations we have, if I may ask for your co-operation, a hard and dangerous night's work in front of us. Perhaps it would be better if I gave you an account of the whole situation when that work is finished."
"I am full of curiosity. I should much prefer to hear now."
"You'll come with me to-night?"
"When you like and where you like."
"This is indeed like the old days. We shall have time for a mouthful of dinner before we need go. Well, then, about that chasm. I had no serious difficulty in getting out of it, for the very simple reason that I never was in it."
"You never were in it?"
"No, Watson, I never was in it. My note to you was absolutely genuine. I had little doubt that I had come to the end of my career when I perceived the somewhat sinister figure of the late Professor Moriarty standing upon the narrow pathway which led to safety. I read an inexorable purpose in his grey eyes. I exchanged some remarks with him, therefore, and obtained his courteous permission to write the short note which you afterwards received. I left it with my cigarette-box and my stick and I walked along the pathway, Moriarty still at my heels. When I reached the end I stood at bay. He drew no weapon, but he rushed at me and threw his long arms around me. He knew that his own game was up, and was only anxious to revenge himself upon me. We tottered together upon the brink of the fall. I have some knowledge, however, of baritsu, or the Japanese system of wrestling, which has more than once been very useful to me. I slipped through his grip, and he with a horrible scream kicked madly for a few seconds and clawed the air with both his hands. But for all his efforts he could not get his balance, and over he went. With my face over the brink I saw him fall for a long way. Then he struck a rock, bounded off, and splashed into the water."
I listened with amazement to this explanation, which Holmes delivered between the puffs of his cigarette.
"But the tracks!" I cried. "I saw with my own eyes that two went down the