I was sitting in my chair by the fireplace and polishing my boots up to a fine shine after a busy day tramping through the dusty streets of London, when first I heard it: a strange, muffled noise. A tish-tish-tish of a sound, which prolonged for some few seconds and then ceased abruptly. The noise appeared to emanate from either Holmes's bedroom or the bathroom beyond that. I cocked my head as a spaniel might and strained my ears, for it sounded like nothing I had heard before in our home. I could discern nothing further however, and so returned with a shrug to my boot buffing.

Then, the following evening, as I stood at the window looking down upon the street below and enjoying the cool twilight shadows resting against the streetlamps, I heard the sound once more. Tish-tish-tish. On this occasion it continued for perhaps a minute. I crossed the room quietly and pressed an ear to Holmes's door - a fraction too late, for the sound had stopped.

Scarcely had I moved away, than an instant later the door opened and Holmes emerged into the sitting-room.

"The night is drawing in, Watson," said he, "best to draw the curtains now, perhaps."

"Yes, Holmes, of course. By the way, old fellow, might you tell me what was that odd little noise coming out of your room not a moment ago?"

Holmes looked at me strangely. "An odd little noise?"

"Yes - a metallic clinking."

Holmes hesitated. "I cannot think what you mean," he said, finally. "I was in my room, brushing down a day suit, but my clothes brush does not produce any such metallic clinking. Unless, perhaps, you heard me emptying my pockets of loose change."

"I do not think that I did, Holmes," said I. "But never mind, it is hardly important."

And our talk turned to other matters.

One week later, I returned home from my club a little earlier than expected and entered the sitting-room to find it quite empty. I set about making myself comfortable for the evening when I froze in a half-stoop, for there was that same noise, once more, coming from the direction of Holmes's room. Tish-tish-tish. I walked up and tapped smartly.

"Holmes, are you in there?"

A silence. Then the door opened a crack and my friend's beaky nose popped out. An eye blinked at me. "Yes, Watson, I am here. You are back sooner than anticipated. Did you enjoy your evening?"

"It was very pleasant, thank you. There was that noise again, Holmes - that metallic clinking - directly in your room, I am quite sure of it. Is everything all right in there?" I smiled at my friend.

"Yes, Watson," Holmes replied, producing a hand that fluttered at me to cease and desist. "Now please, do stop worrying about clinkings, clankings, or anything else currently whirring around as a lost cause inside that brain of yours. Whatever you are hearing - why, it is surely the plumbing, or a loose window fitting, or a wardrobe door not quite catching; that is all."

And the door shut against me. From within I heard a busy movement, then the closing of a wooden drawer or lid, and the soft sound of a key turning in a lock.

The following morning, Holmes left early for a meeting with Inspector Lestrade at a property on the Great Monkton Road. I was left to my own devices therefore for an hour or two. I found that my curiosity was so piqued I could not resist the gnawing temptation to pop my head around the corner of Holmes's room, for he did not usually lock it unless we were both away on business. I had seen the interior of the room on only a very few previous occasions. It was quite small, and sparsely furnished with the bare essentials: a bed, a wardrobe, a cabinet and dressing table, a chest of drawers, a trunk. Papers and books were scattered across every surface, along with empty test tubes and various bottles and jars; there was nothing however which I could immediately spot that was made of metal or might produce an accidental clanging sound. I took a step inside the room, well aware that I was trespassing upon my friend's privacy, but vowing not to disturb any object within. The only article with a lock upon it was the wooden trunk set against the furthermost wall of the room. It was not a particularly large trunk; designed more for the storage of small valuables or mementoes than weighty treasures. It boasted an elegant engraving of a line of elephants, each holding the tail of the animal in front, on the lid. The wood was smooth and well polished. There was a small lip at the front, under which one's fingers could slide and pull on the unlocked lid to open it. As curious as I was, I did not test the lock. I stepped back from the trunk and returned to the sitting-room, where I sat myself down in an armchair and picked up the morning paper to divert my attention as best I could.

Two hours later and my friend had still not yet returned from his rendezvous with Lestrade. I stood and paced; I smoked a cigarette; I ate one of Mrs. Hudson's delicious jam scones; I spent a further minute picking the crumbs out of my moustache. Finally, after debating my quandary, I entered Holmes's room once more and plucked tentatively at the lid of the wooden trunk. Locked. With a tiny tsk of disappointment I backed out of the room and shut the door. As Holmes had said: it was likely a loose hinge somewhere, or a window fastening rattling in the breeze, and most certainly not anything which I had business occupying myself quite so entirely over. I was unable to explain why I had developed a morbid fascination in determining the origin of the odd little sound.

Holmes returned some thirty minutes later and adjourned briefly to his room to put on his dressing gown. I hovered by the door. I could hear only scrapings and footsteps. And then - was that a clink? I bent down and put my eye to the keyhole. It was most terribly unfortunate, then, that it was at that precise moment my friend chose to fling wide the door of his room.

"Watson!" said he, "What on earth do you think you are doing down there? Hunting for caterpillars?"

"Holmes!" said I, springing guiltily upright, "I am most terribly sorry! I did not mean for you to see me."

"That is quite evident, otherwise you would surely have knocked and entered as any polite person might, rather than creeping around as a furtive broke back. Would you care to explain your singular behaviour?"

I felt my cheeks flush scarlet. "I was listening for the tishing sound, Holmes."

Holmes's eyebrows shot almost up to his hairline. "With your eye to the keyhole?"

"Well, yes and no, Holmes. I was looking through the keyhole on the chance that I might actually see the object in question."

"Is a man's privacy worth nothing these days! Watson, please do not tell me that I must block my keyhole up with paper in the future, because that would really be very irksome."

"I beg your humble pardon, Holmes," said I. "I only wished to discover the source of the tish."

Holmes sighed. "Come in, then, and I shall show you the tish." He beckoned. "You will never give up, otherwise, will you, my boy? Come now, enter, you have my permission."

I stepped hesitantly into the room. Holmes moved across to the wooden elephant trunk and, taking a small key from his pocket, unlocked it. He placed his fingers under the lid and pulled it up and open. I was still standing close by the door and so could not immediately see what was inside. Holmes looked back at me with a half-smile upon his face. He foraged for a moment, then brought out a fuzzy brown bundle.

It was a clockwork monkey, holding a pair of cymbals between its furry paws.

"It is a monkey!" I said, utterly astounded.

"Yes," replied Holmes, observing me closely. "His name is Lestrade."

"He is very… ugly, Holmes," I said, in some bafflement.

"That is why I named him Lestrade," said my friend. He delved again into the trunk and pulled out another, similar, monkey. This one was rotund; his furry belly all but burst out of the seams of his hand-stitched waistcoat.

"This one is called Mycroft," said Holmes.

I started to laugh. Holmes turned the key on his back and Mycroft banged his cymbals together in merry greeting.

"Why do you have a collection of clockwork monkeys, Holmes?" I asked.

Holmes shrugged. "Why should I not? You would imagine me a severe sort of fellow with very obvious quirks and oddities, and this new eccentricity somehow surprises you? As some people collect butterflies, and others collect postage stamps, I collect… these charming creatures." He pulled out a third. It wore a mob cap and a white apron.

"Don't tell me, Holmes - this one is Mrs. Hudson?"

"Correct! Her insides are a little rusty and her cymbals are slightly bent, but she works all the same." And Holmes demonstrated by giving her key a couple of twists. Tish, tish, tish.

"There is yet one more in the trunk," said I, and I stepped forward to pick it up. I held it up to the light and admired it. He was a handsome chap with a wide, bonny smile, wearing a dark blue jacket embroidered with gold thread and decorated with tassels, and a red fez upon his bonny head.

"What is the name of this one, Holmes?" I asked my friend. "I think he is my favourite."

Holmes smiled softly. "He is mine also, Watson," said he. "He is the one that I treasure the most, and the one that gives me the most pleasure, for no matter how I treat him, if I should happen to drop him, or wind his key too far, he never complains; he will only ever smile at me in that sweet-natured way of his, and bang his cymbals without question." And Holmes took the toy gently from my hands and replaced him carefully inside the trunk once more.

Holmes never did tell me the name of the blue-jacketed monkey, and I confess that I quite forgot to ask him again.